Dresser-Rand. Instruction Manual for Single Stage 350, 500, and 700 Frame Steam Turbines (2011)

SST Turbine Instruction Manual

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h. Complete installing flange bolts using the sequence in Figure L-3 and the

applied torques in Table L-2.

After the turbine is completely re-assembled and the coupling is made up, it

should be brought up to operating temperature and the bolts checked again.

There should be no slacking off of the bolts as a result of heating and cooling.

When removing or replacing the top half of the casing, great care must be

exercised to avoid damage.

L.4

Carbon Ring Removal and Replacement

L.4.1

Carbon Ring Removal

Refer to the following figures:

L-4

Carbon Ring Assembly, Non-Condensing Turbine

L-5

Carbon Ring Assembly, Condensing Turbine

Figure L-4 Carbon Ring Assembly, Non-Condensing Turbine

When removing the packing rings, be sure to keep each ring by itself. Note that the

ring segments are marked; these marks should be placed together when fitting or

replacing the rings in the turbine. When gland leakage indicates the necessity of

packing ring maintenance, it is recommended that new rings be installed.

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New packing rings furnished by Dresser-Rand will be made with the correct

diametral clearance, based on the original contract steam conditions. A packing

ring diagram, EW-33275 located in Appendix A, shows the part number and

location of each ring in the turbine.

When it is necessary to refit old rings (due to emergency condition) remove a small

amount, approximately

0.001”/0.025 mm from the ends of each segment,

maintaining flat square ends. The diametral clearance between the carbon rings

and the shaft should be as specified in the Packing Ring Diagram.

When installing new rings, the shaft surface should be smooth and highly polished,

clean and free of dust, water or oil. The spacer rings should be clean and smooth

with a true surface. If the sealing surface of the spacer ring is warped, the carbon

ring cannot seal. Warped spacer rings should be replaces. To install new carbon

rings, see Figure L-6 for procedure.

Figure L-5 Carbon Ring Assembly, Condensing Turbine

a. If there is a leak-off connected to the cover disconnect this and remove the

pipe from the cover.

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b. Remove turbine cover according to the procedure specified in Section L.3.1.

c. Disconnect the garter spring ends. Remove the garter springs and carbon ring

segments. Note that the anti-rotation pin in the packing case may interfere

with carbon ring segment removal. If so, simply rotate the segment in the

opposite direction, or rotate the partition plate.

d. Inspect and clean the spacer rings. If the spacer rings are damaged they should

be replaced. The shaft will have to be removed. Refer to Section L.9 Rotor

and Turbine Wheel Removal and Replacement.

e. Clean the stainless steel high velocity oxy fuel-coated surfaces of the shaft

with stainless steel high velocity oxy fuel spray. Inspect the stainless steel

plating. If plating is bubbled, split or peeling the shaft must be replaced.

L.4.2 Carbon Ring Replacement

a. Thread the garter springs into the slots between the spacer rings.

b. Install the carbon ring set one complete set at a time. Be certain to maintain

the correct relationship between carbon ring segments by matching dots

stamped on each segment. Dots should face toward the wheel. The anti-

rotation notch must engage the anti rotation pin.

c. Connect the garter springs to retain the carbon rings.

d. Replace the turbine cover per Section L.3.1.

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Figure L-6. Typical Carbon Packing Installation

L.5

Casing Labyrinth Seal Removal and Replacement

No field repairs of labyrinth are recommended. Slight deposits of the labyrinth on

the turbine shaft is an acceptable condition.

When installing new labyrinth rings, polish the shaft clean to remove any deposits

which may have formed.

Make sure that the quadrants of each ring are matched and that the rings are

installed in their proper position as identified in the packing ring diagram, EW-

33275. On installation of each quadrant of a gland-packing ring, make sure a

compression ring is installed in each hole. (See Figure L-7)

All SST turbine designs require removal of the turbine cover to remove, inspect,

and replace labyrinth seals. Refer to the appropriate section below to service these

labyrinth seals.

L.5.1

Casing Labyrinth Seal Removal

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Refer to the following figure:

L-7 Labyrinth Seal Assembly

a. Remove the turbine cover according to the procedure specified in Section

L.3.1. The labyrinth seal segment(s) in the cover will be removed during this

operation.

b. Remove leak-off piping before removal of seals.

c. Inspect labyrinth seal segments, locating springs, and the shaft for corrosion,

scoring, or other damage. Clean all components. Replace any part that is no

longer serviceable. Labyrinth seal segments must be replaced as a set. Severe

rubbing one side of all labyrinth teeth may indicate a worn or failed thrust

bearing. Refer to Section L.6.2, Thrust Bearing Removal and Replacement, if

the thrust bearing is suspect.

L.5.1

Casing Labyrinth Seal Replacement

a. Install labyrinth seal segments into the lower half casing by rotating them

between the shaft and casing. Install the locating springs in the depressions, in

the segment and compress the springs as the segment is rotated.

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b. Install the labyrinth seal segments into the seal housing lower half with

springs. Note that the labyrinth seal segments are matched-marked. Insure

that they are installed with their match-marks next to each other.

c. Install the labyrinth seal segments and springs in the seal housing upper half.

d. Replace the turbine cover and gland-housing cap according to the procedure

specified in Section L.3.1.

L.6

Turbine Bearing Removal and Replacement

SST turbines can be supplied with two, split sleeve journal bearings and one ball

thrust bearing. Shaft journal and bearing dimensions are shown on the turbine data

sheets. When running clearance is excessive, the bearings should be replaced not

re-babbitted. Approximately 0.004”/0.101mm over the maximum clearance is

considered excessive. However, if conditions permit and the unit runs smoothly,

bearings may be kept in service when clearances exceed the recommended

maximum clearance. It is left up to the discretion of the operating engineer as to

when bearing replacement is necessary. The bearings are longitudinally split to

permit removal and installation without removing the shaft.

Refer to the following figures:

M-4

Bearing Housing Assembly, Exhaust End Simple Bearing Case

M-5

Bearing Housing Assembly, Exhaust End Hi Cap Bearing Case

M-6

Bearing Housing Assembly, Non-Drive End Simple Bearing Case

M-7

Bearing Housing Assembly, Non-Drive End Hi Cap Bearing Case

L.6.1

Sleeve - Type Journal Bearing Removal and Replacement

The journal bearing can be inspected and replaced without removing the turbine

upper case.

Sleeve Bearing Removal

a. Remove the bolts securing the governor mounting housing to the steam end

bearing cap.

b. Use a soft drift and hammer to loosen the upper half of the bearing housing.

Tap on the area where the upper half overlaps the lower half. Remove the

upper half.

c. Lift, raise, and slide oil rings over to allow removal of the upper bearing half.

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d. Raise the shaft slightly (0.040 inch/1 mm) to expose the bearing split line and

remove the upper bearing half.

e. Rotate lower bearing half out of the bearing housing with the locating tab

exiting the housing upon initial rotation.

The shaft can then be rested on the labyrinth seal or optional Inpro/Seal after

the bearing is removed.

g. Inspect bearings for wear or scoring. Replace if necessary. Refer to Section

B.9 for recommended sealant.

h. Inspect shaft journals. If journals are worn or scored, the shaft must be

replaced. Slight scratches or nicks can be removed by stoning or with crocus

cloth.

Sleeve Bearing Replacement

Verify that the bearing journal is clean and undamaged. Coat the journal with

turbine oil.

Lift the shaft (0.040 inch/1 mm) to permit sufficient room to rotate the lower

bearing half into the housing.

Rotate lower bearing half into bearing housing with the locating tab correctly

aligned with the slot in the housing. Note that the bearing split line is below

the bearing housing split line. On installation, the bearing stops will act as

dowels and properly locate the bearings.

Lower the shaft onto the lower bearing half.

Snap the upper half of the bearing into the upper bearing housing half, aligning

the tab so that it fits into the milled slot. After installation, check clearance

using plasti-gage or lead wire.

Place the oil ring(s) into slot(s) on the upper bearing half and verify that they

are free to turn.

Drain and clean bearing housing reservoirs and refill to the proper level with

clean oil.

Apply a thin coating of sealant to the horizontal joint of the bearing housings.

Refer to Section B.9 for recommended sealant.

Replace the bearing cap carefully, so as not to crush the sleeve bearing tabs.

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Insert and drive in the dowel/taper pin.

k. Install washer and nuts on studs. Torque the nuts first to 25 ft-lbs (34 N-m)

and then to 55-65 ft-lbs (75-88 N-m).

Install bolts and torque them to 55-65 ft-lbs (75-88 N-m).

m. Rotate shaft by hand and observe oil rings through inspection holes in the

bearing cap to verify that rings rotate freely.

n. Install bolts holding upper bearing housing half to governor mounting housing.

L.6.2

Thrust Bearing Removal and Replacement

The standard thrust bearing is a ball bearing located in the non-drive end bearing

housing. Tilting pad thrust bearings are supplied optionally on some turbines.

Refer to the appropriate vendor manual for details.

For turbines where the governor is coupled to the shaft, remove steam end bearing

case cap and then uncouple and remove the governor. For gear driven Woodward

governors disconnect the governor linkage without disturbing the length of the

connecting rod, then remove the bolts that fasten the governor to the housing and

lift off the governor.

The thrust bearing is properly positioned on the turbine shaft by shims at the

factory and should require no adjustment. These shims are used to adjust the

nozzle ring-to-wheel clearance. See figure L-8. Shims are also used to set the

running clearance (float) on a shoe or collar type thrust bearing. Recommended

running clearance for the thrust bearing is 0.010” to 0.020”.

Thrust Bearing Removal

a. Remove the turbine rotor according to the procedure specified in Section L.9.

b. Remove lock nut and lock-washer from the turbine shaft.

c. On turbines with ball bearing journal bearings, remove the oil ring and oil

ring sleeve.

d. Using a suitable puller, remove the thrust bearing from the shaft. Tag both

sets of upper and lower shims to facilitate re-assembly.

e. Using a suitable puller, remove the journal ball bearings from the

shaft.

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CAUTION

When removing or replacing ball bearings mounted on a shaft,

NEVER PRESS OR APPLY FORCE to the OUTER RACE, as

this may damage the races or balls. NEVER HAMMER on

either the inner or outer races. Bearings should be pressed on

or off shafts with a steady force. Always inspect the shaft for

burrs or foreign material and remove them as necessary, prior

to removal or installation of bearings. If a BEARING BINDS

during installation or removal, DETERMINE THE CAUSE and

CORRECT it rather than apply more force. Installation should

be performed by heating bearings prior to assembly. Heat

bearings slowly and evenly to a temperature not exceeding

250F (120C). Special electrical heaters are available from

industrial suppliers for bearing heating. Alternatively, bearings

may be heated in an oil bath.

On turbines with sleeve journal bearings, take care not to lose the flat spring

located in the bottom of the bearing housing groove. This spring prevents

rotation of the outer race of the thrust bearing.

Thrust Bearing Replacement

a. Install thrust bearing on the shaft with the shield (if so equipped) facing out.

Make sure that the bearing is installed with the manufacturer’s marking, such as a

bearing number or “thrust here”, facing upstream (towards the steam end of the

shaft). Before installing the bearing case cap, check thrust bearing adjustments for

the proper thickness of shims: 0.050”, 1.27mm minimum with assembled shaft

moved fully towards steam end. Set the clearance by properly positioning the

thrust bearing. See Figure L-8 below:

Figure L-8 Nozzle Ring-To-Wheel Clearance

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On turbines with ball bearing journal bearings, replace the oil ring sleeve and

the oil ring.

Replace lock-washer and lock nut.

Bend the lock tab(s) to lock the nut into position.

Replace the turbine rotor into the turbine casing according to the procedure

specified in Section L.9.

To replace a ball-type thrust bearing, see steam end bearing case assembly and

longitudinal section drawings in Appendix A and proceed as follows:

Remove governor.

Remove steam end bearing case cap.

Remove bearing case end cover.

Disassemble parts from steam end of turbine shaft as necessary to gain access

to the thrust bearing; then remove the bearing. Tag both sets of upper and

lower shims to facilitate reassembly.

Reassemble by reversing the removal procedure. Make sure that the bearing is

installed with the manufacturer’s marking, such as bearing number or “thrust

here”, facing upstream (towards the steam end of the shaft). Before installing

the bearing case cap, check the thrust bearing adjustments for the proper

thickness of shims.

L.6.3

Ball-Type Journal Bearing Removal and Replacement

Bearing removal and replacement on SST 500 and SST 700 turbines with ball

bearing journal bearings is accomplished using the same procedure as that specified

for the thrust bearing in section L.6.2, Thrust Bearing Removal and Replacement.

The only exception is that there is no lock washer or nut retaining the bearing on

the drive end of the shaft. Removal of the exhaust end bearing requires the

removal of the coupling and outboard bearing housing seal. Refer to Section L.5,

Casing Labyrinth Seal Removal and Replacement.

L.7

Bearing Housing Shaft Seal Removal and Replacement

Bearing housings are provided with either labyrinth-type oil seals or optional inpro

seals or magnetic seals. These seals prevent oil leakage from bearing housings and

also prevent penetration of steam, dust, and dirt into the housings.

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Bearing housing shaft seals are mounted on the turbine shaft. There are two seals

on the drive end bearing housing and one on the non-drive end bearing housing.

Inpro seals & magnetic seals are optional, non-contacting bearing housing oil seals

that replace the three standard labyrinth-type bearing housing seals. The drive end

bearing housing has both an inboard and outboard seal. The non-drive end has only

an inboard seal.

Inpro or Magnetic Seal Removal (Steam End)

Refer to the following figure:

L-9

Bearing Housings With Optional Inpro/Seals

a. Remove the half-coupling from the shaft.

b. Remove the rotor from the turbine according to the procedure specified in

Section L.9.

c. On sleeve bearing turbines, remove the thrust bearing from the shaft according

to the procedure specified in Section L.6.2

d. Clean the turbine shaft outboard of the seal.

e. Slide the seal assembly off the turbine shaft.

Inpro or Magnetic Seal Replacement (Steam End)

a. Clean the shaft and remove any burrs that could damage the seal O-ring.

b. Lubricate the shaft and seal O-ring with turbine oil to facilitate seal insertion

on the shaft.

c. Slide the seal assembly onto the shaft, placing it at is approximate final

position.

d. On sleeve bearing turbines, replace the thrust bearing according to the

procedure specified in Section L.6.2

e. Replace the rotor according to the procedure specified in Section L.9, using

care to correctly position the seal when installing upper halves of the bearing

housings.

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Replace half-coupling on the shaft.

Inpro or Magnetic Seal Removal (Exhaust End)

(Note: Rotor must be out of the turbine.)

a. Remove the half-coupling from the turbine shaft.

b. Remove journal bearing, oil slingers, and any other items located outboard of

the innermost seal.

c. Slide the seal out of the recess in the bearing housing and off the shaft.

Inpro or Magnetic Seal Replacement (Exhaust End)

a. Clean drive end of the shaft and remove any burrs that could damage the seal

O-ring.

b. Lubricate the shaft and seal O-ring with turbine oil to facilitate seal insertion

on the shaft.

c. Slide the seal onto the shaft, placing it into the recess in the lower bearing

housing half.

d. Replace the upper bearing housing half according to the procedure specified in

Section L.6.

e. Replace half-coupling on the shaft.

Reassemble rotor into the turbine along with the steam seals.

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Figure L-9. Bearing Housings with Inpro/Seals

L.8

Bearing Housing Removal and Replacement

SST bearing housings are attached to the lower turbine casing with bolts. Two

dowel pins on each housing, maintain their position. Alignment of bearing

housings to the casing and to each other is essential for vibration-free operation and

long bearing life. Bearing housings are accurately aligned at the factory prior to

pinning. Should it be necessary to remove or replace a bearing housing, it is

essential that the alignment be checked and corrected, if necessary, prior to re-

installation of the rotor.

Bearing housing alignment is a precision process that requires skill, experience,

and precise measurement. If there is any question regarding the ability of site

personnel to properly align bearing housings, Dresser-Rand recommends that a

factory-trained serviceman be engaged to perform the service. Contact your

Dresser-Rand manufacturer’s representative or the Dresser-Rand factory to

schedule a service visit.

L.9

Turbine Rotor & Turbine Wheel Removal and Replacement

Refer to the following figures:

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M-0

SST Turbine, General View

M-1

Trip Throttle Valve Assembly

M-2

Governor, Mounting Housing, and Trip Components

M-3

Gland Sealing Elements

M-4

Hi-Cap Bearing Case Assembly, Exhaust End

M-5

Bearing Housing Assembly, Exhaust End

M-6

Bearing Housing Assembly, Steam End

M-7

Bearing Housing Assembly, Steam End

M-8

Case, Rotor and Mechanical Gland Seals

M-9

Case, Rotor and Carbon Ring Gland Seals

L.9.1

Turbine Rotor Removal & Replacement

The governor, turbine cover, casing labyrinth seals (if so equipped), and carbon

rings must be removed or disassembled to remove the rotor.

Turbine Rotor Removal

a. For turbines where the governor is coupled to the shaft, remove the steam end

bearing case cap; then uncouple and remove the governor.

(See longitudinal

section, Appendix A). For a gear driven Woodward governor, disconnect the

governor linkage without disturbing the length of connecting rod, remove bolts

that fasten the governor to the housing and lift off the governor.

b. Remove the over-speed trip collar according to the procedure specified in

Section L.14.

c. Remove upper halves of bearing housings according to the procedure specified

in Section L.6.1.

d. Remove the top half of the turbine case according to the procedure specified in

Section L.3.

e. Remove shaft packing according to Section L.5.

Remove cap from the exhaust end bearing case and steam end bearing case (if

not already removed in step 1.

g. Remove both main bearing top halves.

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h. Arrange a suitable support for the rotor assembly. Verify that turbine wheel

blades and bearing journal surfaces on the shaft will not make contact with any

surrounding object. Verify that the assembly will not roll off the support.

Use slings and a crane or hoist to lift the rotor assembly just out of the lower

half of bearings; then remove lower half of bearings. Use extreme care when

lifting the assembly to avoid damaging the wheel, blades, shaft, or sector.

Place rotor assembly on the support.

Turbine Rotor Replacement

Verify that the interior of the turbine casing is clean and that all foreign objects

have been removed.

Clean or replace journal bearings (if so equipped) and lubricate journal area of

the shaft to prevent scratching or scoring.

If so equipped, place lower journal half into the bearing housing. Position oil

rings so that they fit into openings provided in the bearing housings.

Using slings and a crane or hoist, lower the rotor assembly into the casing. Use

care to avoid damage to the wheel, blades, shaft, or sector.

Check clearance between first wheel and nozzle ring. This clearance is

obtained by properly locating the thrust bearing. See figure L-8 and thrust

bearing adjustment procedure in section L.6.2.

Replace casing labyrinth seals (if so equipped) according to the procedure

specified in Section L.5.

Replace turbine cover and gland housing upper halves

(if so equipped)

according to the procedure specified in Section L.3.1.

Replace the sleeve bearing upper halves (if so equipped) and bearing housing

upper halves according to the procedure specified in Section L.6.

Replace the governor mounting housing

Replace over-speed bolt trip collar according to the procedure specified in

Section L.14.

Replace governor drive coupling governor and associated linkage according to

the procedure specified in Section L.12.

L.9.2

Turbine Wheel Removal and Replacement

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This operation is to be referred to Dresser-Rand service facilities.

CAUTION

DO NOT allow the heating FLAME TO IMPINGE on turbine

BLADES, as this could anneal and WEAKEN them.

WARNING

Exercise appropriate CAUTION in handling the HOT WHEEL

during disassembly and assembly.

CAUTION

Be certain to assemble the wheel and shaft with THE

SHORTER BLADES TOWARD the NON-DRIVE END OF THE

SHAFT. Otherwise, the rotor cannot be installed.

L.9.3

Turbine Rotor Balancing

Whenever a wheel or shaft is replaced, the wheel and shaft subassembly should be

dynamically balanced. This procedure must be performed by a Dresser-Rand

repair facility.

L.10

Nozzle Ring Removal and Replacement

Nozzle rings contain one or more nozzles which expand the inlet steam to a lower

pressure, creating the necessary kinetic energy (velocity) at the entrance of the first

wheel blading.

L.10.1 Nozzle Ring Removal

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After the rotor and guide ring have been removed from the lower half turbine

casing—

a. Loosen and remove nozzle ring cap screws. This may, at times present

a problem. Broken screws will have to be extracted or drilled out.

Note: When nozzle ring is secured with inner and outer bolts, no caulking

strip is used.

b. The nozzle ring may now be lifted out of the casing. Mark the ring to

identify its location if reused (upper or lower half).

L.10.2 Nozzle Ring Replacement

Nozzle rings are caulked in at the outer periphery and bolted to the steam ring

nozzle bolting face of the main casing when a single row of bolting is used. When

a double row of bolting is used, there is not a caulking strip.

a. Identify the upper and lower half nozzle ring. If necessary check that the

valve port bridge walls match their seal surfaces using bluing or white lead.

b. Check that the clearance holes in the nozzle ring and tapped holes in the

steam ring face agree.

c. Thoroughly clean the sealing surface at the steam ring face. If the

surface is smooth, the most common sealing compounds are Turbo R or

Turbo 50. If the surface is rough, use Copaltite. If these compounds are

not available, use a key paste or a mixture of graphite and oil. If none of

these compounds is available, call Dresser-Rand Technical Support.

d. Bolt the nozzle ring half in place. The cap screws should be pulled tight

but not over-tightened. If Allen wrenches bend during tightening, the

screws are overstressed and their heads may snap off when the unit comes

up to temperature. Over-tightening of screws must be avoided. Prick-

punch head clearance holes at four positions so that cap screw heads (if

broken off) cannot come out into the steam path.

L.11

Hand-valve Removal and Replacement

Hand-valves are optional items. Depending on steam conditions, required power

and speed, and initial customer requirements, the turbine may incorporate no hand-

valves, one hand-valve, or two hand-valves.

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The purpose of hand-valves is to isolate a nozzle or group of nozzles from inlet

steam, thereby allowing the turbine to operate at reduced power output without

excessive throttling. When operated at reduced power in this fashion, the turbine is

more efficient than it would be if all nozzles were active.

Hand-valves should be either fully open or fully closed, never in between.

Operating with a partially closed hand-valve is not only inefficient, but could result

in steam cutting of the seat resulting in excessive leakage. When putting the unit

into operation, do not close a hand-valve tightly until the turbine is up to operating

temperature and all parts are evenly heated. The reason for this is that the material

of the valve stem is subject to greater thermal expansion than the turbine casing,

and if the valve is closed tightly when cold, it may lock the valve in the closed

position making it difficult to open.

Refer to Figure L-10, Hand-valve Assembly.

L.11.1

Hand-valve Removal

WARNING

Close and tag inlet and exhaust isolating valves and open

drains to depressurize the turbine casing and steam chest

before maintaining hand-valves.

Note: Removal of the hand-valve is done from inside the turbine case.

a. Remove the turbine casing cover and bearing case covers, uncouple the turbine

rotor, and remove the carbon rings. See instructions in other sections of this

manual for these steps.

b. Remove the turbine rotor. Remove the nozzle ring.

c. Once the nozzle ring is removed you can see the hand-valve seat (761). Pull out

the hand-valve seat. The fit is on-line to 0.004” loose.

d. Remove the hand wheel (758). Remove the hand-valve bonnet (750).

e. Push the stem and disc assembly out towards the inside of the turbine. Remove

the old hand-valve packing (754). Note: Count the rings removed.

f. Clean the seat area, nozzle ring face, and all areas that might have sealant.

L.11.2

Hand-valve Replacement

a. Inspect the stem and disc assembly. Hand-valve collar (752) should be tight

and staked to the disc (751).

b. Insert the new stem and disc assembly into the turbine hand-valve location.

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c. Make sure the seat (761) and the bore of the turbine case are clean. Insert the

seat into the hole where it was removed. If there is a slight interference, cool

down the seat in a freezer or with liquid Nitrogen.

d. Install the nozzle ring in accordance with instructions in other sections of this

manual.

e. Assemble new packing (754). Put in the same number of packing rings as

were removed.

Assemble bonnet (750) and hand wheel (758). Tighten the bonnet to compress

the packing until you feel a slight drag on the stem when you screw it in and

out.

L.11.3

Reassembly of the Turbine Rotor and Upper Half Casing

a. Clean all surface areas (turbine casing split-line, bearing case split-lines, etc).

b. Assemble the carbon rings, turbine cover, and bearing case covers per

instructions given in other sections of this manual.

L11.4

Handvalve Adjustment

a. One steam is admitted into the unit, re-tighten the hand-valve bonnet so there

is no steam leaking out of the steam area. This might have to be done again

when there is full pressure inside the casing to prevent leakage at the high

internal pressure.

b. The valve stem should be screwed fully closed or fully open. It should never

be partially open or closed.

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In the event that the governor exhibits operational problems, Dresser-Rand

recommends that the governor be removed as a unit and returned to the factory for

repair or overhaul, as required. In the meantime, a replacement oil relay governor

can be quickly and easily installed to keep the turbine in operation. The Dresser-

Rand factory maintains a stock of certain TG replacement governors for rapid field

delivery, and is equipped to perform comprehensive repair, overhaul, and testing of

oil relay governors.

For shipment, care should be exercised to support the governor by its mounting

flange and not by its shaft extension.

Some governors are direct-drive types coupled to the end of the turbine shaft by

couplings, as shown in Figure L-11. Others, due to speed requirements, are

connected by right-angle gear reduction units, as shown in Figure L-12.

L.12.2

Governor Removal (Direct Drive)

a. Drain oil from governor (300) at drain.

b. Disconnect connecting rod

(1075) at governor lever

(445) by removing

connecting rod end (1070). Do not disturb position of rod end (1070) bearing

on rod (to preserve open/close stroke adjustment).

c. Rotate turbine shaft (1), if necessary, to disengage coupling hub (303) by

loosening coupling setscrew.

d. Prop or support governor (300); then, unbolt governor from mounting housing

(201) and slide governor out of mounting housing. Be careful not to lose the

governor key.

e. Remove governor trip latch (446) (if same governor is not to be used as

temporary replacement) by loosening its setscrew.

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Figure L-11. Direct Drive Governor Assembly

L.12.3

Governor Replacement (Direct Drive)

a. Install governor trip latch (446) and tighten lever set-screw securely.

b. Slip coupling spider between jaws of coupling (303) hub on turbine shaft

extension.

c. Install coupling hub (303) on governor shaft.

d. Slide governor (300) into place on mounting housing (201), verifying that

coupling (303) engages properly.

e. Install and tighten screws to secure governor to mounting housing (303). There

should be 1/16 inch (1.6 mm) play for the coupling spider between coupling

hubs. Coupling access is available through the open side of the mounting

housing. Tighten screw to secure coupling.

Reconnect connecting rod (1075).

g. Remove governor breather cap and fill governor with oil to proper level

indicated on sight glass.

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h. Rotate turbine shaft (1) slowly by hand to ensure that governor and coupling

are free to turn when placed in operation.

L.12.4

Governor Removal (Gear Drive)

a. Drain oil from governor (300).

b. Disconnect connecting rod

(1075) at governor lever

(445) by removing

connecting rod bolt. Do not disturb position of rod end bearing on rod (to

preserve open/close stroke adjustment).

c. Remove cap screws securing governor (300) to gearbox (316) adapter; then,

lift governor vertically from adapter. The coupling (303) will remain on the

governor shaft at removal. Do not remove governor lever or coupling from

governor if same governor is to be installed again. If a new governor is to be

installed, transfer lever and coupling (with keys) to new governor. The lever

and coupling are secured to governor shafts by setscrews.

Note: The coupling, which joins the governor and gearbox shafts, is supplied with

the gearbox.

L.12.5

Governor Replacement (Gear Drive)

a. Verify that coupling and keys are installed on governor shaft, and that the

governor lever is mounted to its shaft at the side of the governor.

b. Lower governor (300) on gearbox (316) adapter with coupling key slots

positioned to allow mating of keys and key slots of shaft and coupling (303) as

governor and adapter flanges meet.

c. Rotate governor to align cap screw holes; then, install cap screws tightly.

L.12.6

Governor Drive Gearbox Removal

The governor (300) must be removed according to the procedure specified in

Section L.12.4, above, before the gear (310) and governor drive shaft (306) can be

removed.

a. Drain oil from steam end bearing case (200).

b. Remove pin (304) from coupling (303) to release coupling from governor

drive shaft (306).

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c. Remove lock-nut (313) and lock washer (312) retaining gear onto governor

drive shaft (306). Slide gear (310) up off of shaft (306), being careful not to

lose key (311).

d. Remove shim (308) being careful to document order of removal/replacement.

e. Remove snap ring (318) retaining bearing into housing (301). At this point the

governor drive shaft (306) can be extracted from the housing (301).

f. Prop or support governor drive shaft (306) in a vice being careful not to scar the

shaft surface and remove the snap ring (318) retaining the ball bearing (339).

At this point both ball bearings (339) and (305) can be pressed from the

governor drive shaft (306) for replacement.

The Dresser-Rand factory maintains a stock of replacement governor drive shaft

parts for rapid delivery to the user, and is equipped to perform complete repair and

overhaul service on gearboxes.

L.12.7

Governor Drive Gearbox Replacement

a. Install governor drive shaft (306) into housing (301) and install snap ring

(318). Replace shim (308), locate key (311) into slot on governor drive shaft

(306) and install gear (310), lock washer (312) and lock-nut (313) securing

gear onto governor drive shaft (306).

b. Install coupling (303) and pin (304) into and onto governor drive shaft (306).

c. Before installing the governor, check and record the backlash of the new gear.

In future inspections, use this dimension as a guide in determining the

necessity for replacement. If backlash is questionable use Dyken layout blue

or printers ink to check for proper mesh of gears. When a good mesh is

indicated, the gear may remain in service.

c. Mount governor (3004) onto housing (316), verifying that the splines on the

governor shaft slide into the coupling (303) easily. Install mounting bolts to

secure governor (300) onto housing (316).

d. Fill hydraulic governor with oil. Refer to Woodward Bulletin

25071 in

Appendix B.

e. Fill steam end bearing case (200) with recommended lubricant to required

level, as indicated by oil sight gage plug.

L.12.8

Governor Valve Travel and Linkage Adjustment

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Refer to the following figures:

M-1

Trip Throttle Valve Assembly

M-2

Governor, Mounting Housing, and Trip Components

L-11

Direct Drive Governor Assembly

L-12

Gear Drive Governor Assembly

L-13

Trip Valve Linkage

Adjustment of the linkage between the governor and throttle should be carried out

whenever linkage components, or the governor itself, are replaced. Rig the throttle

linkage as follows:

a. Check that the governor linkage is approximately at right angles to governor

connecting rod.

(See upper view of figure L-13). Adjust the length of the

connection rod as necessary.

b. Back off the lock nuts on both sides of the governor lever block.

c. Pull the connecting rod out of the Woodward governor as far as it will go.

d. Push the connecting rod back toward the governor 3/16”/4.76mm. (To hold

this position while making the adjustment, place a block equal to the existing

clearance between the connecting rod end and the mating fitting on the

governor—see lower view in Figure L-18.

e. Push the valve stem in until the valve just seats.

f. Tighten the lock nuts on both sides of the governor lever block to secure

the ajdustment.

L.13

Trip and Throttle Valve Maintenance

CAUTION

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If the turbine is equipped with a throttle or trip valve

manufactured by a party other than Dresser-Rand refer to the

accessory documentation section of this manual for installation,

operation, and repair and maintenance instructions.

Refer to the following figures:

M-1

Trip and Throttle Valve Assembly

M-2

Governor, Mounting Housing, and Trip Components

L-13

Trip Valve Trip Linkage

L-14

Throttle Valve Trip Linkage

The design of the Dresser-Rand trip and throttle valve assembly permits routine

maintenance (disassembly and assembly) procedures while still mounted on the

turbine and without disconnecting the inlet piping. For major overhaul or

necessary machine work, remove the valve as indicated below.

WARNING

BEFORE SERVICING ANY COMPONENT of the combo valve,

verify that the ISOLATING VALVE in the INLET LINE is

CLOSED AND TAGGED. If the turbine is connected to the

exhaust steam header, CLOSE the ISOLATING VALVE in the

EXHAUST LINE AND TAG IT. OPEN ALL TURBINE DRAINS

to ensure venting of all pressure before disassembly begins.

CAUTION

In the following procedures, remove and replace all parts slowly

and carefully to avoid damage (digs, bends, scoring, chipping,

etc.) to conditioned surfaces. DO NOT use excessive force to

remove parts. Use backup bracing for unsupported parts when

taper pins or dowels are removed by hammer and drifts.

L.13.1

Valve Removal from Turbine

The steam strainer should be removed and cleaned at least once a year and

replaced every three years. Since it is necessary to remove the governor

valve before the strainer can be withdrawn, the governor valve and its seats

should be inspected and reground if necessary. To replace either the

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governor valve or the steam strainer, proceed as follows:

(See Figure L-

14).

Remove valve adjusting nut and washer.

Note: Do not disturb settings of lock nuts and connecting rod-ends (17 and 19) on

rod (18) unless parts need to be replaced. These are factory-set to provide

the required stroke for the rod.

b. Remove snap ring from the governor lever pin; then remove the pin and

carefully slide the governor lever off the governor valve stem.

c. Remove the nuts that secure the steam chest cover to the steam chest and

carefully remove the cover without contacting the valve stem.

d. Pull out the governor valve (see governor section, Appendix A).

e. Remove bolting at turbine flange; then, lift valve by slings and hoist to service

area for further disassembly.

Remove as an assembly together with the steam strainer.

g. Perform necessary maintenance and reassemble by reversing the removal

procedure.

h. After completing installation, set the following:

Overspeed Trip

Overspeed Trip Linkage

Governor Valve Travel

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Finger 22

3 Valve Seat Bushing

Stem

Strainer

Figure L-13. Overspeed and Governor Valve Linkage

Legend

15. Lockscrew

1. Cap

8. Case - Steam End

16. Lever - Governor

2. Lever

9. Steam - Bellows

17. Pin

3. Lever - Trip

10. Bracket - Low Oil Trip

18. Rod End

4. Lever - Trip Connection

11. Low Oil Trip

19. Rod - Connecting

5. Rod - Trip Connection

12. Governor Cup

20. Shaft - Trip

6. Plate - Top

13. Adjusting Screw

21. Collar

7. Latch - Trip Assembly

14. Emergency Weight

22. Trip Finger & Lever

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Figure L-14. Throttle Valve Linkage

Legend

1. Bushing - Valve Seat

8. Stem - Valve

14. Cover - Steam Chest

2. Bushing — Valve Stem

9. Pin

15. Lever - Governor

3. Valve

10. Bearing

16. Pin

4. Steam Chest

11. Bushing - Valve

17. Rod End

5. Gasket

Stem-Outer

18. Rod- Connecting

6. Bracket - Governor Lever

12. Block - Pivot

19. Rod End

7. Bushing - Valve Stem - Inner13. Block - Sliding

20. Lever

L.13.2

Woodward TG Governor Valve Travel Setting

a. Remove pin that connects the governor lever to the connecting rod end.

(See Figure L-15.)

b. Push the governor lever in until valve just seats and hold this position.

c. Push connecting rod toward the valve closing direction (see arrow on

illustration) as far as it will go and hold this position.

d. Adjust the length of the connecting rod so that the hole for the pin in the

rod end is approximately 1/8”/3.75mm beyond the mating hole in the

governor rod.

e. Release the connecting rod and insert the connecting pin.

L.13.3

Woodward TG-13L Governor with Fisher Control

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The Fisher pneumatic speed mechanism acts in conjunction with the Woodward

TG-13L governor to adjust the turbine speed to refined limits. If speed re-

adjustment is desired, re-locate the pin to another hole in the lever (see Governor

Speed Control Schematic, Appendix A).

The Fisher control can be used as a direct or reverse type control; either to increase governor

speed settings as control air pressure signal increases, or the reverse type to increase governor

speed as control air pressure signal

decreases.

Figure L-15. Governor Valve Travel Setting - Woodward TG Governor

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L.14

Emergency Valve Maintenance

WARNING

BEFORE SERVICING ANY COMPONENT of the Overspeed

Trip Mechanism, verify that the ISOLATING VALVE in the

INLET LINE is CLOSED AND TAGGED. If the turbine is

connected to the exhaust steam header, CLOSE the

ISOLATING VALVE in the EXHAUST LINE AND TAG IT.

OPEN ALL TURBINE DRAINS to ensure venting of all pressure

before disassembly begins.

The overspeed trip mechanism may be readily disassembled or assembled at a

workbench and then mounted to the turbine as a subassembly. Prerequisites for this

process are removal of the governor and coupling according to the procedure

specified in Section L.12, followed by removal of the overspeed trip collar (90)

from shaft (1), as described below.

It is important that the entire emergency trip system be properly adjusted and free

of binding or lost motion. The operation of the overspeed trip should be tested as

often as possible, especially at times that maintenance is performed and a

permanent record should be kept of these tests. The over-speed trip should

function to shut down the turbine within 2% of the speed specified on the turbine

data sheets. If the operational tests in Section I.6 indicate a requirement for

adjustment, proceed as follows:

L.14.1

Governor Cup Removal

Refer to the following figures:

L-13

Overspeed and Governor Valve Linkage

L-14

Throttle Valve Linkage

L-15

Governor Cup Assembly

a. Gain access to the overspeed governor cup.

For turbines with a Woodward gear driven governor - remove bearing

case end cover.

For turbines with a Woodward governor that is coupled to the shaft -

remove the steam end bearing case cap.

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b. Manually rotate the turbine shaft (1) until the lock screw (P/N 15, Figure L-13

or P/N 92, Figure L-15) is accessible; then loosen the lock screw.

CAUTION

If the Overspeed Governor Cup Assembly is replaced, the rotor

may need to be re-balanced with the new assembly attached.

Figure L-17. Governor Cup Assembly

Legend:

90. Cup - Governor

94. Spring

91. Screw - Adjusting

95. Bushing - Weight

92. Set Screw

96. Ring - Retaining-Open type

93. Weight

97. Ring - Retaining-External type

b. Using a suitable spanner tool, turn the adjusting screw (91) clockwise to raise

the tripping speed or counterclockwise to lower, as necessary.

c. Tighten the lock screw (15 or 92) (setscrew) securely to lock the adjustment

position, then repeat the over-speed trip test (see warning below).

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WARNING

The overspeed trip assembly should be locked in place before

starting the turbine. Four checks to make are as follows:

1. The overspeed governor cup must be tightly screwed into

the shaft.

2. If supplied, one of the tabs of the lock-washer is bent into

the miller slot of the overspeed cup.

(The overspeed cup will

have two milled slots for the tabs of the lock-washer, but it will

only be possible to line up one of the tabs. This is due to the

fact that the tabs are not symmetrically located around the

outer diameter. There is no need for concern as long as one of

the tabs can be completely bent over into the slot.)

3. If the overspeed cup has drilled and tapped holes for half

dog point set screws, the shaft must be drilled at final assembly

with the overspeed cup in accordance with the table below to

ensure the tip of the dog point locks into the shaft. The set

screws must be tightened and staked into place.

4. The run-out of the cup must also be checked and adjusted

to within 0.002 inch (.05 mm) total indicated run-out.

L.14.2

Governor Cup Replacement

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CAUTION

The adjusting screw/spring combination has been pre-set at the

factory for the trip speed originally set when the turbine was

shipped. Refer to Section L.14.7, Trip Linkage Adjustment, if

minor trip speed changes are to be made.

WARNING

Adjusting Screw (91), spring (94), and setscrew (92) are a

FACTORY-CONFIGURED SET, selected to obtain the proper

trip speed for a specific turbine. DO NOT MIX OR

INTERCHANGE THESE PARTS with similar parts from other

turbines or attempt to modify these components. Consult your

local Dresser-Rand manufacturer’s representative or the factory

if replacement parts are needed.

L.14.3

Trip Mechanism Disassembly

For 4” and 6” trip and throttle valve systems, the clearance between the overspeed trip

lever (Figure L-13) and the emergency weight (P/N 14) or (P/N 93 in Figure L-14) is

properly set at the factory for 0.060”/1.524mm plus or minus 0.010”/0.254mm. Gain

access to the over-speed governor cup as described in the preceding section L.14.1.

For 4” and 6” Venturi trip systems, the clearance between the over-speed trip lever

(figure L-13) and the emergency weight (P/N 14 or P/N 93) is properly set at the factory

for (0.090”/2.286mm plus or minus 0.010”/0.254mm. Gain access to the overspeed

governor cup as described in section L.14.1.

Rotate the turbine shaft (1) to position the overspeed weight adjacent to the overspeed

trip lever and measure the clearance. If adjustment is necessary, proceed as follows:

a. Loosen lock screw that secures the valve lever trip connection to the valve

spindle.

b. Slide valve lever connection along the valve spindle away from the steam

chest to increase the clearance, toward the steam chest to decrease the

clearance.

c. Tighten the lock screw to securely hold the valve lever connection.

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L.14.4

Emergency Valve Travel

a. Unlatch valve lever (P/N 3, Figure L-13) to close emergency valve.

b. Manually pull out on the governor linkage to close the governor valve. On the

turbine, it may be necessary to remove the pin from the connecting rod. (See

lower view of Figure L-18)

c. With the governor valve fully closed, raise the valve lever until the emergency

valve will not open further (do not spring the valve lever).

d. Measure the clearance between the latch surface of the valve lever and the

latch surface of the trip lever. The clearance should be approximately ¼”/6.35

mm.

e. If adjustment is required, loosen the lock screw in the valve lever connection;

then reposition the valve lever connection and serrated valve spindle clockwise

or counter-clockwise as necessary to obtain the correct clearance.

NOTE: After making this adjustment, it will be necessary to re-check the

setting of the over-speed trip linkage.

L.14.5

Emergency Valve Removal and Replacement

a. Remove governor valve and steam strainer as described in section L.13.1.

b. Remove lock screw in the valve lever connection; then slide the valve lever

connection off the serrated valve spindle.

c. Remove access plug in the steam chest located above the valve spindle; then

remove the lock screw that secures the valve spindle to the valve link.

d. Remove access plug in the steam chest in line with the valve spindle and

withdraw the valve spindle.

e. Remove the valve link by sliding up and away from the valve stem.

d. Remove the valve portion of the assembly and inspect the valve seat.

NOTE: If the valve seat must be replaced, the steam chest must be removed from

the turbine.

e. Re-assemble and install the emergency valve by reversing the removal

procedure.

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Overspeed trip

Overspeed trip linkage

Governor valve travel

Emergency valve travel

L.14.6

Trip and Throttle Valve and Steam Strainer

The following are procedures for replacement of the steam strainer:

a. Close the main steam valve.

a. Disconnect the pressure and drain line connections at the oil cylinder flanges.

c. Disconnect the linkage from the governor lever.

d. Remove the bolts that fasten the trip throttle valve body to the valve body

cover.

e. Remove the bolts that fasten the valve body cover to the valve body; then lift

off the valve body cover.

Lift out the emergency valve guide.

g. Pull out the steam strainer.

h. Perform the necessary maintenance and re-assemble by reversing the removal

procedure.

For procedures on a vendor valve, see Appendix B.

NOTE: The 6” trip and throttle valve cover is equipped with a throttle screw that

regulates the amount of steam from the inlet side of the valve to the chamber

above the main disc. If chattering of the main disc is encountered when

opening the valve, it is necessary to increase the leakage to the chamber by

turning the throttle screw counter-clockwise. If, however, the hand-wheel

effort appears excessive, it can be reduced by turning the throttle screw

clockwise, thus decreasing the leakage to the chamber. A pipe tap is provided

in the cover to be used for a pressure gauge to check the pressure chamber

after the pilot valve has been opened. This leakage pressure should be

approximately 25% of the line operating pressure.

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Section M

Replacement Parts/Factory Service

M.1

Factory Replacement Parts

Dresser-Rand Turbine recommends that only Dresser-Rand-supplied parts be used

in Dresser-Rand turbines. The use of Dresser-Rand parts ensures that replacement

components are manufactured from the highest quality materials, to exacting

tolerances and specifications, thereby assuring safe, efficient, long-lasting, and

maintenance-free operation under service conditions for which the turbine was

designed and built.

Dresser-Rand and selected Dresser-Rand manufacturer’s representatives maintain a

supply of the most frequently requested spare parts for immediate shipment

worldwide. Parts requested less frequently can be manufactured quickly on an

emergency basis when required.

Your Dresser-Rand manufacturer’s representative can supply you with a stocking

list of recommended spare parts for your turbine or turbines, allowing you to stock

spare parts at your facility. Refer to Section M.4, Recommended Spare Parts.

M.2

Turbine Identification

Dresser-Rand SST turbines are marked with a serial number, which appears on the

nameplate and is also, stamped on horizontal flange of the inlet casing. This serial

number is used by the factory to identify the turbine and should be used in all

inquiries and parts orders.

M.3

Parts Identification

When inquiring to determine parts availability, or when placing an order for spare

parts, the following minimum information is required:

Item

Typical Example

Turbine serial number:

XXXX

Part description:

Shaft

Reference number:

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Section Drawing

LE-169235-N

If the turbine parts list is available, then the Dresser-Rand part number should also

be specified.

WARNING

Modification of, incorrect repair of, or use of non-DRESSER-

RAND repair parts on this turbine could result in serious

malfunction or explosion that could result in serious injury or

death. Such actions will also invalidate ATEX Directive &

Machinery Directive Certifications for turbines that are in

compliance with those European Directives. Refer to Section M

- Replacement Parts/Factory Service.

M.4

Recommended Spare Parts

The recommended spare parts for a turbine owner is provided in the service

manual. The inventory recommendation for spare parts is based on Dresser-Rand’s

long experience with turbine applications.

M.5

Ordering Parts

Contact your local Dresser-Rand manufacturer’s representative to order parts. Your

representative will be pleased to provide any assistance you may require, as well as

to quote prices and delivery dates.

The following information is required when placing a parts order:

Your purchase order number.

Complete billing, shipping, and marking instructions.

Turbine serial number--from nameplate or horizontal flange of inlet casing.

4. Turbine frame size--from nameplate, i.e., 300, 500, 700, etc.

5. Quantity of each part or assembly.

Part or assembly reference number from drawing, illustration, or text.

7. Section drawing the reference number was taken from.

8. Description of part or assembly.

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9. Dresser-Rand part number, if known (optional).

M.6

Service

Dresser-Rand Turbine maintains repair facilities on a worldwide basis to repair

equipment needs with OEM manufactured parts. When contacting Dresser-Rand,

please have your turbine serial number available.

Contact a service center nearest you by using the link below:

http://www.dresser-rand.com/contactUs.php

A Service Representative can also be dispatched to your site to assist you in start-

ups, general maintenance, and troubleshooting by using the same link (above).

Have your turbine serial number available along with a date for when services will

be required.

The Technical Support group at the factory can address your technical questions by

using the contact information below:

Dresser-Rand Wellsville Operations

37 Coats St.

Wellsville, NY 14895

USA Tel: (Int’l +1) 585-596-3100

Fax (Int’l +1) 585-593-5815

When contacting the representative or factory, please specify the turbine serial

number, frame size, nature of the problem or service requirement, and date that

service is required.

M.7

Revamps (Rerates)

It’s not uncommon for the requirements of the steam turbine to change due to a

process change, more product output, or just a need to reduce energy consumption.

Steam turbine can have a broad operating range. Powers and speeds can be

modified with simple internal hardware changes while still maintaining the same

steam turbine case and footprint.

If you would like to have Dresser-Rand review your equipment, please use the

contact information above the find the nearest service center or contact the factory

direct. Have your serial number available along with the new conditions you

would like to operate at.

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WARNING

Materials used in turbine construction (cast iron, steel, stainless

steel, special alloys) vary with steam conditions, speed, and

power. These materials were selected according to the original

rating of the turbine. NEVER attempt to re-rate a turbine without

the assistance of a Dresser-Rand manufacturer’s

representative and/or the factory. Misapplication of materials

could result in serious equipment damage and/or personal

injury.

M.8

Upgrades

Many of older turbines can be modified or upgraded to improve performance and

reliability. Improved designs in seals, bearings, controls, and blading can all be

incorporated into the existing machine when required.

If you would like to have Dresser-Rand review your equipment, please use the

contact information above and find the nearest service center or contact the factory

direct. Have your serial number available.

M.9

Factory Start-Ups

Authorized Dresser-Rand service representatives are available for start-up service

and to train operating personnel in the operation and maintenance of Dresser-Rand

steam turbines. An experienced service representatives will review your installation

prior to start-up, following established Dresser-Rand procedures.

Piping,

alignment, lubrication, overspeed trip, etc. will be carefully checked. Upon

commissioning the new installation, operating personnel will be trained.

Consult your Dresser-Rand manufacturer’s representative to schedule a start-up.

M.10

Parts Catalog

Refer to the applicable turbine cross sectional drawings included in the instruction

manual for a listing and location of the replacement part reference numbers used on

your turbine.

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Section N Miscellaneous

N.1

Low Ambient Temperature Applications of Single

Stage ASTM A216-WCB Carbon Steel Pressure

Casing Steam Turbines

Dresser-Rand has been asked to provide a quotation for steam turbines that may be

installed into an area with an ambient temperature of -30°C (-20°C) or less.

The quoted D-R single stage turbine is offered with ASTM A216 Grade WCB

carbon steel pressure casing material that will meet the Charpy V-Notch Energy

requirements of ASME Pressure Vessel Code Section VIII, Division 1, UG-84 as

required by API 611 for ambient temperatures -30°C (-20°F) or higher. The

pressure vessel bolting is ASTM A193 Grade B7, and nuts are ASTM A194 Grade

2H or ASTM A563 Grade A, which also meet the requirements of the Pressure

Vessel Code and API 611for ambient temperatures of -30°C (-20°F) or higher. If

the offered turbine is installed into an area with ambient temperatures of lower than

-30°C (-20°F), the equipment user must take precautions to insure that the turbine

casing be kept warm and/or be warmed prior to equipment start-up to meet the

requirements of ASME Section VIII, Division 1, UG84, as appropriate.

When a steam turbine is in operation, the casing temperature s above the

brittle/ductile transition temperature of the casing material. Therefore, a low

ambient temperature is not a concern. However, to insure that the low ambient

temperature does not result in damage or failure of the turbine and its accessories, it

must be installed, started, operated, and shut down as described in the Low

Ambient Steam Turbine Application Guidelines outlined below. If compliance

with these guidelines and acceptance of the offered standard materials is not

possible, consult Dresser-Rand for further discussion or an alternate material

offering.

Prior to the purchase of the turbine, the final equipment user, driven equipment

vendor, and Dresser-Rand shall agree to the special precautions necessary with

regard to low ambient conditions that can occur during operation, maintenance,

transportation, erection, commissioning, and testing.

Dresser-Rand shall assume no liability of any nature for the offered turbine if not

transported, erected, installed, started, operated, maintained, and shut down as

described in compliance with the

“Low Ambient Steam Turbine Application

Guidelines” outlined in this document.

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Low Ambient Steam Turbine Application Guidelines

Note these requirements apply to both API and non-API applications.

General:

When a steam turbine is to be installed where the ambient temperature could be -

30°C (-20°F) or lower, the following issues require special attention to insure that

the low temperature does not result in damage or failure of the turbine and/or its

accessories.

See the turbine instruction manual for additional turbine installation and

operational details and the accessory instruction manuals for their cold start/low

ambient precautions and recommendations.

Transportation:

The turbine is suitable for transporting to site, unloading, and placing in storage, or

transporting to site, unloading, and placing on its foundations, or moving from on-

site unheated storage to its foundations, only when ambient temperature is at or

above -30°C (-20°F).

Installation:

The turbine and its auxiliaries can remain out of service with no external source of

heat when the ambient temperature is at or above -45°C (-49°F), provided the

turbine is not disturbed when its metal temperature is below

-30°C (-20°F),

Turbine maintenance cannot occur unless the temperature of the turbine and all its

mechanical components is at or above -30°C(-20°F).

Turbine installation cannot proceed until the turbine and all its mechanical

components are t or above -30°C (-20°F). Alternatively, if the turbine components

are below -30°C (-20°F), the area musts be hooded and heated to raise the

component temperature above -30°C (-20°F).

Care must be taken to insure that the steam inlet and exhaust piping is properly

supported or equipped with flexible connections so they will not put excessive

force on the turbine when it is shut down. The turbine casing and inlet and exhaust

flange material are more prone to cracking when the ambient temperature is cold ad

their temperature is below the brittle/ductile transition temperature. This is of

increased concern if the piping is hot when the turbine is shut down and the inlet

and exhaust shut off valves are closed.

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All turbine condensate drain connections and steam piping low points must be

properly drained to insure all condensate can be removed from the turbine and

steam system during shot-down. Similarly, cooling water lines to bearing housings

and water coolers, bearing housing water jackets, and oil coolers must be equipped

with drains to insure that water can be removed during shut-down.

Failure to remove all water from the turbine casing, piping, cooler,, bearing

housing, etc. when temperatures are below freezing could result in failure of the

piping and various other components.

If oil reservoirs, oil or water piping, bearing housings, and other components are

heat-traced, all local safety regulations and electrical codes must be adhered to.

Lubrication:

Dresser-Rand offers a variety of lubrication systems including oil ring lubrication,

oil ring lubrication with circulating oil cooling, circulating oil lubrication, mist oil

lubrication, and force feed lubrication.

When the ambient temperature is 15°C (60°F) or lower, it must be ensured that the

lubricating oil will circulate and that cooling water, if required, does not freeze

during operation or shut-down. Heat tracing or insulation of oil lines, bearing

housing, oil tanks, and water cooling lines may be required. Lubricant type and

required oil viscosities for turbine equipment packages are defined in the certified

drawings and data package and the applicable operation and maintenance manuals.

Viscosities for turbine lubrication are application specific, and the required

viscosity may range from ISO 32 (32cSt@40°C (100°F) 150 SUS @40°C (100°F)

up to ISO 100 (100 sSt @ 40°C (100°F) 550 SUS@40°C (100°F),

Use of the correct lubricants at the correct temperatures and viscosities is critical to

the trouble free operation of the turbine and its accessory equipment.

Accessories:

Some turbine accessories may require installation, heat tracing, special lubrication,

or adjustments for use in low ambient conditions. Others may require installation

into heated locations or preheating before use. The accessory instruction manuals

or accessory vendor must be consulted for additional guidance and precautions.

A partial list of typical turbine accessories might include governors, gauges, oil

pumps, control panels, instruments, reduction gears, lube oil systems, couplings,

steam piping, valves, solenoid valves, tachometers, ejectors, condensers, etc.

Turbine Start-Up:

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Warming the Turbine Pressure Casing:

If metal temperature is at or below -30°C (-20°F), a warm-up of the complete

turbine must be performed prior to start-up, including the use of hooding and space

heating to elevate the metal temperature of all steam-contacted components to a

temperature of at least -30°C (-20°F) prior to the introduction of steam to the

turbine.

If metal temperature is above -30°C (-20°F), steam from the client’s exhaust steam

header piping may be used to preheat the cold back pressure turbine prior to start-

up. If exhaust steam is not available for this purpose, a small steam bypass line,

equipped with a valve, may be installed around the inlet block valve or start-stop

valve to allow preheating of the turbine casing with a small flow of inlet steam.

Allow the turbine casing to reach 15°C (60°F) or exhaust steam temperature before

proceeding further.

During warming, all turbine casing and associated steam piping drain valves must

be opened to allow liquid to drain from the turbine casing and its associated steam

piping. Take special care to insure all liquids are drained prior to closing the

valves for turbine start-up.

Prepare the Lubrication System for Start-Up

If the ambient temperature is less than 15°C (60°F), lubricating oil and, if supplied,

the lubrication system and oil piping must be warmed to 15,C (60°F) to insure that

the oil will flow to the bearings and back to the oil reservoir or oil tank.

For ring-oiled turbines, the oil temperature should be such that the oil rings will

turn and pick up the oil. This may require that a hot liquid be circulated through

the bearing housing “cooling” water jackets.

“Cooling water,” if less than 15°C

(60°F), which may be required during normal turbine operation, should not be

applied to the bearing housing water jackets until the bearing housing temperature

exceeds 15°C (60°F), which may be required during normal turbine operation. For

turbines equipped with pressure lubricating or circulating oil systems, the lubricant

must be warmed to a viscosity such that the oil pump will prime and deliver

lubricant to the turbine bearings. His may be accomplished by use of a steam

heating coil or electric heating element. If electric heating elements are used, the

watt density should not exceed 23W/in² (3.5W/cm²), and a sheath temperature of

100°C (212°F) to avoid carbonizing the oil. After the lubricant is warmed, it must

be circulated throughout the entire lubrication system by means of a hand, motor,

or steam driven pump to warm all the associated lubrication system components

prior to turbine start-up.

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After heating the lubricating oil or determining that it does not require heating, start

the turbine per the instruction manual. Turn the turbine over slowly for a short

time, insuring that the oil rings are turning and/or the lubrication system is

delivering lubricant to the turbine bearings.

Operation:

Operate in accordance with normal operating routine, except that to maintain

suitable lubricating oil temperature and viscosity, it may be necessary to heat the

oil instead of cool the oil, especially if there are long un-insulated or unheated oil

lines between the turbine and a remote lubrication system.

With some turbine speed governors, a change in the governor oil viscosity may

have an effect on the speed of the turbine. Therefore, when operating a turbine in

low ambient temperature, it may be necessary to make manual adjustments on the

speed governor.

Shut Down

After the unit is shut down in accordance with the instruction manual, special care

must be taken to insure that all water is drained from the steam lines, turbine

casing, bearing housing water jackets, valves, oil coolers, etc. Freezing water in

the turbine or its associated systems can cause major damage or problems during

the next turbine start-up. Any lubricant or accessory heating system should be

turned off to avoid overheating unless advised otherwise by the manufacturer’s

instruction manual.

If there is steam from other processes in the exhaust piping, leave the exhaust valve

open. If the turbine is to be shut down or a short period of time or is on standby,

thereby avoiding the need to preheat the pressure casing on restart. Case drain

valves should be left open.

When properly drained of water, the turbine and its auxiliaries can remain out of

service with no external source of heat when the ambient temperature is at or above

-45°C (-49°F) as long as the turbine is not disturbed when its metal temperature is

below -30°C (-20°F). Turbine maintenance cannot occur unless the turbine and all

is mechanical components are at or above -30°C (-20°F).

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N.2 “Quick” Start,”Fast” Start, “Automatic” Start

Dresser-Rand Single Stage Steam Turbines

In the case of a “quick” start when the turbine is not thoroughly warmed nor

gradually brought up to the minimum governor speed, the principal areas of

concern are: (1) water slugging (2) bearing lubrication, (3) rotor acceleration rate,

and especially (4) sudden temperature differentials across the turbine.

1 Water Slugging

Since the velocity of a water particle passing through a turbine is low relative to the

steam and rotating blade velocity, such particles can cause extensive damage as

they impinge on the rotating blading. Furthermore, the downstream force

generated by such particles impinging on the rotor blading can be high enough to

cause thrust bearing failure. The warming of a steam turbine allows for

vaporization and removal of condensate in the steam inlet line ahead of the turbine

and in low points of the casing.

2 Lubrication

Without immediate and constant oil feed, the heat generated by the shaft in the

turbine bearings, unless properly dissipated, can cause bearing failure. Oil ring

lubricated bearings provide immediate lubrication as the shaft begins to turn, so

long as the proper oil level is maintained in the bearing housings. With pressure

lubricated bearings, the lubrication system must be arranged such that oil fills the

supply lines and feeds the bearings when the shaft begins to turn.

3 Acceleration Rate

With steam turbine applications that are started with no load, the acceleration rate

of a low inertia rotating element can be so high that the control system response to

close the steam admission valve does not react prior to overspeed trip. This

particularly true of the turbine generator sets which may also require limited

frequency variations in the electrical system. In instances such as this, a ramp

effect on governor valve closure may be built in the control system.

4 Temperature Differential

On turbines with built-up rotors, the disc-to-shaft allowance tends to decrease to

unacceptable limits with a 200°F (93°C) temperature differential between the disc

and shaft. The probability of such a condition existing is greater at approximately

five minutes after start-up, rather than immediately at start-up. Loss of shrink fit

can result in axial; or wobble movement of the disc on the shaft, possibly resulting

in turbine breakdown. The colder the unit at start-up, the greater the probability of

the temperature differential occurring. Since the utilization of forged discs in lieu

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of plate discs allows a higher shrink fit, we normally recommend the customer

consider using forged discs.

5 General:

The subject of “quick,” “fast,” or “automatic” start is not something new in the

steam turbine industry. Nor has Dresser-Rand decreased its engineering standards

for design of steam turbine shafts, bearings, or shrink fit of discs to shafts.

In general, reliability and durability are compromised by quick starting of a turbine

and will result in shortened overall turbine life. Frequent quick starts are

particularly severe on bearings and rotating elements. The more rapid the

acceleration rate, the higher are the transient loadings and the more severe are the

loading effects.

Dresser-Rand single stage turbines with standard construction are suitable for start-

up in five seconds provided the following conditions are met:

1. The inlet side of the turbine steam line must be trapped.

2. Proper lubrication of bearings must be provided.

3. The inlet temperature of the steam shall not exceed

750°F (399°C).

4. The differential temperature between inlet steam and

exhaust steam shall not exceed 350°F (177°C).

5. Back pressure shall be maintained on the casing during

shut-down.

(This in itself is not a recommended

operating condition due to possible shaft wire cutting or

carbon ring seal decay, but will keep the casing warm).

6. The operating speed of the turbine shall not exceed 6000

RPM.

7. The unit must be brought up under load.

In operating a turbine under the above conditions, the user must bear the

responsibility for bearing failure, loss of disc-to-shaft fit, and carbon ring decay.

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N.3 Dresser-Rand Standard Policy on Equipment Sound

Levels

It is Dresser-Rand’s intention to design and manufacture turbines with satisfactory

sound levels and work cooperatively with the user to make the overall installation

as quiet as possible. However, there are many environmental factors affecting

sound measurements which are beyond Dresser-Rand’s control. These might

include piping, room size, and other equipment or structures near the unit which

may tend to focus, reflect, or amplify sounds, as well as emit other sounds. In view

of this, Dresser-Rand is unable to guarantee noise levels other than to commit to a

willingness to assist the end user in corrective action (at end user’s cost) in cases

where a noise problem may be perceived to be present.

Expected sound levels for various types of Dresser-Rand-built equipment operating

at full load in a typical field installation are given below. Sound levels for the

turbine or gear alone isolated in a non-reflecting environment may be significantly

lower.

Octave Band Center

Expected Sound Pressure Levels

Frequency (HZ.)

(dB-Ref. 2 x 10⁵ Nm²

Single Stage

Multistage

Reduction

Turbines

gears

Acoustic Insulation 

Yes

105

104

103

102

125

250

500

1000

2000

4000

8000

Expected Over-All

(dBA)

The breakdown above gives maximum expected dB levels for each octave band

under typical operating conditions. Actual values for each octave band would

normally not equal all these maximum values. Hence, expected over-all sound

levels given above for each type of equipment are lower than the sum of the

individual (maximum) values.

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Section O

LOW VOLTAGE ELECTRICAL COMPONENTS

O.1 LIST OF POSSIBLE INSTALLED ELECTRICAL

PARTS AND THEIR APPLICATIONS ON 350/500/700

SST TURBINES

There are numerous combinations of electrical devices installed in some

turbines. Below is a listing of the possible electrical components found on SST

turbines in various configurations.

Electronic Governor. Some of the electronic governors used on the SST

turbines are manufactured by Tri-Sen, Compressor Controls Corporation, and

Woodward. Magnetic speed sensors, in most cases a quantity of two, are

installed either external to the exhaust end bearing case or internally or

externally on the steam end bearing case. The sensors read a gear internally

mounted on the rotor shaft and are wired typically by the customer to the

electronic governor input location. The electronic governor serves the same

purpose as a mechanical governor

(covered elsewhere in this manual) for

controlling turbine speed. The electronic governors provide an analog signal

output which can be utilized for remote customer DCS monitoring purposes.

Electronic governors also provide a means for relay control which can be

programmed to alarm and or trip other customer processes, as well as an option

for remote control via a switch panel either provided by the customer or

installed by Dresser-Rand. The electronic governors maintain turbine speed

through the use of an actuator. The actuator adjusts the governor valve in

response to the typical 4-20 mA signal received from the electronic governor.

A governor program is part of the documentation provided the customer

when an electronic governor is applied. Within the governor program are

the parameters, which are entered via keypad into the governor, when it is

programmed for operation.

Magnetic Speed Sensors. The electronic governors, tachometers, and

electronic over-speed protection require the use of speed probes to provide a

voltage-pulsed input for accurate turbine control. Each sensor is factory set to

the recommended adjustment gap between the probe tip and target.

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Limit Switch. The trip and throttle valve may have a limit switch mounted on

the valve to indicate closed position of the valve. The contacts can be

configured as normally open or normally closed per customer requirement.

Solenoid operated emergency trip valve. The over-speed tripping of the

turbine can be accomplished by a mechanical method covered elsewhere in

this manual. Electronic options are available to trip the turbine in an over-

speed condition through a solenoid valve which dumps the air or control oil

from the trip valve operational configuration. D-R recommends that the

solenoid valve be wired through an interposing relay to safely sustain the

current required for the solenoid valve operation.

A customer controls interface is required if it is desired to have a customer trip

signal incorporated into the emergency tripping of the turbine. This set of controls

needs to be accomplished via a trip string of series interconnected contacts, any of

which would de-energize the trip solenoid valve, thereby tripping the unit.

Vibration Monitoring. The turbine shaft radial movements at both the steam

end, exhaust end, and axial thrust bearing displacement can be accomplished

by vibration probe and proximitor hardware. In addition to the radial and

axial probes is the inclusion of a keyphasor probe for the Bently Nevada

asset monitoring equipment, which is D-R’s standard vibration monitoring

recommended vendor. The vibration probes are sized and installed in the

bearing cases for optimum length to clear accessories mounted on or near the

bearing case. Proximitors are typically shipped installed into a junction box

or loose. In some cases provisions only are provided the customer and

installation holes in the bearing cases are plugged.

Bearing Temperature Monitoring. D-R offers RTD or thermocouple

electronic bearing temperature monitoring capabilities. The bearings can be

equipped with the customer-specified instruments embedded within the

bearings by D-R. The temperature instrument wires exit through the bearing

case through Minco trade name seals where terminal heads are then

installed, providing wire termination points. Single and dual element

temperature instrumentation is available.

When provisions for future

temperature monitoring are requested by the customer, bearing cases have

installation holes machined and plugged so that bayonet style RTDs or

thermocouples could be installed at a later time.

Seismic Bearing Case Monitoring.

Accelerometers are available for

installation on the bearing cases, an alternative to the more sophisticated

probe and proximitor type of shaft monitoring. They monitor the rotational

vibration levels being transmitted to the bearing case.

Electronic Speed Monitoring (tachometer). Electronic tachometers are available for

local and remote speed monitoring. Some tachometers have programmable relays for

optional alarm and trip interface with customer DCS or PLC equipment. Self-powered

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tachometers are an available option. In most cases only one magnetic speed sensor is

required for use with the tachometer.

Electronic Overspeed Protection.

Over-speed tripping of the turbine can be

accomplished by a mechanical method covered elsewhere in this manual. Electronic

options are available to trip the turbine in an overspeed condition through a solenoid

valve which dumps the air or control oil from the trip valve operational configuration.

D-R recommends that the solenoid valve be wired through an interposing relay to safely

sustain the current required for the solenoid valve operation. There are three magnetic

pickup speed probes supplying signals to the over-speed protection device.

Over-speed trip devices are composed of three separate modules which are in communication

with each other. If one magnetic pickup fails, the unit will continue to operate with the two

remaining speed input signals but will trip when one of the signals exceeds the over-speed trip

setting on one of the modules. Normal operation compares the three speed signals and takes

the two highest out of the three signals to trip the turbine, hence the name two out of three.

During the programming of the over-speed device it is of utmost importance that the exact

number of targets being read by the speed probes be correctly entered.

Electronic/pneumatic throttle valve actuator and controls. Any SST turbine with an

electronic governor requires an actuator to be attached to the inlet governor valve to receive the

signals from the governor for valve movement and positioning and, if desired, provide valve

position feedback for monitoring. The most common actuator used, the electro-pneumatic

actuator, has a current to pressure interface where the electronic governor, via analog signal, is

electrically connected to the actuator and accurately controls its force/movement on the throttle

valve.

Electronic pressure transmitters. There are some instances where a remote pressure

measurement is required, which can be provided with an electronic pressure transmitter. There

are several types of communication methods available by which the transmitter can interface

with the customer PLC or DCS.

Electronic temperature transmitters. There are some instances where a remote temperature

measurement is required, which can be provided with an electronic temperature transmitter.

There are several types of communication methods available by which the transmitter can

interface with the customer PLC or DCS.

O.2

Electrical Component Removal and Replacement

CAUTION

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DO NOT perform work on any live electrical device or

component without a thorough lockout/tagout procedure in

place.

WARNING

Only professionally certified electricans are to be working on

the SST electrical components.

The upper half of the turbine exhaust and steam end bearing cases must be removed

to gain access to the shaft bearings and turbine rotor for RTD and thermocouple

access. See section L.3 for turbine case disassembly.

The procedure for removing and replacing the radial and journal bearings, which contain the

temperature monitoring hardware, is presented in section L.6.

Magnetic pickups are mounted on either the steam end or exhaust end bearing cases and can be

removed and replaced per field instruction procedures without the removal of the bearing cases.

Terminal heads can be removed from the pickup via the union and wiring removed from the

terminal blocks. In some instances the magnetic speed probes are installed inside the bearing

cases, in which case the bearing case must be disassembled to facilitate probe removal.

Limit switches indicating T&T valve position can be accessed from the outside of the valve and

removed by removal of the flexible conduit attached to the switch and removal of wiring from

the terminal blocks.

Vibration probes are mounted into the external cover of the bearing cases and can be removed

and replaced without turbine disassembly. Adjustment of the probes is accomplished with a

voltmeter set on DC voltage and turned until the voltage reads 9 volts DC whereby the locking

nut is secured in place.

The electro-pneumatic actuator is readily removable from the throttle valve body and removal

of flexible conduit and wiring disconnection from the terminal blocks.

The governor and over-speed protection equipment are shipped loose to be installed in the

customer control room, in most cases. For those cases where they are not shipped loose, both

devices are installed in a skid-edge enclosure with operators mounted on the external enclosure

door allowing for local governor operation when installed in a hazardous location. Wiring can

be removed from the terminal blocks allowing the components to be replaced.

In some cases, where there are RTDs and vibration probes as well as limit switch indicators of

the T&T valve position, there could be enclosures containing terminal blocks. These enclosures

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could be installed on the turbine base on a junction box stand with conduit running from each

electrical device, mounted on the steam turbine, to the enclosure.

Accelerometers are installed externally on the bearing case caps and are readily accessible for

removal and probe cable disassembly and re-assembly.

Tachometers are shipped loose in most cases. They can be easily removed and replaced by

removal of the flex conduit at the union and disconnection of wiring from the terminal blocks.

Pressure and temperature transmitters are typically locally mounted by D-R and wired by the

customer. In cases where there is a skid-mounted enclosure, disconnection and reconnection

from terminal blocks and flex conduit with a union can remove the transmitter wiring.

O.3

Electrical Certification and Standards

The electrical components installed on all SST turbines are selected to satisfy the

specific electrical area classifications indicated/required by the customer. All

wiring is performed to meet current codes of the various countries where the SST

turbines will be operating: NEC

(National Electric Code), IEC

(International

Electric Code), ATEX Low Voltage criteria, ATEX Machinery Directive, CSA

(Canadian Electric Code), CCOE

(Chief Controller of Explosives) in India,

GHOST in Russia among others. If required, the turbines will be wired to satisfy

intrinsically safe (IS) wiring methods as well as providing purged enclosures and

barriers.

Dresser-Rand wiring protection standard for electrical packaging is using conduit.

D-R can provide armored cable and tray for a cost adder.

O.4

Electrical Maintenance

O.4.1

Routine maintenance

It is the customer’s responsibility to carry out the routine maintenance per the

Dresser-Rand maintenance manual.

O.5

Electrical Packaging

O.5.1

How wiring is marked, protective conductor marking

Wiring is marked using electrical schematic drawing component tag numbers with

permanently embossed wire markers of heat shrinkable sleeve slip on type labels at

each end of the wire. If customer tag numbers are required, these labels are

installed on each conductor in addition to the Dresser-Rand label markers. The

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terminal numbers to which the wires are terminated to are always provided on the

wire marker.

See Figure O-1 of a typical electrical schematic showing the wiring marker

information and termination methods. The wire markers are to be used from the

information in the bubbles (D-R standard tag number) as well as customer tag

numbers (located adjacent to D-R tag bubbles) if provided. Customer wiring is

shown as dotted lines.

Figure O-1 Typical Electrical Schematic Tag Numbers for Wire Marking

O.5.2

Control devices labeled

Control devices such as trip valve test pushbuttons and emergency stop buttons are

labeled with descriptive nameplates mounted on the housing of the operator

spelling out their specific function. If the customer has tag numbers, these are

included as a separate label or included in the wording of the label. See Figure O-2

for the detail of the tags indicated on the electrical schematic.

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Figure O-2 Typical Tag Number Labels Attached to Junction Boxes

O.5.3

As built connection boxes and wiring routing

Enclosures are supplied either to be shipped loose or are installed on the turbine

which house the vibration proximitors and temperature monitoring devices with

customer wiring termination access. The Dresser-Rand standard is for 20% spare

terminal blocks to be provided. Weidmuller SAK-4EN terminal blocks are

Dresser-Rand standard.

No splices shall be permitted in any wire of cable and no more than two wires per

terminal shall be used.

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All wiring shall be terminated in centrally located junction boxes. Wiring in the

boxes shall be run and laced together in an orderly fashion with all nylon tie wraps

from where it leaves the conduit bushing to where it connects in the terminal box.

Here is a list of electrical components which have resistance loads and therefore

power consumptive heat can be generated. Calculations are analyzed to insure that

enclosures are selected in a large enough size to dissipate excess heat generated

from housing electrical components.

COMPONENT

WATTAGE

Peak 150 governor

38 Watts

Solenoid dump valves

36 Watts

Tachometer

15 Watts

Magnetic pickup

50 Watts

Electro-pneumatic actuator

5 Watts

TABLE O-1 WATTAGES OF ELECTRICAL COMPONENTS USED ON SST

From this table it is demonstrated that there are minimal thermal loads being added

to the overall thermal contribution from the electrical components used on SST

turbines.

O.5.4

Materials of conduit and how supported

Dresser-Rand’s standard for wiring protection is to use rigid galvanized steel

conduit supported with Unistrut installed on the baseplate, if provided. See figure

O-2 section O.5.9 for a graphic example of conduit routing on a baseplate.

All conduit runs are are to be a minimum of 10” distance from all steam lines and

steam casings, both horizontally and vertically.

Liquidtight (flex conduit) shall be used for connections to all equipment where

adjustments or vibration requires flexible connections. Maximum length of the

Liquidtight is 36”. Internal grounding wires are provided when applicable from the

device to the grounding bar installed inside the junction boxes.

O.5.5

Percentage fill of conduit

All wiring for the SST turbine does not exceed the minimum percentage fill limits

per the sizes of conduit applied.

O.5.6

Procedure to protect wiring when shipped loose

If electrical components are to be shipped loose, the wiring from the turbine to the

component will be coiled up with protective wrapping applied to the coils. The

wiring markers are installed on the wires for determination of connection to the

correct termination point per the electrical schematic and layout drawings

associated with the contract.

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O.5.7

Terminal head drawing

Figure O-3 is of a standard supplied ¾” terminal head which typically are installed

on limit switches, solenoid valves, magnetic pickups and other electrical

components which do not have their own wiring termination protective hardware.

Figure O-3 Standard ¾” Terminal Head

O.5.8

Wiring into J-box

Junction boxes shall be arranged for side or bottom entry only. Top entry is not

allowed. Conduit unions shall be provided to facilitate replacement or removal of

instruments and junction boxes.

Seals are provided for wiring entrance into all enclosures if the hazardous area

classification requires them.

Hubs are installed into the bottom of the enclosure for Dresser-Rand electrical shop

wiring entrance. Customer connections are left for field installation unless

customer requests hub installation at the factory.

Vents and drains are provided in the top and bottom of the enclosures to allow

moisture from condensation to be drained. The drains and vents are specified in

accordance with the level of protection provided with the enclosure.

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Dresser-Rand incorporates Crouse-Hinds and Hoffmann enclosures unless there are

customer requirements for other suppliers. At a minimum the enclosures are 304

Stainless Steel with NEMA 4X ingress protection ratings.

Here is a description of the ATEX-certified (NEXT) Crouse-Hinds enclosure gasketing:

Features include thirteen basic sizes in two standard depths to optimise the

accommodation

rail-mountable

terminals

components.



Fully removable lid, concealed hinges provide 180° opening



Lid fixing, two or three stainless steel captive screws on one side



Lip on upstand increases gasket contact area, ensuring high degree of ingress protection



Internal / external earth stud



40mm wide fixing lugs for assembly on standard frames



Option of 0, 1, 2, 3 or 4 gland plates with earth stud



One piece gasket on lid and gland plates



Padlock hasp available as additional accessory

The retained stainless steel slotted hex bolt fastenings provide a rapid means of

achieving high integrity ingress protection

(IP) of

66 for reliable & rapid

environmental protection. The high integrity

“single piece” sealing gasket for

superior ingress protection

(IP) of

66 and excellent recovery and re-sealing

properties for continuous environmental protection. An integral drainage channel

prevents liquids or other solids contaminates from running in or falling into the

enclosure when the door is opened, and to minimize gasket path contamination. An

integral external & internal feed through brass earth / ground stud assembly enables

rapid and reliable protective earth / ground connection mounted on the side of the

enclosure for ease of access.

Here is a description of a Hoffmann ATEX certified enclosure:



Easy-to-use Type 316 stainless steel quarter-turn door latching



3-mm double-bit insert for security



Slot and through-hole side-mount hanging brackets



Lift-off door hinges



Fabricated from Type 316 stainless steel



Type 316 stainless steel external fasteners



Gray silicone high-temperature gasket on doors and gland plates

Internal/external brass earth/ground provision

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FIGURE O-4 Enclosure Gasketing Details

O.5.9

Wiring routing drawing

In most cases the electrical wiring is in the customer’s scope from the magnetic

pickup termination head, the solenoid valve termination head, the limit switch

termination hardware, and the temperature monitoring device termination head. In

a few cases the turbine is sold with a baseplate and conduit runs from the

termination heads to the baseplate mounted junction boxes. Figure O-5 shows an

example of non-typical conduit routing into baseplate mounted enclosures.

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Figure O-5 Example

of conduit routing, non-typical application

O.5.10

Details of neutral conductor

On the Dresser-Rand electrical schematic the conductor information is provided in

the notes section of the drawing.

O.5.11

Drawing stating markers for terminals and conductors

Dresser-Rand’s standard electrical schematic states the terminal type and

manufacture on the enclosure sheet of the schematic. Conductor data is located in

the notes section of the electrical schematic drawing, providing manufacture and

conductor part number data.

O.5.12

Drawing showing how cover plates are tied into bonding

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On the Dresser-Rand electrical schematic/layout drawings the details of the

enclosure are provided with notes on gounding and bonding of components.

O.5.13

Drawing showing how protective bonding cross-sectional area of

circuit conductors.

Maximum impedance for protective bonding. Details of the circuit conductors are

provided in the notes section of the electrical schematics.

O.5.14

CE listed components are wired per manufacturer’s instructions.

Testing of component wiring per CENELEC EN60204-1 standards and data are

recorded on FAT form.

O.5.15

Prevention of touch voltage

Testing of touch voltage test limits per CENELEC EN60204-1 standards and data

recorded on FAT form.

O.5.16

Electrical shock hazard warning

There are electrical shock hazard warnings attached to the turbine per CENELEC EN60204-1

standards and the verification data is recorded on FAT form that all applicable drawings are

showing correct warning placement.

O.5.17 Peak starting currents and permitted voltage drops.

The electronic governors are capable of riding out minimal electrical supply

disturbances

O.5.18

Confirmation of use of SST electrical components:

Temperature

Electrical components provided by Dresser-Rand are selected for use within the

environmental parameters presented by the customer. The terminal blocks,

Weidmuller SAK-4EN, have a maximum temperature rating of 100C.

Altitude

Electrical components provided by Dresser-Rand are selected for use within the

environmental parameters presented by the customer. The terminal block

creepage and clearance values were calculated for 2000m above sea level.

Containment

Electrical components provided by Dresser-Rand are selected for use within the

environmental parameters presented by the customer.

Ionizing and non-ionizing radiation

Electrical components provided by Dresser-Rand are selected for use within the

environmental parameters presented by the customer.

Vibration

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Electrical components provided by Dresser-Rand are selected for use within the

environmental parameters presented by the customer.

Shock

Electrical components provided by Dresser-Rand are selected for the use in

environmental conditions presented by the customer specifications.

Physical environment

Electrical components provided by Dresser-Rand are selected for the use in

environmental conditions presented by the customer specifications.

Operating conditions

Electrical components provided by Dresser-Rand are selected for the use in

operational conditions presented in the customer specifications.

Voltage ride-through

Electronic governors, electronic overspeed protection, solenoid valves, limit

switches and all other electrical equipment requiring external power will revert

to shelf state in the event of disconnection from the power supply. It is the

customer responsibility to provide backup power supply capabilities if it is

imperative that the turbine stay operational at all times. The Woodward Peak

150, the most common governor used on SST machines, has a ride-through

characteristic of 28 milliseconds for the 24 VDC power source range of 18-32

VDC. Ride-through is 50 milliseconds for a 120 VDC power source range of

90-150 VDC and 4 cycles ride-trhough for 100 VAC power source range of 88-

132 VAC with a frequency range of 47-63 Hz. Input voltage fluctuations within

the acceptable ranges listed above will not affect operation of the Peak 150

control.

Harmonics

The power quality of the electrical power supply is the responsibility of the

customer. It is the customer's responsibility to insure that the supplied electrical

power provided to the steam turbine is absent of power harmonics per the IEC

standards.

Ingress protection

The levels of ingress protection which are spelled out in the customer

specifications will be applied in the equipment installed on the turbine.

Gaskets on Enclosures

The enclosures specified by Dresser-Rand have the proper gasketing seals on the

enclosure doors to meet the customer specifications. See Figure O-4 above for

typical enclosure gasketing standards.

M. Tensile stress in cables

See Figure O-6 below for pull tension in Alpha Xtra Guard

5 cables or

equivalent typically used for wiring of RTDs and speed probes. The pull

tension of the 20 AWG is 298 N/mm2 and the pull tension of the 18 AWG wire

is 302 N/mm2 both well beyond the maximum requirements of 15 N/mm2 per

EN 60204-1:2006.

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Figure O-6 Cable Pull Tension and Capacitance Properties

Types of insulation and documentation Figures O-6 and O-7

Heating effect on conductors

The wiring insulation provided by Dresser-Rand is certified to the highest

temperature rating available. In the notes section of the electrical schematics are

instructions to the electricians to place conduit runs at a minimum of 10” from

steam lines.

Drains

It is a Dresser-Rand standard to install vertical drains on all conduit low points.

Junction box vents and drains are installed as prudent engineering practice.

Potential earth terminal leakage current

O.6

Electrical Testing

Which specific electrical testing is required for each turbine is delineated in the

Inspection and Test Plan (ITP) which is created for each turbine contract. In this

section is information pertaining to the possible tests which could be required.

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O.6.1

Insulation test plan and certification

High potential (hipot) voltage testing with use of an insulation testing device

known as a MegOHM (meggar) resistance tester determines the condition of

insulation of the turbine wiring. Wires can be checked for good isolation between

the parts of a circuit, which helps to guarantee the safety and quality of electrical

circuits. Hipot tests are helpful in finding nicked or crushed insulation, stray wire

strands or braided shielding, conductive or corrosive contaminants around the

conductors, terminal spacing problems, and tolerance errors in IDC cables. All of

these conditions might cause a device to fail.

The Insulation Resistance test is typically done on every cable tested. It is usually

done at 300 to 500 Vdc with 100 to 500 Megahoms resistance. The test is a very

sensitive to contamination in the assembly process. Solder flux, oils, mold release

agents, and skin oil all can cause problems. This test excels at identifying insulation

that will conduct in the presence of moisture.

O.6.2

Functional preliminary testing

Each unit with an electronic governor is subjected to a Functional Acceptance Test

(FAT) . Items checked, signed and dated are:

Dimensions and correct construction of the panels are checked that they conform

to the drawings.

All components and instrumentation are checked for conformity.

Panel hardware is checked that it conforms to drawings.

All AC and DC power inputs are checked for shorts and isolation between

circuits and grounds

Panel is checked for internal grounding circuits.

Circuit breakers are closed and checked for governor and interface wiring.

All AC and DC power inputs to the panel are checked with proper voltage

supplies.

Electronic governor program is checked for accuracy.

All alarm inputs to panels are simulated for proper indication .

All trip modes in control system are simulated for proper indication on panel.

Trip signals are verified.

The balance of control loops are simulated, checking for correct operation,

indication, and outputs.

m. All circuits are checked for continuity.

O.6.3

Functional bonding test data

Testing of bonding per CENELEC EN60204-1 standards and data recorded on FAT

form.

O.6.4

High leakage current test limits and terminal leakage current

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Testing of high leakage current test limits per CENELEC EN60204-1 standards

and data recorded on FAT form.

O.6.5

Analysis and test report documents showing barrier protection

Testing of barrier protection per CENELEC EN60204-1 standards and data

recorded on FAT form.

O.6.6

Documentation on insulation of Wire and Terminal Blocks

Testing of insulation current test limits per CENELEC EN60204-1 standards and

data recorded on FAT form.

Here are some of the details of the Alpha wire which is a standard Dresser-Rand

component. Bend radius is 10X cable diameter, pull tension is 56 pounds

maximum, voltage rating is 300 Volts RMS, capacitance is 26 picofarads per foot

at 1 kHz nominal, ground capacitance is 47 picofarads per foot at 1 kHz nominal.

Inductance is 0.16 micro henries per foot nominal, conductor DCR is 6.4 ohms per

1000 feet at 20 degrees C, nominal, OA shield DCR is 4.5 ohms per 1000 feet at

20 degrees C.

The maximum and minimum temperature rating range of the typically used Alpha

wire is from -80 to 200C. This wiring is used for the actuator, magnetic speed

probes and RTD temperature monitoring and very infrequently is located within

conduit runs which are near the bearing cases and actuator. The steam chest is

typically jacketed with a thermal insulation barrier for protection of surrounding

equipment and personnel. In most cases the customer is providing the wiring to the

actuator terminal head as well as the RTD and magnetic speed probe termination

heads installed on the bearing cases. The temperature levels are much lower than

the inlet temperatures in proximity to the bearing cases.

O.6.7

Documentation showing no residual voltage

Testing of residual voltage test limits per CENELEC EN60204-1 standards and

data recorded on FAT form.

O.6.8

Documentation showing size and location of terminal points, all wire

is copper, PE connections

Dresser-Rand standard electrical schematics show the size and location of terminal

points as well as wire type and manufacture and PE connections.

O.6.9

Test report on SST conductor clearances with each other.

Testing of conductor clearances per CENELEC EN60204-1 standards and data

recorded on FAT form. The values for the conductor clearances and creepage were

calculated from an Extract DIN VDE 0110-04.97. This standard is a technical

adaptation of IEC Report 664/664A. Installation Category II was used, which is

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for equipment intended for use in installations or parts of installations in which no

overvoltages can occur.The clearance calculations were conducted per the

dimensions and characteristics of the Weidmuller SAK-4EN terminal blocks which

are standard offering of D-R. The clearance calculations indicate a maximum of

1.2 mm for these terminal blocks. The clearance between the terminals of the

SAK-4EN terminal blocks is 6.5 mm, more than 5 times the minimum clearance

allowed.

O.6.10

Test report on SST creepage of Conductors

Testing of creepage per CENELEC EN60204-1 standards and data recorded on

FAT form. The creepage calculations were checked per the Weidmuller SAK-4EN

terminal block dimensions. The distances between the conductors minimum

calculated value due to creepage is 1.5 mm which is 1/5 of the 6.5 mm terminal

block distances being used.

O.6.11

Test report on SST mechanical damage caused by short circuits.

Testing of short circuit test limits per CENELEC EN60204-1 standards and data

recorded on FAT form.

O.6.13

Analysis on SST enclosure gasketing construction.

Dresser-Rand incorporates Crouse-Hinds and Hoffmann enclosures unless there are

customer requirements for other suppliers. At a minimum the enclosures are 304

Stainless Steel with NEMA 4X ingress protection ratings.

O.7

Programming of Electrical Devices

O.7.1

Peak 150 programmer and program entry

In the Woodward Peak 150 Installation and Operation manual 85565 complete and

thorough instructions are provided for the programming of the Peak 150 governor.

Dresser-Rand provides a governor program which has the values that are punched

into the governor via the supplied hand held programmer.

O.7.2

Tachometer program entry

Tachtrol 30

For each turbine which has a AI-Tek tachometer, D-R provides programming

parameters on the associated electrical schematic drawing.

Moore

Red Lion

For each turbine which has a Red Lion speed meter, D-R provides

programming parameters on the associated electrical schematic drawing.

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Beka

For each turbine which has a Beka tachometer, D-R provides programming

parameters on the associated electrical schematic drawing.

O.7.3

Valtek Calibration

The electro-pneumatic actuators are calibrated at the Dresser-Rand factory before the

no-load testing of each unit.

O.8

Customer Responsibilities

O.8.1

Power supply disconnect method

Typically the customer is responsible for the design and installation of power

supply disconnect hardware for the electronic governor, electronic over-speed

protection, solenoid valves and other power consuming components mounted on

the turbine. There must be an acceptable disconnect (isolation) at each single

incoming source when required (for example: for work on the machine, including

electrical equipment). When two or more supply disconnecting devices are

provided, protective interlocks for their correct operation shall also be provided in

order to prevent a hazardous situation, including damage to the machine or to the

work in progress.

The supply disconnecting device shall be one of the following types:

A. Switch-disconnector, with or without fuses, in accordance with IEC 60947-3,

utilization category AC-23B or DC-23B

B. Disconnector, with or without fuses, in accordance with IEC 60947-3, that has

an auxiliary contact that in all cases causes the switching devices to break the

load circuit before the opening of the main contacts of the disconnector.

C. A circuit breaker suitable for isolation in accordance with IEC 60947-2

D. Any other switching device in accordance with an IEC product standard for that

device and which meets the isolation requirements of IEC 60947-1 as well as a

utilization category defined in the product standard as appropriate for on-load

switching of motors or other inductive loads

E. A plug/socket combination for a flexible cable supply.

When the supply disconnecting device is one of the types listed in the above

sections A to D, it shall fulfill all of the following requirements:

Isolate the electrical equipment from the supply and have one OFF (isolated) and one

ON position marked with “O” and “I”

(symbols IEC 604178-5008 (DB:2002-10) and

IEC 60417-5007 (DB:2002-10)).

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Have a visible contact gap or a position indicator which cannot indicate OFF (isolated)

until all contacts are actually open and the requirements for the isolating function have

been satisfied.

Have an external operating means (for example—handle), (exception: power-operated

switchgear need not be operable from outside the enclosure where there are other means

to open it). Where the external operating means is not intended for emergency

operations, it is recommended that it be colored BLACK or GRAY.

To be provided with a means permitting it to be locked in the OFF (isolated) position

(for example by padlocks). When so locked, remote as well as local closing shall be

prevented.

Disconnect all live conductors of its power supply circuits. However, for TN supply

systems, the neutral conductor may or may not be disconnected except in countries

where disconnection of the neutral conductor (when used) is compulsory.

Have breaking capacity sufficient to interrupt the current of the largest motor when

stalled together with the sum of the normal running currents of all other motors and/or

loads. The calculated breaking capacity may be reduced by the use of a proven

diversity factor.

When the supply disconnecting device is a plug/socket combination, it shall fulfill

the following requirements:

Have the switching capability, or be interlocked with a switching device that has a

breaking capacity sufficient to interrupt the current of the largest motor when

stalled together with the sum of the normal running currents of all other motors

and/or loads. The calculated breaking capacity may be reduced by the use of a

proven diversity factor. When the interlocked switching device is electrically

operated (for example: a contactor) it shall have an appropriate utilization category.

Where the supply disconnecting device is a plug/socket combination, a switching

device with at appropriate utilization category shall be provided for switching the

machine on and off. This can be achieved by the use of the interlocked switching

device described above.

Operating Means—

The operating means (for example, a handle) of the supply disconnecting device

shall be easily accessible and located between 0.6 m (1.9 ft.) and 1.9 m (6.2 ft.)

above the servicing level. An upper limit of 1.7 (5.6 ft.) is recommended.

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Excepted Circuits—

The following circuits need not be disconnected by the supply disconnecting

device:

Under-voltage protection circuits that are only provided for automatic tripping

in the event of supply failure.

Where such a circuit is not disconnected by the supply disconnecting device:

permanent wiring label(s) in accordance with 16.1 shall be appropriately placed in

proximity to the supply disconnecting device.

Local operation of the supply disconnecting device to effect emergency switching

off shall be readily accessible and should meet the color requirements.

O.8.2

Customer responsibility for emergency stop controls and devices,

location description of emergency devices

It is the customer’s responsibility to provide emergency stop controls and devices

and provide the location description and accessibility of these emergency devices.

Combined start and stop controls. Push-buttons and similar control devices that,

when operated, alternately initiate and stop motion shall only be provided for

functions which cannot result in a hazardous situation.

Use of more than one operator control station. Where a machine has more than one

operator control station, including one or more cable-less control stations, measures

shall be provided to ensure that only one of the control stations can be enabled at a

given time. An indication of which operator control station is in control of the

machine shall be provided at suitable locations as determined by the risk

assessment of the machine.

Devices for emergency stop shall be readily accessible by being located at each

operator control stations and at other locations where the initiation of an emergency

stop can be required.

There can be circumstances where confusion can occur between active and inactive

emergency stop devices caused by disabling the operator control station. In such

cases, means (for example: information for use) shall be provided to minimize

confusion.

Emergency switching off devices shall be located as necessary for the given

application. Normally, those devices will be located separate from operator control

stations. Where it is necessary to provide a control station with an emergency stop

device and an emergency switching off device, means shall be provided to avoid

confusion between these devices.

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Color of actuators. Actuators of emergency switching off devices shall be colored

RED. If a background exists immediately around the actuator, the background

shall be colored YELLOW.

O.8.3

Customer responsibility for earth faults - required accidental start

protection

The customer is responsibility to provide earth fault interrupt equipment and

lockout process and procedure to prevent accidental startup.

Earth faults on any control circuit shall not cause unintentional starting, potentially

hazardous motions, or prevent stopping of the machine.

O.8.4

Customer responsibility for potentiometer rotation stop

The customer is responsible for providing rotation stops on any and all

potentiometer installations.

Devices having a rotational member, such as potentiometers and selector switches,

shall have the means of prevention of rotation of the stationary member. Friction

alone shall not be considered sufficient.

O.8.5

Customer responsibility for stopping by de-energizing

The customer is required to institute controls which will facilitate the turbine

stopping by de-energizing the controls.

O.8.6

Customer responsibility that control circuits are connected to bonding

circuit

The customer is responsible for ensuring the control circuits are connected to the

bonding circuit which is also within the customer’s responsibility.

Protection by automatic disconnection of supply: This measure consists of the

interruption of one or more of the line conductors by the automatic operation of a

protective device in case of a fault. This interruption shall occur within a

sufficiently short time to limit the duration of a touch voltage to a time within

which the touch voltage is not hazardous.

These measures necessitate the coordination between:

a) The type of supply and earthing system.

b) The impedance values of the different elements of the protective bonding

system

c) The characteristics of the protective devices that detect insulation fault(s).

Automatic disconnection of the supply of any circuit affected by an insulation

fault is intended to prevent a hazardous situation resulting from a touch voltage.

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This protective measure comprises both protective bonding of exposed conductive

parts and either:

a) Over-current protective devices for the automatic disconnection of the supply

on detection of an insulation fault in TN systems, or

b) Residual current protective devices to initiate the automatic disconnection of

the supply on detection of an insulation fault from a live part to exposed

conductive parts or to earth in TT systems, or

c) Insulation monitoring or residual current protective devices to initiate automatic

disconnection of IT systems. Except where a protective device is provided to

interrupt the supply in the case of the first earth fault, an insulation monitoring

device shall be provided to indicate the occurrence of a first fault from a live

part to exposed conductive parts or to earth. This insulation monitoring device

shall initiate an audible and/or visual signal which shall continue as long as the

fault persists.

O.8.7

Customer responsibility that battery control station will not cause

hazardous condition

The customer has the responsibility to insure that the battery control station will not

cause any hazardous condition to exist in the SST operation.

Battery-powered operator control stations. A variation in the battery voltage shall

not cause a hazardous situation. If one or more potentially hazardous motions are

controlled using a battery-powered cable-less operator control station, a clear

warning shall be given to the operator when a variation in battery voltage exceeds

specified limits. Under those circumstances, the cableless operator control station

shall remain functional long enough for the operator to put the machine into a non-

hazardous situation.

O.8.8

Customer responsibility for operator control station stop over-ride

precedence

The customer is responsible for instituting the hardware/software to guarantee

operator control station stop over-ride precedence.

O.8.9

Customer responsibility for enabling control requirements

The customer is responsible for enabling control requirements.

Start functions. Start functions shall operate by energizing the relevant circuit.

Enabling control is a manually activated control function interlock that:

a) When activated allows machine operation to be initiated by a separate start

control

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b) When de-activated---

---initiates a stop function and----prevents initiation of machine

operation.

Enabling control shall be so arranged as to minimize the possibility of defeating the

shut-down command, for example: by requiring the de-activation of the enabling

control device before machine operation may be re-initiated. It should not be

possible to defeat the enabling function by simple means.

O.8.10

Customer responsibility that ES (Emergency Stop) shuts off motive

force

The customer is responsible for proper design of the emergency stop controls

which will shut off any and all of the motive force to the turbine.

Emergency stop operations (emergency stop, emergency switching off). Once

active operation of emergency stop or emergency switching off of the actuator has

ceased following a command, the effect of this command shall be sustained until it

is reset. This reset shall be possible only by manual action at that location where

the command has been initiated. The reset of the command shall not restart the

machinery but only permit restarting.

O.8.11

Customer responsibility that resetting of ES requires manual

intervention

The customer has the responsibility to properly incorporate into the turbine controls

that the resetting of the emergency stop components requires manual intervention

for the reset of the turbine controls.

The emergency stop shall function either as a stop category 0 or as a stop category

1. The choice of the stop category of the emergency stop depends on the results of

a risk assessment of the machine.

In addition to the requirements for stop, the emergency stop function has the

following requirements:

a) It shall override all other functions and operations in all modes.

b) Power to machine actuators that can cause a hazardous situation(s) shall be

either removed immediately (stop category 0) or shall be controlled in such a

way to stop the hazardous motion as quickly as possible (stop category 1)

without creating other hazards.

c) Reset shall not initiate a start

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O.8.12

Customer responsbility that any stop function over-rides any start

function

The customer has the responsibility to design and incorporate into the controls the

capability of any and all stop functions to over-ride any and all of the start function

controls.

Stop Function.

a) Stop category 1: A controlled stop with power available to the machine

actuators to achieve the stop and the removal of power when the stop is

achieved.

b) Stop category 2: A controlled stop with power left available to the machine

actuators.

Where more than one control station is provided, stop commands from any control

station shall be effective when required by the risk assessment of the machine.

O.8.13

Customer responsibility to provide over-current protection

It is the customer’s responsibility to properly design, install, and maintain over-

current protection equipment. The measures to be taken to protect the equipment

against the effects of over-current arising are from a short circuit, abnormal

temperature, loss of or reduction in the supply voltage, earth fault/residual current,

and over-voltage due to lighting and switching surges. General over-current

protection shall be provided where the current in a machine circuit can exceed

either the rating of any component of the current carrying capacity of the

conductors, whichever is the lesser value.

Supply conductors. Unless otherwise specified by the user, the supplier of the

electrical equipment is not responsible for providing the over current protective

device for the supply conductors to the electrical equipment Dresser-Rand states on

the P&I list the data necessary for selecting the over current protective device.

Power circuits. Devices for detection and interruption of over current shall be

applied to each live conductor.

The following conductors, as applicable, shall not be disconnected without

disconnecting all associated live conductors:

a) Neutral conductor of AC power circuits

b) The earthed conductor of DC power circuits

c) DC power conductors bonded to exposed conductive parts of mobile machines

Control circuits. Conductors of control circuits directly connected to the supply

voltage and of circuits supplying control circuit transformers shall be protected

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against over-current. Conductors of control circuits supplied by a control circuit

transformer or DC supply shall be protected against over-current:

a) In control circuits connected to the protective bonding circuit, by inserting an

over-current protective device into the switched conductor.

b) In control circuits not connected to the protective bonding circuit.

c) Where the same cross sectional area conductors are used in all control circuits,

by inserting an over-current protective device into the switched conductor.

d) Where different cross-sectional areas conductors are used in different sub-

circuits, by inserting an over-current protective device into both switched and

common conductors of each sub-circuit.

Lighting circuits. All unearthed conductors of circuits supplying lighting shall be

protected against the effects of short circuits by the provision of over-current

devices separate from those protecting other circuits.

O.8.14

Customer responsibility that start functions shall operate by

energizing relevant circuit

The customer’s responsibility is to insure that the start functions shall operate by

energizing the specific circuit which starts the turbine.

In the case of machines requiring the use of more than one control station to initiate

a start, each of these control stations shall have a separate manually actuated start

control device. The conditions to initiate a start shall be:

a) All required conditions for machine operation shall be met.

b) All start control devices shall be in the released (off) position.

c) All start control devices shall be actuated concurrently.

O.8.15

Customer is responsible for DC power supplies

The customer is responsible for the proper sizing, installation and maintenance of

DC power supplies.

O.8.16

Customer is responsible for protective bonding circuit

The customer is responsible for the proper installation and maintenance of

protective bonding circuitry.

Dresser-Rand, when the contract requires it, provides bonding/grounding lugs on

the sole-plates, gauge-boards, and base-plates as shown in figures O-7 through O-9.

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Figure O-8 Grounding lug (008) on gaugeboard

Figure O-9 Grounding lug (007) on soleplate

Equi-potential bonding. Normally functional grounding is achieved by connection

to the protective bonding circuit. But where the level of electrical disturbances on

the protective bonding circuit is not sufficiently low for proper functioning of

electrical equipment, it may be necessary to connect the functional bonding circuit

to a separate functional earthing conductor.

Protective bonding circuit. The protective bonding circuit consists of PE

terminal(s). All parts of the protective bonding circuit shall be so designed that

they are capable of withstanding the highest thermal and mechanical stresses that

can be caused by the earth-fault currents that could flow in that part of the

protective bonding circuit. Where the conductance of structural parts of the

electrical equipment or of the machine is less than that of the smallest protective

conductor connected to the exposed conductive parts, a supplementary bonding

conductor shall be provided. This supplementary bonding conductor shall have a

cross-sectional area not less than half that of the corresponding protective

conductor.

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If an IT distribution system is used, the machine structure shall be part of the

protective bonding cirduit and insulation monitoring shall be provided.

Protective conductors. Copper conductors are preferred. Where a conductor

material other than copper is used, its electrical resistance per unit length shall not

exceed that of allowable copper conductor and such conductors shall be not less

than 16 square mm in cross-sectional area.

The cross-sectional area of protective conductors. This requirement is met in most

cases where the relationship between the cross-sectional area of the phase

conductors associated with that part of the equipment and the cross-sectional area

of the associated protective conductor is in accordance with Table 1.

Continuity of the protective bonding circuit. All exposed conductive parts shall be

connected to the protective bonding circuit.

Exclusion of switching devices from the protective bonding circuit. The protective

bonding circuit shall not incorporate a switching device or an over-current

protective device (for example, switch or fuse). No means of interruption of the

protective grounding conductor shall be provided. Exception: Links for test or

measurement purposes that cannot be opened without the use of a tool and that are

located in an enclosed electrical operating area. Where the continuity of the

protective bonding circuit can be interrupted by means of removable current

collectors or plug/socket combinations, the protective bonding circuit shall be

interrupted by a first-make last-break contact.

Protective conductor connecting points. The protective conductor connecting

points shall have no other function and are not intended, for example, to attach or

connect appliances or parts. Each protective conductor connecting point shall be

marked or labeled as such using the symbol IEC 60417-5019 (DB:2002-10), or

with letters PE, the graphical symbol being preferred, or by use of the bi-color

combination GREEN-AND-YELLOW, or any combination of these.

Functional bonding. Protection against mal-operation as a result of insulation

failures can be achieved by connecting to a common conductor.

Measures to limit effects of high leakage current. The effects of high leakage

current can be restricted to the equipment having high leakage current by

connection of that equipment to a dedicated supply transformer having separate

windings. The protective bonding circuit shall be connected to exposed conductive

parts of the equipment and, in addition, to the secondary winding of the

transformer.

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Control circuits supply. Where control circuits are supplied from an AC source, a

control transformer shall be used for supplying the control circuits. Such

transformer shall have separate windings.

Where DC control circuits derived from an AC supply are connected to the

protective bonding circuit, they shall be supplied from a separate winding of the

AC control circuit transformer or by another control circuit transformer.

O.8.17

Customer is responsible for over-voltage suppression

(lightning

arrestors)

The customer is responsible for the proper installation and maintenance of over-

voltage surge protection (lightning arrestors).

Protection against over-voltages due to lightning and to switching surges.

Protective devices can be provided to protect against effects of over-voltages due to

lightning or to switching surges where provided:

Devices for the suppression of over-voltages due to lightning shall be

connected to the incoming terminals of the supply disconnecting device.

Devices for the suppression of over-voltages due to switching surges shall be

connected across the terminals of all equipment requiring such protection.

O.8.18

Customer is responsible for transformer over-current protection.

The customer is responsible for all transformer over-current protection devices to

be installed properly and maintained.

Transformers shall be protected against over-current in accordance with the

manufacturer instructions. Such protection shall also avoid nuisance tripping due

to transformer magnetizing inrush currents. The type and setting of the over-

current protective device should be in accordance with the recommendations of the

transformer supplier.

O.8.19

Customer is responsible for certifications

The customer is responsible for maintaining the certification documentation

required for customer ATEX/EU compliance.

O.8.20

Customer is responsible for accidental disabling of electricity to

SST turbine

The customer is responsible for proper design and installation of equipment to

prevent accidental power interruption to the SST turbine.

Protection against supply interruption or voltage reduction and subsequent

restoration. These conditions can cause a hazardous situation, damage to the

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machine or to work in progress. Under-voltage protection shall be provided by, for

example, switching off the machine at a pre-determined voltage level. Upon

restoration of the voltage or upon switching on the incoming supply, automatic or

unexpected restarting of the machine shall be prevented where such a restart can

cause a hazardous situation.

O.8.21

Customer is responsible for prevention of unwanted startup

It is the customer’s responsibility to design, install, and incorporate lockout

hardware and procedures to prevent unwanted turbine startup.

Devices for switching off for the prevention of unexpected startup (for example:

where, during maintenance, a start-up of the machine or part of the machine can

create a hazard).

Such device shall be appropriate and convenient for the intended use, shall be

suitable placed, and readily identifiable as to their function and purpose

(for

example: by a durable marking in accordance with 16.1 where necessary).

Means shall be provided to prevent inadvertent and/or mistaken closure of these

devices either at the controller or from other locations. Devices that do not fulfil

the isolation function (for example, a contactor switched off by a control circuit)

may only be provided where intended to be used for situations that include:

a) Inspections

b) Adjustment

O.8.22

Customer is responsible for locking of emergency off isolation

operators

It is the customer’s responsibility to incorporate locking out of emergency shut-

down isolator hardware.

Emergency switching off should be provided where there is the possibility of other

hazards or damage caused by electricity.

Emergency switching off is accomplished by switching off the relevant incoming

supply by electromechanical switching devices, effecting a stop category 0 of

machine actuators connected to this incoming supply. When a machine cannot

tolerate this stop category 0 stop, it may be necessary to provide other measures,

for example: protection against direct contact, so that emergency switching off is

not necessary.

O.8.23

It is the customer responsibility to ensure that there is not a

connection between the neutral conductor and the protective bonding

circuit

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According to CENELEC EN60204-1 it is the customer responsibility to insure that

there is not a connection between the neutral conductor and the protective bonding

circuit.

There shall be no connection between the neutral conductor and the protective

bonding circuit inside the electrical equipment nor shall a combined PEN terminal

be provided. Exception: a connection may be made between neutral terminal and

the PE terminal at the point of the connection of the power supply to the machine

for TN-C systems.

O.8.24

It is the customer responsibility to guarantee that the electrical

components on the SST turbine are connected to a single incoming

power source.

A single point connection for the turbine power must be provided by the customer

that meets the parameters outlined in this chapter.

Incoming supply conductor terminations: It is recommended that, where

practicable, the electrical equipment of a machine is connected to a single incoming

supply. Where another supply is necessary for certain parts of the equipment (for

example, electronic equipment that operates at a different voltage), that supply

should be derived, as far as is practicable, from devices (for example, transformers,

converters) forming part of the electrical equipment of the machine.

O.8.25

Power supply testing is the responsibility of the customer.

The customer is responsible for the power supply testing per the requirements of

CENELEC EN60204-1.

The connection of the power supply and of the incoming external protective

conductor the the PE terminal of the machine, shall be verified by inspection. The

conditions for the protection by automatic disconnection of supply shall be verified

by both:

1) Verification of the fault loop impedance by

a) Calculation

b) Measurement

2) Confirmation that the setting and characteristics of the associated over-current

protective device are correct.

Functional tests. The function of electrical equipment shall be tested. The function

of circuit for electrical safety (for example: earth fault detection) shall be tested by

the manufacturer.

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Re-testing. Where a portion of the machine and its associated equipment is

changed or modified, that portion shall be re-verified and re-tested as appropriate.

This re-testing is the responsibility of the customer.

O.8.26

Power quality customer requirements.

The customer is required by the IEC low voltage directive EN60204-1 to provide

power to the electrical load of supplied devices with harmonic distortion not

exceeding 10% of the total r.m.s. voltage between live conductors for the sum of

the 2^nd through to the 5^th harmonic. An additional 2% of the total r.m.s. voltage

between live conductors for the sum of the 6^th through to the 30^th harmonic is

permissible.

O.8.27

Customer responsibility for protection from electric shock.

The customer is responsible for the wiring and connection of electrical components

and equipment of electrical components which is in their scope (any wiring and

installation of equipment not installed and wired by Dresser-Rand) per the

component manufacturer instructions.

The electrical equipment shall provide protection of persons against electric shock

from:

a) Direct contact

b) Indirect contact

O.8.28

Customer responsible for abnormal temperature protection.

Resistance heating or other circuits that are capable of attaining or causing

abnormal temperatures (for example, due to short-time rating or loss of cooling

medium) and therefore can cause a hazardous situation shall be provided with

suitable detection to initiate an appropriate control response.

O.8.29

Customer responsible for motor over-speed protection.

The over-speed protection of auxiliary motors, such as lube oil pump motors,

which are in the customers’ scope of supply, are the responsibility of the customer

to provide over-speed protection controls.

O.8.30

Customer responsibility for operation and minimizing risks.

Where a machine has more than one control station, measures shall be provided to

ensure that the initiation of commands from different control stations do not lead to

a hazardous situation.

Control functions in the event of failure. Where failures or disturbances in the

electrical equipment can cause a hazardous situation or damage to the machine or

to the work in progress, appropriate measures shall be taken to minimize the

probability of the occurrence of such failures or disturbances. The required

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measures and the extent to which they are implemented, either individually or in

combination, depend on the level of risk associated with the respective application.

The electrical control circuits shall have an appropriate level of safety performance

that has been determined from the risk assessment at the machine. The

requirements of IEC 60261 and/or 13849-1:1999, ISO 13849-2:2003 shall apply.

Measures to reduce those risks include but are not limited to:

a) Use of proven circuit techniques and components

b) Provision of partial or complete redundancy or diversity

c) Provision for functional tests

Measures to minimize risk in the event of failure - Use of proven circuit techniques

and components.

These measures include but are not limited to:

a) Bonding of control circuits to the protective bonding circuit for functional

purposes.

b) Connection of control devices 1

c) Stopping by de-energizing

d) Switching devices having direct opening action (see IEC 60947-5-1)

O.8.31

Physical separation or grouping (11.2.2) customer responsibility.

Control devices mounted in the same location and connected to the supply voltage,

or to both supply and control voltages, shall be grouped separately from those

connected only to the control voltages.

Terminals shall be separated into groups for:

a) Power circuits

b) Associated control circuits

c) Other control circuits, fed from external sources (for example: for interlocking)

The groups may be mounted adjacently, provided that each group can be readily

identified

(for example: by markings, by the use of different sizes, by use of

barriers or by colors). When arranging the location of devices

(including

interconnections), the clearances and creepage distances specified for them by the

supplier shall be maintained, taking into account the external influences or

conditions of the physical environment.

O.8.32

Customer responsibility for prevention of indirect contact

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For each circuit or part of the electrical equipment, at least one of the measures

shall be applied:

a) Measure to prevent the occurrence of a touch voltage or

b) Automatic disconnection or the supply before the time of contact with a touch

voltage can become hazardous

Prevention of the occurrence of a touch voltage. Measures to prevent the

occurrence of a touch voltage include the following:

a) Provision of class II equipment by equipment insulation

b) Electrical separation

Protection by provision of class II equipment or by equivalent insulation. This

measure is intended to prevent the occurrence of touch voltage on the accessible

parts through a fault in the basic insulation. This protection is covered by one of

the following:

a) Class II electrical devices or apparatus (double insulation, reinforced insulation

or by equivalent insulation in accordance with IEC 61140)

b) Switch-gear and control-gear assemblies having total insulation in accordance

with IEC 60439-1

c) Supplementary or reinforced insulation in accordance with 413.2 of IEC 60364-

4-41

Protection by electrical separation of an individual circuit is intended to prevent a

touch voltage through contact with exposed conductive parts that can be energized

by a fault in the basic insulation of the live parts of that circuit. For this type of

protection, the requirements of 413.3.5 of IEC 60364-4-41 apply.

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