Turbine-Over-Hauling-Procedure - Siemens - Recommends Birkosit

Siemens, Wesel, Germany
NG90/81/45-4IZ
S.Rameshkumar Mechanical Maintenance +WK80/90/0-3RHP
Turb+SA21LP Turb

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TURBINE OVERHAULING
Scope of Work

INDEX
1.0 Work Related Documents :
1.1 List of drawings.
1.2 Turbine Service Manual – Siemens Ref : ESO/0689/86-05-13/KWU/la-mg.

2.0 Preparation for Inspection.

3.0 Alignment Checks :
3.1 Open Bearing pedestal.
3.2 Uncouple main oil pump.
3.3 Uncouple Generator.
3.4 Uncouple LP rotor.
3.5 Check alignment between the Main Oil Pump and the HP Turbine.
3.6 Check alignment between the HP Turbine and the LP Turbine.
3.7 Check alignment between the Generator and the LP Turbine.
3.8 Check internal alignment of the LP Turbine.
3.9 Check internal alignment of the HP Turbine.

4.0 Disassembly :
4.1 HP Turbine.
4.2 LP Turbine.
4.3 Valve blocks.
4.4 Lube oil system.

5.0 Non-Destructive Testing.

6.0 Fact-Finding :
6.1 Components, Parts and Individual areas to be inspected.
6.2 Component / Part findings checklist.
6.3 List of Fact-Finding Tools, instruments and accessories.
6.4 List of potential findings.

7.0 Reassembly :
7.1 LP Turbine.
7.2 HP Turbine.
7.3 Valve blocks.
7.4 Alignment checks.
7.5 Lube oil system.

8.0 Commissioning :

T-OH-procedure F.K. 24 November 2006

Turbine Overhauling - Scope of Work
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2.0 PREPARATIONS FOR INSPECTION :
♦ Evaluate latest operating records and related data.
♦ Check for availability of spare parts.
♦ Perform functional inspection of modular units.
♦ Perform leak checks in the form of visual and tactile inspections.
♦ Check shaft-line grounding.
♦ Check turbine-generator running behavior prior to shutdown; perform vibration measurements.
♦ Set up jobsite; ready all scaffolding, tools etc.
♦ Measure vacuum reduction rate.
♦ Shutdown the system.
♦ Cool turbine-generator via turning gear operation.
♦ Disconnect oil pumps, with the exception of the lift-oil pump.
♦ Remove turbine enclosure.
♦ Remove insulation.
♦ Remove vibration pickups.
♦ Protect ends of cables against damage.

General Recommendations :
♦ Use only “Silicon-free” lubricants on the oil side.
♦ Observe all relevant accident prevention regulations.
♦ Observe all relevant fire prevention regulations.
♦ Exercise caution in the handling of cleaning agents and acids (Wear protective clothing).
♦ Observe manufacturer’s parts identification system at each step of assembly/disassembly.
♦ The following sealants are recommended :
♦ For the steam side : Birkosit.
♦ For the oil side : Hylomar.
♦ The followings lubricant is recommended : Gleitmo 160

T-OH-procedure {F.K.} 24 November 2006

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3.0 ALIGNMENT CHECKS :

3.1 Open Bearing Pedestal :
Procedure :
♦ Record pedestal position indicator readings on the HP Turbine (Z 37, Z 38; View VI, Section U1-
U1) and LP Turbine (Z 58, Z 60; Detail V4).
♦ Record rotor position indicator readings on the LP turbine (Z 72; Part 3).
♦ Remove top of rear bearing pedestal (Z 22)
♦ Remove seal rings from the top and bottom halves of the bearing pedestal.
♦ Remove center top-half bearing pedestal (Z 15).
♦ Dismantle and store piping from the front top-half bearing pedestal.
♦ Remove front top-half bearing pedestal (Z 1).
♦ Remove top-half thrust bearing (Z 3).
♦ Remove thermocouples (Z 7) from the top and bottom halves.
♦ Check and record the rotor position in the bottom-half thrust bearing.
♦ Measure and record the alignment dimensions of the HP and LP turbines (cf. assembly data sheet).
♦ Remove bottom-half thrust bearing.
♦ Measure and record axial movement of the shaft line (cf. assembly data sheet).
♦ Reassemble bottom-half thrust bearing

3.2 Uncoupling Main Oil Pump :
Procedure :
♦ Remove hall generators (Z 14)
♦ Remove enclosure (Z 10; part 60, 65)
♦ Check identification markings on the coupling parts (part 100)
♦ Remove centerpiece of sleeve.
♦ Remove circlip
♦ Pull both sleeve sections off of the hubs.


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Evaluation :
♦ Teeth.
♦ Clean couplings parts, protect against corrosion and store.

3.3 Uncoupling Generator :
Procedure :
♦ Check identification markings on the coupling flanges, bolts and nuts (Z 72.1)
♦ remove coupling nuts.
♦ Remove coupling bolts.
♦ Clean coupling nuts and bolts, protect against corrosion, and store.
♦ Turn jack screws in up to contact face.
♦ Continue turning the jack screws to push apart the coupling flange.
♦ Push the generator rotor up to stop in the positive direction.

3.4 Uncoupling L. P. rotor :
Procedure :
♦ Position the lifting fixture (Z 21)
♦ Provide metal strips for the support bearing.
♦ Check the identification markings on the coupling flange, bolts and nuts (Z 72).
♦ Remove coupling nuts.
♦ Turn jack screws in up to the contact face.
♦ Continue turning jack screws to press the two halves of the coupling flange apart by 3mm.
♦ Hand-tighten the coupling nuts.

3.5 Check Alignment between the Main Oil Pump and the HP Turbine
Procedure :
♦ Attach measuring instrument.
♦ Check and record the alignment between the pump shaft and the turbine rotor.

3.6 Check alignment between the HP Turbine and the LP Turbine
Procedure :
♦ Check and record the alignment between the HP rotor and the LP rotor.


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3.7 Check alignment between the Generator and the LP Turbine
Procedure :
♦ Check and record the alignment between the LP rotor and the Generator.

3.8 Check internal alignment of the LP Turbine
Procedure :
♦ Measure and record the exact values at the rear bearing pedestal measuring points (Z 22).
♦ Measure and record the exact values at the outer-casing circumferential profile measuring points.
♦ Check for full contact between the pedestal s upport brackets and the base plate (Z 85, 59, 60;
Sections F2-F2, F4-F4).
♦ Remove coupling nuts (Z 72).
♦ Remove coupling bolts.
♦ Clean coupling nuts and bolts, protect against corrosion, and store.
♦ Use lifting fixture to support weight of rotor (Z 21).
♦ Press coupling flange apart by turning in the jack screws.
♦ Push rotor in the positive direction up to 1.0mm ahead of the stop.
♦ Install support bearing, take load off of and remove the lifting fixture.
♦ Mount rear top-half bearing pedestal.

3.9 Check internal alignment of HP Turbine
Procedure :
♦ Measure and record dimension “L” (assembly data sheet) on the front support bracket seats.
♦ Measure and record the exact values at the front and center bearing pedestal m easuring points (Z
71, 1, 15).
♦ Measure and record the exact values at the outer-casing circumferential profile measuring points.
♦ Check for full contact between the rear support brackets and the base plate (Z 37, 39; Section P3-
P3).
♦ Mount the center and front top-half bearing pedestals.
♦ Disconnect the lift-oil pumps.

4.0 DISASSEMBLY :


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4.1 HP Turbine

Open Outer Casing
Procedure :
♦ Disconnect flange joints of upper steam inlet pipes; support weight of pipes as necessary.
♦ Dismantle the upper cross-around piping, incl. swing disk valves; plug openings, store piping,
protect valves against corrosion and store.
♦ Remove and store wall temperature sensor (Z 36)
♦ Ream out (clean) taper-pin bores (Z 26, Part 14)
♦ Bring shoulder bolts into contact with the auxilia ry support brackets (Z 38, Section P1-P1, Part
30).
♦ Remove spacer bolts, washers and disk springs from the front support bracket seat (Z 38, Section
P1-P1, Parts 39-43).
♦ Insert one each additional washer between the spacer bolts and existing washers, and retighten the
spacer bolts.
♦ Loosen joints bolts as per specification.
♦ Clean and screw in guide bolts.
♦ Clean jack screws; apply lubricant to the threads; screw in.
♦ Hitch up the top-half outer casing horizontally onto the proper lifting bosses.
♦ Turn in the jack screws to uniformly lift the top half outer casing by approx. 30 mm.
♦ Lift off top-half outer casing.

Evaluation :
♦ Joint faces, guides, support brackets seat, spherical washers, L-rings.
♦ Protect top-half outer casing against corrosion and store.
♦ Protect spherical washers, spacer bolts, washers and disk springs (Z 38; Section P1-P1, Parts 39-
43) against corrosion and store.
♦ Remove upper spherical washers from the stationary blading carrier (Z 45; Section K1-K3, Part 7)
and inner seal ring (Z 37; Section K-K, Part 287); protect against corrosion and store.
♦ Remove joint bolts from the bottom-half outer casing.

Open Stationary Blade Carrier
Procedure :
♦ Sequence items 500, 525, 550 (Z 42).


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♦ Remove spot welds from the joint bolt nuts.
♦ Ream out (clean) taper-pin bores.
♦ Clean jack screws, apply lubricant to threads; screw in
♦ Hitch up top-half stationary blade carrier, thereby maintaining a horizontal position.
♦ Turn in jack screws to lift top-half by about 30mm.
♦ Lift off stationary blade carrier.

Evaluation :
♦ Joint face, blades, seal strips, spherical washers.
♦ Protect top-half stationary blade carrier against corrosion and store.

Open Inner Casing
Procedure :
♦ Remove and store pressure-instrument lines (Z 40, Part 391).
♦ Remove spot welds from the joint nut bolts.
♦ Clean and thread-in the guide bolts.
♦ Unscrew joint bolts as specified.
♦ Clean jack screws; apply lubricant to threads; screw in.
♦ Hitch up top-half inner casing, thereby maintaining a horizontal position.
♦ Turn in jack screws to lift top half by about 30mm.
♦ Lift off top-half inner casing.
♦ Remove spot welds from the joint bolts of the gland busing (Z 30).
♦ Unscrew joint bolts as specified.
♦ Lift off top-half gland bushing.

Evaluation :
♦ Joint faces, blades, seal strips, L-rings.
♦ Protect inner casing against corrosion and store.

Open Inner Gland Bushing :
Procedure :
♦ Ream out (clean) taper pin bores.


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♦ Unscrew joint bolts.

Evaluation :
♦ Joint face, seal strips.
♦ Protect top-half gland bushing against corrosion and store.

Open and remove Outer Gland Bushing :
Procedure :
♦ Dismantle gland steam line.
♦ Swing out and lift off bottom-half gland bushing.

Evaluation :
♦ Joint face, seal strips.
♦ Protect gland bushings against corrosion and store.

Dismantle Main Oil Pump and Speed Transducer
Procedure :
♦ Detach oil lines from the main oil pump (Z 8)
♦ Remove taper pins and bolts (Z 38, Section Y1-Y1).
♦ Lift off main oil pump; remove spherical washers.
♦ Dismantle main oil pump.

Evaluation :
♦ Impeller, shaft, bearing, spherical washers.
♦ Clean all parts, protect against corrosion and store.
♦ Pull off turbine-end coupling hub (Z 10, Part 100).
♦ Dismantle speed transducer (Z9, 10, 11)

Evaluation :
♦ Coupling, governor impeller, auxiliary parts.
♦ Clean all parts, protect against corrosion and store.


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Remove Rotor
Procedure :
♦ Lift off front top-half bearing pedestal and store.
♦ Remove top-half journal bearing.
♦ Remove thrust bearing.
♦ Lift off and store rear top-half bearing pedestal.
♦ Suspend rotor horizontally at the points marked with U and Y (Z 46) and lift away.
♦ Dismantle overspeed trip device (Z 49).

Evaluation :
♦ Blades, seal strips, shaft journal, auxiliary parts, overspeed trip device.
♦ Reinstall overspeed trip device (Z 49)
♦ Protect rotor against corrosion and store.
♦ Remove bottom-half journal bearing, including the thermocouples (Z 7)

Evaluation :
♦ Journal and thrust bearings.
♦ Protect journal and thrust bearings against corrosion and store.

Remove Bottom-Half Inner Casing
Procedure :
♦ Remove thermocouples to facilitate extraction of the inner casing (Z 40).
♦ Suspend bottom-half inner casing horizontally and lift off.

Evaluation :
♦ Joint face, blades, seal strips, L-rings, guides.
♦ Protect bottom-half inner casing against corrosion and store.
♦ Remove and store bottom-half gland bushing (Z 30).

Remove Bottom-Half Stationary Blade Carrier
Procedure :
♦ Sequence : items 550, 525, 500 (Z 42).
♦ Suspend bottom-half stationary blade carrier in horizontal position and lift off.


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Evaluation :
♦ Joint face, blades, seal strips, spherical washers, guides.
♦ Protect bottom-half stationary blade carrier against corrosion and store.
♦ Remove lower spherical washers (Z 45, Section K1-K3, Part 7), protect against corrosion and
store.

Remove Bottom-Half Inner Gland Bushing
Procedure :
♦ Suspend bottom-half gland bushing in horizontal position and lift off.

Evaluation :
♦ Joint face, seal strips, spherical washers, guides.
♦ Protect bottom-half gland bushing against corrosion and store.
♦ Remove lower spherical washers (Z 37, Secti on K-K, Part 287), protect against corrosion and
store.

Remove Front Bearing Pedestal
Procedure :
♦ Dismantle piping and store.
♦ Remove spot welds from the guides (Z 38, Detail T1 and Section M1-M1).
♦ Unscrew axial guide nuts (Z 38, Detail T1); turn stud bolts (Part 60) from the outer casing;
protect stud bolts and nuts against corrosion and store.
♦ Remove lock bolts and washers from the axial gui de (Z 38, Section M1-M1), unscrew calottes
(Part 22) and remove spherical washers.
♦ Unscrew spacer bolts (Z 37, 38; Section 01-01, Part 16), remove brackets (Part 15).
♦ Suspend bearing pedestal in horizontal position and lift off.

Evaluation :
♦ Slide surfaces, spherical washers.
♦ Protect bearing pedestal against corrosion and store.
♦ Protect hardware against corrosion and store.


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Remove Center Bearing Pedestal
Procedure :
♦ Dismantle and store piping.
♦ Remove spot welds from the axial guide (Z 37, 39; Section M3-M3).
♦ Remove lock bolts and washers, unscrews calottes (Part 122) and extract spherical washers).
♦ Remove screw lock device (Z 37, 39; Section 03-03, Part 115) and loosen bolts (Part 116)
♦ Suspend bearing pedestal in horizontal position and lift off.

Evaluation :
♦ Protect bearing pedestal against corrosion and store.

Remove Axial Casing Guides :
Procedure :
♦ Remove spot welds from the guides Z 37, 38, 39; Sections W1-W1 and W3-W3).
♦ Remove lock bolts and washers; unscrew calottes; extract spherical washers.

Evaluation :

4.2 L. P. Turbine

Open Outer Casing
Procedure :
♦ Dismantle protective liners and rupture disks (Z 57)
♦ Ream out (clean) taper-pin bores (Z 50, Sections L-L and M-M)
♦ Put one each additional washer between the spacer bolts and existing washers (Z 58, 59, 60);
Sections F2-F2 and F4-F4) and tighten the spacer bolts.


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♦ Clean and thread-in the assembly guides.
♦ Clean the jack screws; apply lubricant to threads; turn in jack screws.
♦ Suspend top-half outer casing horizontally from the intended lifting bosses.
♦ Turn in the jack screws to uniformly lift the top-half outer casing by about 30mm
♦ Lift off top-half outer casing.

Evaluation :
♦ Joint face, guides, spherical washers, L-rings.
♦ Protect top-half outer casing from corrosion and store.
♦ Remove upper spherical washers from the stationary blade carrier (Z 58, 59, 60) and inner casing
(Z 58, Section A-A), protect against corrosion and store.
♦ Remove joint bolts from the bottom-half outer casing.

Open Stationary Blade Carrier
Procedure :
♦ Sequence : arbitrary.
♦ Clean and thread-in the guide bolts.
♦ Remove joint bolts.
♦ Clean jack screws; apply lubricant to threads; screw in.
♦ Suspend top-half stationary blade carrier in a horizontal position.
♦ Turn in jack screws to lift top half by about 30 mm.
♦ Lift off top-half stationary blade carrier.

Evaluation :
♦ Joint face, blades, seal strips, spherical washers.
♦ Protect top-half stationary blade carrier against corrosion and store.

Open Inner Casing :
Procedure :
♦ Dismantle and store the pressure-instrument lines (Z 58, Part 391)


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♦ Clean and thread-in guide bolts.
♦ Remove joint bolts.
♦ Clean jack screws; apply lubricant to the threads; screw in.
♦ Suspend top-half inner casing in a horizontal position.
♦ Turn in jack screws to lift the top-half by about 30 mm
♦ Lift off top-half inner casing.

Evaluation :
♦ Joint face, blades, seal strips, L-rings.
♦ Protect top-half inner casing against corrosion and store.

Open and remove Gland Bushings :
Procedure :
♦ Dismantle gland-steam line.
♦ Swing out and lift off bottom-half gland bushing.

Evaluation :
♦ Joint faces, seal strips.
♦ Protect gland bushings against corrosion and store.

Remove Rotor
Procedure :
♦ Lift off and store rear top-half bearing pedestal.
♦ Remove top-half rear journal bearing.
♦ Suspend rotor in the vicinity of the coupling flanges (Z 65) and raise in a horizontal position.

Evaluation :
♦ Blades, seal strips, shaft journal.
♦ Protect rotor against corrosion and store.


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♦ Remove bottom-half journal bearing, including thermocouples (Z 7).

Evaluation :
♦ Journal bearing.
♦ Protect journal bearing against corrosion and stores.

Remove Bottom Half Inner Casing
Procedure :
♦ Suspend bottom-half inner casing in horizontal position and lift-off.
Evaluation :
♦ Joint faces, blades, seal strips, spherical washers, L-rings, guides.
♦ Protect bottom-half inner casing against corrosion and store.
♦ Remove lower spherical washers (Z 58, Section A-A), protect against corrosion and store.

Remove Bottom-Half Stationary Blade Carrier
Procedure :
♦ Sequence : arbitrary.
♦ Suspend bottom-half stationary blade carrier in a horizontal position and lift-off.

Evaluation :
♦ Joint faces, blades, seal strips, spherical washers, guides.
♦ Protect bottom-half stationary blade carrier against corrosion and store.
♦ Remove lower spherical washers (Z 58, 59, 60), protect against corrosion and store.

4.3 Valve Blocks :

Dismantle Emergency Stop Valves
Procedure :
♦ Oil side :
♦ Remove lift indicator
♦ Remove and store ESV piping.
♦ Unscrew nuts of the bolts connecting the oil side and steam side; uniform ly loosen the
tension-rod nuts, thereby relaxing the springs.
♦ Remove oil-side assembly (Z 78, Part 2), in cl. spring and spring retaining plate; rem ove
spring retaining plate, springs and piston (Part 13).


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♦ Unscrew stem connection, remove piston plate (Part 12).
♦ Remove cover and extract actuation piston (Part 14).

Evaluation :
♦ All dismantled parts, body.
♦ Clean all parts and protect against corrosion.

♦ Steam Side :
♦ Unscrew nuts on the mating flange and remove valve (Part 1)
♦ Remove valve seat (Part 10).
♦ Remove valve stem (Part 30) and valve cone (Part 11).

Evaluation :
♦ All dismantled parts, body.

Dismantle Control Valve
Procedure :
♦ Check identification markings on all parts.
♦ Remove valve-lift monitor (Z 80).
♦ Remove and store complete control cylinder (Z 87).
♦ Remove lever (Part 46).
♦ Relax compression springs (Part 36) by unscrewing the top nuts (Part 40).
♦ Remove compression springs and the top and bottom springs retaining plates.
♦ Remove the taper pins (Part 19) and extract the drive rod.
♦ Remove stud bolt (Part 59); turn out set screws (Parts 31, 32, 33).
♦ Remove radiation shield.
♦ Unscrew nuts on valve cover; remove valve cover, incl. valve stem.
♦ Remove valve cone.

Evaluation :
♦ All dismantled parts, valve block, valve seats.

4.4 Lube Oil System :

Check Lube Oil System


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Procedure :
♦ Drain all operating oil out of the oil tank (4310), suction oil tank (4320), oil cooler (4400) and oil
filter (4510).
♦ Detach and dismantle auxiliary oil pumps (4220, 4230) and emergency oil pumps (4240).

Evaluation :
♦ Impellers, bearing, seal faces, couplings, electric motors.
♦ Reassemble oil pumps and reinstall in oil tank.

Procedure :
♦ Detach and dismantle oil vapor exhauster (4340)

Evaluation :
♦ Impeller, bearing, coupling, electric motor.
♦ Reassemble oil vapor exhauster and reinstall on the oil tank.

Procedure :
♦ Remove inlet strainer from oil tank (4310) and clean.
♦ Clean interior of oil tank.
♦ Reinstall inlet strainer and close drain valve.
♦ Remove, inspect and clean suction-line foot valve.
♦ Clean interior of suction oil tank (4320).
♦ Reinstall valve and close drain valve.
♦ Detach and dismantle lift-oil pumps (4710)

Evaluation :
♦ Gear wheels, bearings, seal faces, couplings, electric motors.
♦ Reassemble and reinstall oil pumps.

Procedure :
♦ Remove, inspect and clean tube bundles in the oil coolers (4400)
♦ Inspect and clean water channels and return boxes.
♦ Reassemble oil cooler.
♦ Dismantle, inspect and reinstall dual three way rotary valve.
♦ Remove and clean filter cartridges in the duplex oil filter (4510), lifting sy stem (4730) and fine-
filtration system (4830).


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♦ Drain rest of oil out of filter shell; clean shell.
♦ Reinstall filter cartridges.
♦ Detach and dismantle oil pumps from the fine-filtration system (4810, 4812).

Evaluation :
♦ Impellers, bearings, seal faces, couplings, electric motors.
♦ Reassemble and reinstall oil pumps.

Procedure :
♦ Fill with clean operating oil.

5.0 NON-DESTRUCTIVE TESTING

5.1 Non-Destructive Inspection :

Test Procedure Test
S# Object Material Remarks
VT MT PT UT Result
1. HP-Rotor 28CrMoNiV49

2. LP-Rotor 26NiCrMoV85

3. LP-Rotor blades X20Cr13
stage 5 +6 left and right

4. Thrust / journal bearing ST52-3N /
Tegostar 738


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5. HP-outer casing-upper part GS-17CrMo55

6. Valve block casing B GS-17CrMoV511

7. HP Joint flange bolts 21CrMoV57 /
24CrMo5

8. HP-inner casing GS-17CrMoV511

9. HP piping GS-17CrMoV511
/14MoV63

10. 4 diffuser studs St52.3 N

11. Main steam inlet GS-17CrMoV511 with
Baroscopic
VT-Visual Testing, MT-Magnetic Testing, PT-Penetrate Testing, UT-Ultrasonic Testing

5.2 Replica Tests :

S# Part Material Position Remarks
1. HP – Piping Main steam inlet / 14MoV63 / Weld seam
elbow GS-17CrMoV511
2. Elbow – outer fiber 14MoV63
3. Elbow – inner fiber 14MoV63
4. HP – Piping, main steam inlet / GS-17CrMoV511
elbow
5. HP – Piping GS-17CrMoV511 /
Elbow / pipe 14MoV63
6. Elbow – outer fiber GS-17CrMoV511
7. Elbow – inner fiber GS-17CrMoV511
8. HP – piping main steam 14MoV63 /
flange / elbow GS-17CrMoV511
9. HP – piping main steam inlet / GS-17CrMoV511 /
pipe 14MoV63


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10. HP – pipe, elbow / pipe GS-17CrMoV511 /
14MoV63
11. Elbow – inner fiber GS-17CrMoV511
12. Elbow – outer fiber GS-17CrMoV511
13. HP Piping 14MoV63 /
Pipe / Elbow GS-17CrMoV511
14. Valve Block B GS-17CrMoV511 /
HP Stop Valve / pipe 14MoV63
15. Valve block B GS-17CrMoV511
HP Stop valve / Control valve
16. Valve Block B GS-17CrMoV511
Control Valve

5.3 Surface Cracks Tests :

S# Method
Part Material Remarks
MPT DPT
1. Journal Bearing / thrust ST52-3N/ White Metal
bearing TEGOSTAR 738
2. LP Rotor 26NiCrMoV85 All transition radius including A-Wheel.
Blades : Stage 5 & 6 left and right
3. H. P. Rotor 28CrMoNiV49 All transition radius including A-Wheel
4. HP Inner Casing GS-17CrMoV511 Complete
Upper and Lower Part
5. HP Piping 14MoV63 / Weld seams & elbows
GS-17CrMo511
6. HP Joint flange bolts 24CrMo5 / All
21CrMoV57
7. HP Outer Casing GS-17CrMo55 Cross section crossings at inner surface.
Upper part
8. Valve Casing Block B GS-17CrMoV511 Cross Section
Crossing Outside
9. Diffuser Studs ST52.3N All


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5.4 Elbows wall thickness measurement :
o
90
STEEL ELBOWS (14MoV63)
Thickness as per drawing – 8.8 mm o
45
Elbow nos. 5, 6, 11 at position 0O, 45 O, 90 O
o
0
INNER FIBER, OUTER FIBER, NEUTRAL FIBER.

CAST STEEL ELBOWS (GS-17CrMoV511)
Thickness as per drawing – 27 mm
Elbow nos. : 1, 2, 3, 4, 7, 8, 9, 10, 12, 13, 14, 15 at positions 0O, 45 O, 90 O
Inner fiber, outer fiber, neutral fiber.

5.5 Boroscopy of Steam Inlet Pipes and emergency stop valves
and control valves internal area.

5.6 Wall Thickness Measurement :

6.0 FACT FINDING :

6.1 Components, Parts and Individual areas to be inspected :

6.1.1 HP Turbine
The following individual parts and areas require inspection :

6.1.1.1 Rotor
♦ A-Wheel blading.


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♦ Moving blades of the first and second expansion lines.
♦ Seal strips : shaft, balancing piston, moving blades.
♦ Bearing journals, front and rear.
♦ Rotor face in the vicinity of bearing oil wiper rings, blading and admission.
♦ Coupling half section, generator end.
♦ Vicinity of mechanical and hydraulic shaft turning gear.
♦ Overspeed trip bolt.

6.1.1.2 Inner Casing :

6.1.1.2.1 Inner Casing, Top Section :

FROM OUTSIDE :
♦ L-Ring grooves, main steam and overload.
♦ Nut support face.
♦ Cast casing.

FROM WITHIN :
♦ Steam admission channels, m ain steam plus overload, upto
stationary blading.
♦ Nozzle blades.
♦ Stationary blades.
♦ Seal strips between stationary blades.
♦ Casing face between stationary blades.
♦ Joint face.
♦ Seal strips of gland bushing (Diaphragm / labyrinth seal).

6.1.1.2.2 Inner Casing, Bottom Section :

FROM OUTSIDE :
♦ L-Ring grooves, main steam plus overload.
♦ Parts comprising lateral palm support and lower axial guide.
♦ Cast casing.


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FROM WITHIN :
♦ Steam admission channels, m ain steam plus overload, upto
stationary blading.
♦ Nozzle blades.
♦ Seal strips between stationary blades.
♦ Joint face.
♦ Seal strips of gland busing (diaphragm, labyrinth seal).

6.1.1.3 Stationary Blade Carrier-I :

6.1.1.3.1 Stationary Blade Carrier-I - Top Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.

FROM WITHIN :
♦ Joint face.
♦ Seal strips.

6.1.1.3.2 Stationary Blade Carrier-I - Bottom Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.

FROM WITHIN :
♦ Joint face.
♦ Seal strips.


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6.1.1.4 Stationary Blade Carrier-II :

6.1.1.4.1 Stationary Blade Carrier-II - Top Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.

FROM WITHIN :
♦ Joint face.
♦ Seal strips.

6.1.1.4.2 Stationary Blade Carrier-II - Bottom Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.
FROM WITHIN :
♦ Joint face.
♦ Seal strips.

6.1.1.5 Stationary Blade Carrier-III :

6.1.1.5.1 Stationary Blade Carrier-III - Top Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.

FROM WITHIN :


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♦ Joint face.
♦ Seal strips.

6.1.1.5.2 Stationary Blade Carrier-III - Bottom Section :

FROM OUTSIDE :
♦ Guide groove.
♦ Cast casing.

FROM WITHIN :
♦ Joint face.
♦ Seal strips.

6.1.1.6 HP Outer Casing :

6.1.1.6.1 HP Outer Casing - Top Section :

FROM OUTSIDE :

FROM WITHIN :
♦ L-ring grooves, main steam plus overload.
♦ Joint face.
♦ Guide faces for stationary blade carriers, I, II and III, plus
balancing piston.
♦ Seal strips; shaft, front; balancing piston; shaft, read.

6.1.1.6.2 HP Outer Casing – Bottom Section :
♦ Joint face.
♦ Seal strips : shaft, front balancing piston, rear.
♦ Eccentric bushings, anti-rotation pin, seal covers for balancing
piston, inner casing, stationary blade carriers I, II, III.

6.1.2 LP Turbine


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The following individual parts and areas require inspection :

6.1.2.1 Rotor
♦ Moving blades.
♦ Seal strips between the blade rows and around the shaft seals.
♦ Balancing weights.
♦ Rotor face (in the steam section and in the area of the bearing oil wiper rings).
♦ Bearing journals.
♦ TE and GE coupling half sections.
♦ Couplings bolts and nuts.

6.1.2.2 LP Inner Casing :

6.1.2.2.1 LP Inner Casing - Top Section :

FROM OUTSIDE :
♦ Casing finish.

FROM WITHIN :
♦ Joint face.
♦ Casing finish.
♦ Seal strips.

6.1.2.2.2 LP Inner Casing - Bottom Section :
♦ Joint face.
♦ Seal strips.
♦ Casing finish.
♦ Lateral and axial guide.

6.1.2.3 LP Stationary Blade Carrier :

6.1.2.3.1 LP Stationary Blade Carrier - Top Section :


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FROM OUTSIDE :
♦ Guide faces, front / rear.
♦ Casing finish.

FROM WITHIN :
♦ Casing finish up to diffuser outlet.

6.1.2.3.2 LP Stationary Blade Carrier - Bottom Section :

FROM OUTSIDE :
♦ Guide faces, front / rear.
♦ Casing finish.

FROM WITHIN :
♦ Casing finish up to diffuser outlet.
♦ Lateral support and axial guide.

6.1.2.4 LP Outer Casing

6.1.2.4.1 LP Outer Casing - Top Section :
♦ Flange connection, admission.
♦ Rupture disk.
♦ Interior finish.
♦ Guide faces for stationary blade carrier.
♦ Seal strips, front and rear shaft seals.
♦ Casing finish between shaft seal strips.

6.1.2.4.2 LP Outer Casing - Bottom Section :
♦ Flange connection, admission.
♦ Rupture disk.
♦ Interior finish.
♦ Guide faces for stationary blade carrier.
♦ Seal strips, front and rear shaft seals.
♦ Casing finish between shaft seal strips.


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♦ Eccentric bushings and anti-rotation pin of the axial guide for
the inner casing and stationary blade carrier.

6.1.3 Journal and Thrust Bearings
The following components, parts and individual areas must be inspected :

6.1.3.1 HP Journal Bearing

6.1.3.1.1 HP Journal Bearing – Top-half Shell ;
♦ Babbitt lining.
♦ Spherical area of bearing shell.
6.1.3.1.2 HP Journal Bearing – Bottom-half Shell ;
♦ Babbitt lining.

6.1.3.2 LP Journal Bearing

6.1.3.2.1 LP Journal Bearing – Top-half Shell ;
♦ Babbitt lining.

6.1.3.2.2 LP Journal Bearing – Bottom-half Shell ;
♦ Babbitt lining.

6.1.3.3 Thrust Bearing

6.1.3.3.1 Thrust Bearing – Top-half Shell ;
♦ Babbitt lining of thrust bearing segments.
♦ Bearing body of top-half shell.

6.1.3.3.2 Thrust Bearing – Bottom-half Shell ;
♦ Babbitt lining of thrust bearing segments.
♦ Bearing body of top-half shell.

6.1.4 Bearing Pedestal

6.1.4.1 Front HP Bearing Pedestal

6.1.4.1.1 Front HP Top-half Bearing Pedestal


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♦ Bearing oil wiper ring seal strips.
♦ Joint plane of top-half bearing pedestal.
♦ Inside surface of top-half bearing pedestal.
6.1.4.1.2 Front HP Bottom-half Bearing Pedestal
♦ Joint plane of bottom-half bearing pedestal.
♦ Inside surface of bottom-half bearing pedestal.

6.1.4.2 Rear HP Bearing Pedestal

6.1.4.2.1 Rear HP Top-half Bearing Pedestal
6.1.4.2.2 Rear HP Bottom-half Bearing Pedestal

6.1.4.3 Rear LP Bearing Pedestal

6.1.4.3.1 Rear LP Top-half Bearing Pedestal

6.1.4.3.2 Rear LP Bottom-half Bearing Pedestal

6.1.5 Valve Blocks

6.1.5.1 Emergency Stop Valve

6.1.5.1.1 Emergency Stop Valves, Steam-side Insert
♦ Valve stem.
♦ Valve cone.


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♦ Valve stem bushing.
♦ Valve cone bushing.
6.1.5.2.1 Emergency Stop Valves, Drive-end
♦ Piston rod.
♦ Piston plate.
♦ Piston.
♦ Spiral springs.
♦ Piston rod guide sleeve.

6.1.5.2.3 Steam Strainers
♦ Steam strainer coiling strip.
♦ Steam strainer basket.
♦ Steam strainer body.

6.1.5.2 Control Valve

6.1.5.2.1 Control Valves, Steam-side Insert
♦ Valve stem.
♦ Valve cone.
♦ Valve stem bushing.
♦ Valve cone bushing.

6.1.5.2.2 Control Valves, Drive end
♦ Bars.
♦ Compression springs.
♦ Leverbar mount.
♦ Parts of control cylinder.

6.1.5.2.3 Valve Block Body
♦ Valve seats “emergency stop and control valve”
♦ Inside face of valve block.
♦ Stud bolts on valve block.

6.2 Component / Part Findings Checklist :

Blading :
♦ A-Wheel / C-Wheel blades.
♦ Stationary / moving blades.


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Blade Tip

Integrated Shrouding :
♦ Radial rubbing ?
♦ Axial rubbing ?
♦ Pitting ?
♦ Gap formation ?
♦ Fused-on foreign particulars ?

Riveted Shrouding :
♦ Axial rubbing ?
♦ Pitting ?
♦ Rivet-tenon damage ?
♦ fused-on foreign particles ?

Milled Edges :
♦ Axial rubbing ?
♦ Foreign-object damage ?

Vane :
♦ Fractures ?
♦ Incipient cracks ?
♦ Axial rubbing ?
♦ Deposits ?
♦ Pitting or crevice corrosion ?
♦ Solid-particle erosion ?
♦ Droplet-impact erosion ?

Blade Root :
♦ Blade fit ?


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• loosening?
• incipient cracks ?
• fracture ?
♦ Finger-pin root connections ?

Measurements :
♦ Static Natural Frequency.
♦ Dimensions.

Tests / Examinations :
♦ Magnetic Particle Test.
♦ Liquid penetrate Test.

Seal Strips :
♦ In shaft seals, In balancing piston, In casing between stationary blades, In rotor between
stationary blades.
• Seal strip fracture ?
• Deformation ?
• Radial rubbing ?
• Axial rubbing ?
• Burring due to rubbing ?
• Unacceptable abrasion ?
• Scale formation ?
• Seal-strip elasticity?

Bearing Journal :
♦ Scoring ?

Thrust-bearing gland housings :
♦ Scoring ?
♦ Parallelism ?

Rotor Faces:


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♦ Incipient cracking ?
♦ Scoring ?
♦ Deposits ?
♦ Corrosion ?

Coupling half section : (Face area – centering – coupling bolt bore)
♦ Frictional oxidation ?
♦ Scoring ?

L-Ring Grooves :
♦ Scoring ?
♦ Scale formation ?
♦ Deformation ?

Nut Support Face :
♦ Scoring ?

Cast Casing :
♦ Deposits ?
♦ Pitting or crevice corrosion ?
♦ Erosion corrosion ?

Nozzle Blades :
♦ Solid-particle erosion ?
♦ Deposits ?
♦ Nozzle-blade fit ?

Joint faces :
♦ Leak-tightness ?
♦ Deformation ?
♦ Damage ?

Design features “Thermo-elastic Casing Guidance”
♦ Functionability impaired ?


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♦ Deposits ?
♦ Scoring ?
♦ Abrasion ?
♦ Seat mobility ?
♦ Deformation ?
♦ Fractures ?

Coupling bolt :
♦ Scoring ?
♦ Frictional oxidation ?

Balancing weights :
♦ Fit in mounting groove ?
♦ Droplet-impact erosion ?

Flanged connections :
♦ Deformation ?
♦ Damage ?

Rupture disk :
♦ Damage ?

Bolts :
♦ Fractures ?
♦ Relaxation ?

Babbitt lining :
♦ Visual damage to surface ?
♦ Damage to babbit lining determ ined via surf ace crack exam ination according to the liquid-
penetrant method ?


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♦ Unacceptable large areas without adequate bond between the lining and the bearing body ,
determined via ultrasonic testing ?
♦ Functionability impaired due to :
• Unacceptable bearing contact angle ?
• Unacceptable lateral or top clearance ?

Bearing shell :
♦ Quality of finish ?

Pedestal faces :
♦ Corrosion ?
♦ Damaged ?

Valve stem :
♦ Damage ?

Guide sleeves / bushings :
♦ Quality of guide bore finish ?
♦ Damage ?

Piston rod :
♦ Damage ?

Piston :
♦ Damage ?

Spiral springs :


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♦ Damage ?

Steam strainer coiling strip :
♦ Damage ?
♦ Foreign objects ?

Steam strainer basket :
♦ Damage ?

Steam strainer body :
♦ Damage ?
♦ Steam strainer support ?

Bars :

Leverbar mount :

Control cylinder assembly :

Valve seat ?
♦ Damage ?

6.3 List of Fact-finding tools, instruments and accessories :
“How-to” Guide for inspection, measuring, testing.

How to inspect ?

Visual Inspection :

Typical accessories :


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♦ Flashlight (halogen lamp).
♦ Photoflood.
♦ Magnifying glass (5 – 10 x)
♦ Mirrors (with and without illumination).
♦ Endoscope (rigid or flexible).

Visual / Manual Inspection :

Typical accessories :
♦ Hand-hammer (200 – 300 gr)
♦ Screwdrivers (approx. 300mm long)

How to Measure ?

Manual measuring :

Typical accessories (measuring tools) :
♦ Tape measure (fabric or metal).
♦ Vernier and / or dial calipers.
♦ Feeler gages.
♦ Micrometers.
♦ Micrometer calipers.
♦ Depth gages.
♦ RC generators.

How to Test ?

Manual testing :
♦ Liquid Penetrant Test.
♦ Magnetic Particle Test.
♦ Ultrasonic Examination.
♦ Electric Crack-Depth Measurements.
♦ X-Ray Examination.

Typical accessories (test instruments / agents) :
♦ Cleaning agents.
♦ Liquid penetrant.


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♦ Developer.
♦ UV lamp.
♦ Yoke Magnet.
♦ Coil Magnet (fluorescent or black magnetic powder carrier fluid).
♦ Pulse-echo test instruments (transducers / sensors of various size).
♦ Potential Probe.

6.4 List of Potential Findings :

Blades

Blades Tips
♦ In order.
♦ Radial rubbing.
♦ Radial rubbing, scoring.
♦ Axial rubbing.
♦ Axial rubbing, scoring.
♦ Radial rubbing, scoring and measurable gap.
♦ Crevice corrosion.
♦ Fused-on foreign particles under shrouding.
♦ Broken rivet head.
♦ Broken rivet shank.
Vane
♦ Broken vane.
♦ Cracked vane.
♦ Axial rubbing on :
• Leading edge.
• Trailing edge
♦ Foreign object damage :
• Roughened - leading edge.
• Dented - trailing edge
• Notched - convex side.
• Torn - concave side
♦ Coatings (scale, deposit) :
• where ? - convex side, concave side.
• extent ? - thin, thick.


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• color ? - rusty brown, grayish white.
• adhesion ? - adherent, easily, removable, water soluble.
• chem.. analysis- completed ? by whom ? corrosive constituents ?

♦ Pitting :
• On the convex side.
• On the concave side.
♦ Solid particle erosion :
• Leading edge, convex side.
• Leading edge, concave side.
• Trailing edge.

Blade Root
♦ Ring test in order (pure, clear sound).
♦ Ring test indicating loose fit (clanking sound).
♦ Measurable gap formation between 2 blades.
♦ Locking / end blade risen more than permissible (0.3 mm).
♦ Broken blade root.
♦ Cracked blade root.

Seal Strips
♦ Broken off around the entire circum ference above caulking groove; broken
out in part (%).
Note : Rectangular fractures indicate stress corrosion.
Curved fractures indicate vibration as the cause of cracking.
♦ Bent due to foreign-object impact.
♦ Wavy deformation (rippling) due to radial rubbing
♦ Bent forward due to axial rubbing.
♦ Bent backward due to axial rubbing.
♦ Unacceptable abrasion due to radial rubbing.
♦ Perceptible burring.
♦ Residual strip height (measured).
♦ Scale formation : in which area….?.
♦ Scaly strips susceptible to brutal fracture.
♦ Elastic seal strips.


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Bearing Journals
♦ In order.
♦ Shallow scoring.
♦ Random scoring along the journal length.
♦ Scoring at the journal ends.
♦ Individual gouges (depth ?).

Thrust Bearing Collar
♦ In order
♦ Shallow scoring, randomly distributed around annulus.
♦ Pronounced scoring on the collar side accom modating residual axial thrust
in positive direction (in negative direction).
♦ Deep individual gouges in the positive collar (in the negative collar).
♦ Thrust bearing collars located in parallel.
♦ Collar faces located in a conical attitude to each other (m echanical repair
work necessary).

Rotor Faces
♦ In order.
♦ Scaled.
♦ Corroded.
♦ Eroded.
♦ Covered with deposits.
♦ Rub marks.
♦ Striated.
♦ Cracked (crack depth ?)

Coupling Half Section
♦ In order
♦ Frictional oxidation.
♦ Fretting corrosion.
♦ Scoring.


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♦ Concave deformation of face area.
♦ Anti-rotation pins sheared off.

L-ring Grooves
♦ In order.
♦ Scaled.
♦ Oval deformation.
♦ Scoring.

Nut Support Faces
♦ In order.
♦ Deep galling.

Cast Casing
♦ In order.
♦ Torn.
♦ Covered with deposits.
♦ Corroded.
♦ Eroded.
♦ Corrosion-erosion attach.
♦ Washed-out casting pores.
♦ Washed-out casting cavities.
♦ Oval deformation.

Nozzle Blades
♦ In order.
♦ Solid particle erosion.
♦ Scaling.
♦ Foreign particle hammering.
♦ Torn seal welds.
♦ Loose nozzle-blade seat.

Joint Faces
♦ In order.
♦ Scaling.
♦ Signs of steam leakage without material erosion.


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♦ Signs of steam leakage with material erosion.
♦ Deformation.

Structural Elements :
“Thermo-elastic Housing Guide”
♦ In order.
♦ Unimpeded movement.
♦ Binding movement.
♦ Seized.
♦ Scaled.
♦ Torn.
♦ Deformed.
♦ Hammered.
♦ Striated.
♦ Abrasion.

Coupling Bolt
♦ In order.
♦ Scored from dismantling.
♦ Unacceptable stretch.

Balancing Weights
♦ In order.
♦ Droplet-impact erosion.
♦ Loose fit in mounting groove.

Flanged Connections
♦ In order.
♦ Concave deformation of face area.
♦ Leaky.
♦ Steam erosion marks without material abrasion.
♦ Steam erosion marks with material abrasion.
♦ Torn.
♦ Contact face for seal grooved indented.


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Rupture
♦ In order.
♦ Damaged

Bolts
♦ In order.
♦ Torn.
♦ Broken off.
♦ Unacceptable stretch.
♦ Scaled thread flanks.
♦ Galled.

Babbitt Lining
♦ In order.
♦ Colored oil deposits.
♦ Full-width scoring.
♦ Scoring at front and rear.
♦ Scoring in the vicinity of lift-oil pressure relief hole.
♦ Round foreign objects stuck in Babbitt metal.
♦ Isolated wide / deep scoring.
♦ Cavitations at front of out-let side oil groove.
♦ Smearing.
♦ Babbitt fretting.
♦ Surface pores.
♦ Crack in Babbitt lining.
♦ Bond in order.
♦ Unacceptably large areas without adequate bond between the Babbitt lining
and the bearing body.
♦ Bearing contact angle in order.
♦ Bearing contact angle too wide.
♦ Clearances in order.
♦ Lateral or top clearance too small or too large.


Page 43 of 75

Bearing Shell
♦ In order.
♦ Spherical area damaged by frictional oxidation.
♦ Spherical area dispels evidence of hammering due to bearing vibration.
♦ Evidence of hammering on the pedestal guide faces.

Pedestal Faces
♦ In order.
♦ Rusty.

Valve Stems
♦ In order.
♦ Scaling.
♦ Axial scoring.
♦ Gland corrosion.
♦ Radial vibration marks.
♦ Torn at cone.
♦ Surface cracks in the hard-facing.
♦ Torn in the spindle.
♦ Torn at the coupling.
♦ Unacceptable bending.

Valve Cones
♦ In order.
♦ Foreign objects pressed into valve seat.
♦ Valve seat torn.
♦ Valve broken.
♦ Valve blow out.
♦ Back seal blown out.
♦ Taper shank scored.
♦ Hard-facing torn at taper shank.
♦ Taper shank scaled.
♦ Pilot cone leaky.
♦ Pilot cone seized.
♦ Signs of hammering on the anti-rotation device.
♦ Anti-rotation device in order.


Page 44 of 75

♦ Anti-rotation device worn.

Guide Sleeves / Bushings
♦ In order.
♦ Scored.
♦ Beaten out on one side.
♦ Back seal indented.
♦ Back seal blown out.
♦ Clearance too large or too small.

Piston Rod
♦ In order.
♦ Scored.
♦ Bent.
♦ Torn.

Piston Plate
♦ In order.
♦ Damaged seal face.
♦ Torn seal face.
♦ Corroded.
Piston
♦ In order.
♦ Damaged seal face.
♦ Corroded.

Spiral Springs
♦ In order
♦ Corroded.
♦ Broken.

Steam Strainer Coiling Strip


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♦ In order.
♦ Torn
♦ Noticed
♦ Round foreign objects stuck in coiling strip.
♦ Signs of hammering.
♦ Broken out.

Steam Strainer Basket
♦ In order.
♦ Torn
♦ Bent guide pins.

Steam Strainer Body
♦ In order.
♦ Damaged.

Bars
♦ In order.
♦ Bent.

Lever mount
♦ In order.
♦ Mount beater out.

Control Cylinder Assembly
♦ In order

Valve seat
♦ In order.
♦ Cracked.
♦ Broken.
♦ Indented by foreign objects.
♦ Blown out.
♦ Torn weld.
7.0 RE-ASSEMBLY :

7.1 L. P. Turbine :


Page 46 of 75

Prepare Bottom-Half Outer Casing for Reassembly
Procedure :
♦ Remove fitted parallel keys from the front and rear axial casing guides (Z58, 59, 60; Detail Z2, Z4)
♦ Inspect fitted parallel keys and contact faces.
♦ Coat fitted parallel keys with lubricant and install.
♦ Check and record clearances (Z 58, 59, 60; Details Z2, Z4, Section G-G)

Prepare Rear Bearing Pedestal for Reassembly
Procedure :
♦ Install bottom-half bearing; protect journal surface areas.

Insert Rotor
Procedure :
♦ Suspend rotor in the vicinity of the coupling flanges (Z 65) and raise slightly.
♦ Clean rotor and protect against corrosion.
♦ Set down rotor in the support bearing at front and bearing pedestal at rear, thereby ensuring that the
journal surface areas of both bearings are coated with viscous oil.
♦ Install top-half journal bearing.

Replace Top-Half Outer Casing
Procedure :
♦ Suspend top-half outer casing in a horizontal position from the intended lifting bosses and raise
slightly.
♦ Clean top-half outer casing and protect against corrosion.
♦ Install guide bolt in the bottom-half outer casing.
♦ Degrease top-half in the bottom-half outer casing.
♦ Apply uniform layer of bluing ink to the joint face of the top-half outer casing.
♦ Install top-half outer casing on bottom-half outer casing and tighten several joint bolts.

Align Bearing Pedestal and Outer Casing
Procedure :


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♦ Unscrew spacer bolts (Z 58, 59, 60; Section F2-F2, F4-F4) on the bottom -half outer
casing.
♦ Check for full contact between the support brackets and the base plates (Z 58, 59, 60;
Section F2-F2, F4-F4).
♦ Check for full contact between the bearing pede stal and the base plate (Z 58, 60; Section
N4-N4).
♦ Check alignm ent dim ensions (Assem bly data sheet EI, EII) or ascertain via rotor
displacement and record values.
♦ Measure and record the exact values at the outer-casing circumferential profile measuring
points.
♦ Measure and record the exact values at the rear bearing pedestal measuring points.
♦ Record measured values and correct as necessary by way of rotor displacement.
♦ Tighten spacer bolts (Z 58, 59, 69, Section F2-F2, F4-F4)

Remove Top-Half Outer Casing
Procedure :
♦ Remove and store top-half outer casing.
♦ Evaluate bluing imprint.

Install Outer Gland Bushing for clearance Check
Procedure :
♦ Measure and evaluate the exact values at the out er-casing circumferential profile measuring points
and correct as necessary via rotor displacement.
♦ Clean front and rear gland bushings and protect against corrosion.
♦ Apply lubricant to guides.
♦ Swing in front and rear bottom-half gland bushings.
♦ Measure, evaluate and record the horizontal a nd vertical radial clearances between the gland
bushings and the rotor.
♦ Measure, evaluate and record axial movement of rotor in the rear gland bushing.
♦ Remove and store front bottom-half gland bushing.
♦ Measure, evaluate and record axial movement of rotor in the rear gland bushing.
♦ Remove and store rear bottom-half gland bushing.


Page 48 of 75

Remove Rotor
Procedure :
♦ Remove and store rotor.
♦ Protect bottom-half journal bearing and support bearing against damage.

Install and Align Stationary Blade Carrier
Procedure :
♦ Sequence : items 500, 525.
♦ Suspend bottom-half stationary blade carrier in a horizontal position and raise slightly.
♦ Clean bottom-half stationary blade carrier and protect against corrosion.
♦ Coat stationary blade carrier guides with lubricant.
♦ Coat the contact faces of the calottes (Z 58, 59, 60; Sections C2-C2, C4-C4); position m arked
spherical washers (Parts 507, 532) in the bottom-half outer casing.
♦ Install bottom-half stationary blade carrier, thereby ensuring that the spherical washers are properly
seated.
♦ Insert rotor.
♦ Check alignment dimension (Assembly data sheet EI, EII) or ascertain via rotor displacement.
♦ Measure and evaluate the exact values of the outer-casing circumferential profile measuring points
♦ Measure and evaluate the lateral (horizontal) radi al clearance between the stationary blade carriers
and the rotor and correct as necessary via the adjusting elements (Z 58, 59, 60; Section C2-C2, C4-
C4).
♦ Suspend top-half stationary blade carrier in a horizontal position and raise slightly.
♦ Clean top-half stationary blade carrier and protect against corrosion.
♦ Screw guide bolts into bottom-half stationary blade carrier.
♦ Degrease the joint faces on the top and bottom halves.
♦ Place top-half stationary blade carrier in position and tighten several joint bolts.
♦ With the aid of the adjusting elem ents (Z 58, 59, 60; Section C2-C2, C4-C4), vertically
raise and lower the stationary blade carrier in position in order to determ ine the overall
radial clearance between the stationary blade carrier and the rotor; evaluate; center the
stationary blade carrier and record the values.
♦ Apply lubricant to the contact faces of the top calottes (Z 58, 59, 60; Section C2-C2, C4-C4) and
apply marked spherical washers.


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♦ Set up proper clearance between the spherical w ashers and the outer casing; secure adjusting
elements as specified in the drawing; check and record all values.
♦ Remove spherical washers and keep ready for further reassembly.
♦ Measure, evaluate and record axial movement of the rotor.
♦ Raise top-half stationary blade carrier, protect against corrosion and store.
♦ Check and record the lateral (horizontal) radial clearance between the stationary blade carriers and
the rotor.
♦ Measure, evaluate and record the axial clearance between the rotating and stationary blades in
positive and negative direction.
♦ Remove and store rotor.
♦ Check bottom-half journal bearing and support bearing for damage.

Install and align Inner Casing
Procedure :
♦ Suspend bottom-half inner casing in horizontal position and raise slightly.
♦ Clean bottom-half inner casing and protect against corrosion.
♦ Apply lubricant to inner casing guides.
♦ Apply lubricant to contact faces of bottom calottes (Z 58, 59, 60; Section A-A); position the
marked spherical washers (Part 325) in the bottom-half outer casing.
♦ Determine the horizontal L-ring movement in the outer casing.
♦ Install bottom-half inner casing, thereby ensuring that the spherical washers are properly seated.
♦ Insert rotor.
♦ Check alignment dimensions (assembly data sheet EI. EII) or ascertain via rotor displacement.
♦ Measure and evaluate the lateral (horizontal) radial clearance between the inner casing
and the rotor and correct as necessary via the adjusting elements (Z 58, Section A-A).
♦ Suspend top-half inner casing in a horizontal position and raise slightly.
♦ Clean top-half inner casing and protect against corrosion.
♦ Screw in guide bolts of the bottom-half inner casing.
♦ Degrease the joint faces of the top and bottom halves.
♦ Mount top-half inner casing and tighten several joint bolts.


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♦ With the aid of the adjusting elem ents (Z 58, 59, 60; Section A-A) vertically raise and lower the
inner casing up to stop in order to determ ine the overall radial clearance between the inner casing
and the rotor; evaluate; center the inter casing and record all values.
♦ Apply lubricant to the contact faces of the top calottes (Z 58, Section A-A) and install m arked
spherical washers.
♦ Set up proper clearance between the spherical w ashers and the outer casing; secure adjusting
elements as specified on drawing; check and record all values.
♦ Remove spherical washers and keep ready for further assembly.
♦ Measure, evaluate and record the axial movement of the rotor.
♦ Lift off top-half inner casing, protect against corrosion and store.
♦ Check and record the lateral (horizontal) radial clearance between the inner casing and the rotor.
♦ Measure, evaluate and record the axial clearance between the rotating and stationary blades in
positive and negative direction.
♦ Remove rotor and store.
♦ Check bottom-half journal bearing and support bearing for damage.

Install Inner Components
Procedure :
♦ Clean interior of bottom -half outer casing and associated inner com ponents and protect against
corrosion.
♦ Insert rotor.
♦ Check alignment dimensions (Assembly data sheet EI, EII) or ascertain via rotor displacement.
♦ Loosely mount rear top-half bearing pedestal.
♦ Suspend top-half inner casing in horizontal position and raise slightly.
♦ Clean top-half inner casing and protect against corrosion.
♦ Degrease joint faces of top and bottom halves; apply uniform coat of sealant to one joint face.
♦ Mount top-half inner casing and tighten joint bolts as specified.
♦ Install pressure-instrument lines (Z 58, Part 391)
♦ Suspend top-half stationary blade carrier in a horizontal position and raise slightly.
♦ Clean top-half stationary blade carrier and protect against corrosion.


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♦ Degrease joint faces of the top and bottom halves; apply uniform coat of sealant to one joint face.
♦ Mount top-half stationary blade carrier and tighten joint bolts.
♦ Clean front and rear gland bushings and protect against corrosion.
♦ Apply lubricant to guides.
♦ Swing in bottom-half gland bushings.
♦ Degrease joint faces; apply uniform coat of sealant to one side of each pair of joint faces.
♦ Mount top-half gland bushings and tighten joint bolts.
♦ Secure all boltings with spot welds.
♦ Remove all taper pins, jack screws and guide bolts; protect against corrosion and store.
♦ Apply lubricant to top-half guides.
♦ Install spherical washers in the stationary blade carrier and inner casing.

Close Outer Casing
Procedure :
♦ Screw in joint bolts on bottom-half outer casing.
♦ Screw in guide bolts on bottom-half outer casing.
♦ Suspend top-half outer casing from the lifting bosses provided and raise slightly.
♦ Clean top-half outer casing; degrease joint faces of top and bottom halves; apply uniform coat of
sealant to one joint face.
♦ Determine horizontal movement of L-rings (Z 58, Detail X-Y) in the top-half outer casing.
♦ Mount top-half outer casing.
♦ Remove guide bolts and jack screws; protect against corrosion and store.
♦ Tighten joint bolts.
♦ Remove taper pins, protect against corrosion and store.
♦ Install rupture disks and shielding pipes.

Check Alignment and Clearances
Procedure :
♦ Unscrew spacer bolts (Z 58, 59, 60; Section F2-F2, F4-F4) on the bottom -half outer casing;
remove extra washers and retighten the spacer bolts.
♦ Check and record the minimum axial movement (Assembly data sheet) of the rotor.
♦ Remove rear top-half bearing pedestal; raise rotor slightly ; rem ove journal bearing; degrease
bearing and journal area; check and record radial clearance of the journal bearing (Z 58, 60;
Section K4-K4).


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