Turbine Over Hauling Procedure Siemens

S.Rameshkumar Mechanical Maintenance

Siemens, Wesel, Germany NG90/81/45-4IZ +WK80/90/0-3RHP Turb+SA21LP Turb

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

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 :

Turbine Overhauling - Scope of Work

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

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 manufacturers 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


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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). Remove seal rings from the top and bottom halves of the bearing pedestal. Dismantle and store piping from the front top-half bearing pedestal. Remove front top-half bearing pedestal (Z 1). Remove seal rings from the top and bottom halves of the bearing pedestal. 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 :

Attach measuring instrument. 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 :

Attach measuring instrument. 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. Ream out (clean) taper-pin bores. 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). Ream out (clean) taper-pin bores. 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 :

Remove spot welds from the joint bolt nuts. Ream out (clean) taper pin bores.


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Unscrew joint bolts. Lift off top-half gland bushing.

Evaluation :

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

Open and remove Outer Gland Bushing : Procedure :

Remove spot welds from the joint bolt nuts. Dismantle gland steam line. Unscrew joint bolts. Lift off top-half gland bushing. 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. Remove top-half journal bearing. 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 :

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

Slide surfaces, spherical washers. Protect hardware against corrosion and store.

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.

Unscrew joint 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. Remove spot welds from the joint bolt nuts. Ream out (clean) taper-pin bores. 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) Remove spot welds from the joint bolt nuts. Ream out (clean) taper-pin bores.


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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 :

Remove spot welds from the joint bolt nuts. Dismantle gland-steam line. Unscrew joint bolts. Lift off top-half gland bushing. 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. Clean all parts and protect against corrosion.

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. Clean all parts and protect against corrosion.

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 S# Object Material

VT MT PT UT

Test

Result Remarks

1. HP-Rotor

28CrMoNiV49 3 3 2. LP-Rotor

26NiCrMoV85 3 3

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

X20Cr13 3 3 4. Thrust / journal bearing ST52-3N /

Tegostar 738 3 3 3


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5. HP-outer casing-upper part

GS-17CrMo55 3 3

6. Valve block casing B

GS-17CrMoV511 3 3 7. HP Joint flange bolts 21CrMoV57 /

24CrMo5

3 3 8. HP-inner casing

GS-17CrMoV511 3 3 3

9. HP piping GS-17CrMoV511 /14MoV63

3 3 10. 4 diffuser studs

St52.3 N 3 3

11. Main steam inlet GS-17CrMoV511 3 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 /

elbow

14MoV63 /

GS-17CrMoV511

Weld seam

2. Elbow outer fiber 14MoV63 3. Elbow inner fiber 14MoV63 4. HP Piping, main steam inlet /

elbow

GS-17CrMoV511

5. HP Piping Elbow / pipe

GS-17CrMoV511 /

14MoV63

6. Elbow outer fiber GS-17CrMoV511 7. Elbow inner fiber GS-17CrMoV511 8. HP piping main steam

flange / elbow

14MoV63 /

GS-17CrMoV511

9. HP piping main steam inlet / pipe

GS-17CrMoV511 /

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

Pipe / Elbow

14MoV63 /

GS-17CrMoV511

14. Valve Block B HP Stop Valve / pipe

GS-17CrMoV511 /

14MoV63

15. Valve block B HP Stop valve / Control valve

GS-17CrMoV511

16. Valve Block B Control Valve

GS-17CrMoV511

5.3 Surface Cracks Tests :

Method S# Part Material

MPT DPT Remarks

1. Journal Bearing / thrust bearing

ST52-3N/ TEGOSTAR 738

3 White Metal 2. LP Rotor 26NiCrMoV85 3 All transition radius including A-Wheel.

Blades : Stage 5 & 6 left and right 3. H. P. Rotor 28CrMoNiV49 3 All transition radius including A-Wheel 4. HP Inner Casing

Upper and Lower Part GS-17CrMoV511 3 3 Complete

5. HP Piping 14MoV63 / GS-17CrMo511

3 Weld seams & elbows 6. HP Joint flange bolts 24CrMo5 /

21CrMoV57 3 All

7. HP Outer Casing Upper part

GS-17CrMo55 3 Cross section crossings at inner surface. 8. Valve Casing Block B GS-17CrMoV511 3 Cross Section

Crossing Outside 9. Diffuser Studs ST52.3N 3 All


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5.4 Elbows wall thickness measurement :

90o

0o

45o

STEEL ELBOWS (14MoV63) Thickness as per drawing 8.8 mm Elbow nos. 5, 6, 11 at position 0O, 45 O, 90 O

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. Nut support face. 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. Casing face 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. Nut support face. FROM WITHIN :

Joint face. Stationary blades. Seal strips. Casing face between stationary blades.

6.1.1.3.2 Stationary Blade Carrier-I - Bottom Section :

FROM OUTSIDE :




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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 :



6.1.1.4.2 Stationary Blade Carrier-II - Bottom Section :

FROM OUTSIDE :



6.1.1.5 Stationary Blade Carrier-III :

6.1.1.5.1 Stationary Blade Carrier-III - Top Section :

FROM OUTSIDE :



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6.1.1.5.2 Stationary Blade Carrier-III - Bottom Section :

FROM OUTSIDE :



6.1.1.6 HP Outer Casing :

6.1.1.6.1 HP Outer Casing - Top Section :

FROM OUTSIDE :

Nut support face. 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 :

Nut support face. Casing finish. FROM WITHIN :

Joint face. Casing finish. Stationary blades. Seal strips.

6.1.2.2.2 LP Inner Casing - Bottom Section :

Joint face. Stationary blades. 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 :

Stationary blades. 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 :

Stationary blades. 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 ;


6.1.3.2 LP Journal Bearing

6.1.3.2.1 LP Journal Bearing Top-half Shell ;


6.1.3.2.2 LP Journal Bearing Bottom-half Shell ;


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

The following components, parts and individual areas must be inspected : 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

Bearing oil wiper ring seal strips. 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

The following components, parts and individual areas must be inspected : 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 :

Radial rubbing ? Axial rubbing ? Pitting ? Rivet-tenon damage ? fused-on foreign particles ?

Milled Edges :

Radial rubbing ? Axial rubbing ? Foreign-object damage ?

Vane :

Fractures ? Incipient cracks ? Axial rubbing ? Foreign-object damage ? 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 :

Incipient cracking ? Deposits ? Pitting or crevice corrosion ? Erosion corrosion ?

Nozzle Blades :

Solid-particle erosion ? Foreign-object damage ? 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 ? Incipient cracking ? Fractures ? Leak-tightness ?

Coupling bolt :

Scoring ? Frictional oxidation ?

Balancing weights :

Fit in mounting groove ? Droplet-impact erosion ?

Flanged connections :

Functionability impaired ? Deformation ? Leak-tightness ? Damage ?

Rupture disk :

Damage ? Bolts :

Fractures ? Incipient cracking ? 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 :

Quality of finish ? Damage ? Functionability impaired ?

Guide sleeves / bushings :

Quality of guide bore finish ? Damage ? Functionability impaired ?

Piston rod :


Piston :


Spiral springs :


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Steam strainer coiling strip :

Damage ? Foreign objects ?

Steam strainer basket :

Damage ? Steam strainer body :

Damage ? Steam strainer support ?

Bars : Functionability impaired ?

Leverbar mount :

Functionability impaired ? Control cylinder assembly :

Functionability impaired ? Valve seat ?


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. Fretting corrosion. Striated. Abrasion.

Coupling Bolt

In order. Fretting corrosion. 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.


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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.


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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 :


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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 :

Unscrew joint bolts. 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.


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Remove Rotor

Procedure :

Remove top-half journal bearing. 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

and correct as necessary via rotor displacement.

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. Unscrew joint bolts. 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 top-half journal bearing. 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 exact values at the out er-casing circumferential profile measuring points


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. Unscrew joint bolts. 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 top-half journal bearing. 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. Measure and evaluate the exact values at the out er-casing circumferential profile measuring points


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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Install journal bearing for bluing im print; lowe r rotor; bolt down bearing bracket; m ake bluing imprint.

Remove bearing bracket; raise rotor slightly ; remove journal bearing; evaluate bluing im print; clean bluing ink off of bearing and shaft journal.

Install journal bearing; lower rotor; thereby ensuring that the journal surface areas are coated with viscous oil; bolt bearing bracket and install thermocouples (Z 7).

Check for full contact between the support brackets and the base plates (Z 58, 69, 60; Section F2-F2, F4-F4).

Check measuring points on the rear bearing pedestal. Check outer-casing circumferential profile measuring points. Check and record clearances in the front and rear support bracket bolts (Z 58, 59, 60; Section F2-

F2, F4-F4).

Check zeroing of casing axial-position indicator (Z 58, 59, 60; Detail V4). 7.2 H. P. Turbine

Prepare Bottom-half Outer Casing for Reassembly

Procedure :

Apply lubricant to threads and contact faces of axial casing guide calottes (Z 37, 38, 39; Section W1-W1 and W3-W3); turn in calottes such that they no longer protrude out of the bore.

Insert spherical washers into the axial guides and bring into contact with the guide face via the calottes.

Install Center Bearing Pedestal

Procedure :

Suspend center bearing pedestal in horizontal position and raise slightly. Clean bearing pedestal and protect against corrosion. Apply lubricant to contact faces of the calottes in the shoulder (Z 37, 39; Section 03-03, Part 111);

install marked spherical washers.

Apply lubricant to the threads and contact faces of the axial casing guide calottes (Z 37, 39; Section M3-M3, Part 122); turn in calottes such that they no longer protrude from the bore.

Apply lubricant to the eccentric bolt guides (Z 37, 39; Section 03-03, Part 110). Set bearing pedestal down on the spherical washers of the shoulder.


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Insert spherical washers of the axial casing guide and bring into contact with the guide face via the calottes.

Apply lubricant to the threads of the hexagon head bolts; screw in and tighten hexagon head bolts carrying tab washers (Z 37, 39; Section 03-03, Parts 115, 116).

Install bottom-half journal bearing (Z 16) and protect journal surface area against corrosion.

Install Front Bearing Pedestal

Procedure :

Suspend front bearing pedestal in a horizontal position and raise slightly. Clean bearing pedestal and protect against corrosion. Apply lubricant to contact faces of calottes in the shoulder (Z 37, 39; Section 01-01, Part 11) and

install marked spherical washers.

Apply lubricant to the threads and contact faces of the axial casing guide calottes (Z 37, 39; Section M1-M1, Part 22) and turn in calottes such that they no longer protrude from the bore.

Mount bearing pedestal on the spherical washers of the shoulder and center the bearing pedestal axially (Z 37, 38; View V2).

Insert spherical washers of the axial casing guide and bring into contact with the guide face via the calottes.

Apply lubricant to the threads of the stud bolts (Z 37, 38; Detail T1, Parts 60-63); screw stud bolts into the outer casing and secure with lock nuts; screw on but do not tighten the adjusting nuts.

Mount brackets (Z 37, 38; Section 01-01, Part 15); apply lubricant to threads of spacer bolts (Section 01-01, Part 16).

Apply additional washer to spacer bolts (Z 71, Detail E); screw in spacer bolts hand-tight. Install bottom-half journal bearing (Z 2); protect journal surface area from corrosion.

Insert Rotor

Procedure :

Suspend rotor in horizontal position and raise slightly. Clean complete rotor and protect against corrosion. Set down rotor in the bearing pedestal, thereby ensuring that both journal surface areas are coated

with viscous oil.

Mount top-half journal bearing.

Replace Top-Half Outer Casing

Procedure :


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Apply lubricant to the contact faces of the calottes of the front support bracket seat (Z 37, 38; Section P1-P1); install marked spherical washers.

Suspend top-half outer casing from the lifting bosses provided and raise slightly. Screw guide bolts into the bottom-half outer casing. Degrease joint faces of top-half and bottom-half outer casing. Apply uniform layer of bluing ink to the joint face of the top-half outer casing. Mount the top-half outer casing on the bottom-half outer casing and tighten several joint bolts. Unscrew bolts of auxiliary support brackets (Z 37, 38; Section P1-P1, Part 30).

Align Bearing Pedestal and Outer Casing

Procedure :

Position and apply load to lifting fixture (Z 21). Remove support bearing. Connect LP rotor to HP rotor with at least 4 coupling bolts (Z 72) Pull coupling flange halves to within 3 mm and hand-tighten the coupling nuts. Take load off of lifting fixture (Z 21). Unscrew spacer bolts (Z 37, 38, 39; Section 01-01, P3-P3) on the front bearing pedestal and outer

casing.

Measure and evaluate the shaft alignment between the HP and LP turbines and correct as necessary via HP turbine displacement.

Check the dimension L (Assembly data sheet) on the front support bracket seats. Measure the exact value at the front and rear bearing pedestals. If the values deviate by

more than 0.1mm from the values listed in the assembly data sheet, the bearing pedestal

must be re-aligned. The prelim inary alignment status, including any corrections, must

be noted. Then, the rotor can be turned.

Check Alignment dimensions (Assem bly data sheet, E1, EII, EIV) and correct as necessary via displacement of the front bearing pedestal; record all values.

Apply and tighten nuts on the longitudinal guide (Z 37, 38; Detail T1) as specified on the drawing. Install bottom-half thrust bearing, thereby ensuring that the journal surface areas are coated with

viscous oil.

Mount and bolt down the front and center top-half bearing pedestal. Check and record the HP/LP turbine alignment (coupling check). Measure and record the exact values at the LP outer casing circumferential profile measuring point. Measure and record the exact values at the front and center bearing pedestal measuring points. Measure and record the exact values at the outer casing circumferential profiles measuring points.


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Check for full contact of the front support brackets (Z 37, 38; Section P1-P1) and record values. Check for full contact of the rear support brackets (Z 37, 39, Section P3-P3) on the base plates. Evaluate recorded values and correct as necessary , either via shim s between the support brackets

and base plates (Z 37, 39; Section P3-P3) or on the adjusting elements (Z 37, 38, 39).

Secure adjusting elements as per drawing (Z 37, 38, 39). Tighten spacer bolts (Z37, 38, 39; Section 01-01, P3-P3). Unscrew coupling nuts (Z 72). Remove coupling bolts. Accommodate weight of the LP rotor with the aid of the lifting fixture (Z 71). Push coupling flange apart by turning in the jack screws. Push rotor in the positive direction by about 1.0mm ahead of the stop. Install support bearing; take load off of lifting fixture.

Remove Top-Half Outer Casing

Procedure :

Screw in bolts against the auxiliary support brackets of the bottom -half outer casing (Z 37, 38; Section P1-P1, Part 30).

Unscrew joint bolts. Remove and store top-half outer casing. Evaluate bluing imprint.

Install Outer Gland Bushing for Checking Clearances

Procedure :

Measure and evaluate the exact values at the out er-casing circumferential profile measuring points and correct as necessary by adjusting the screws on the auxiliary support bracket.

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 clearance between the gland

bushings and the rotor.

Remove front top-half bearing pedestal. Remove bottom-half thrust bearing. Measure, evaluate and record the axial movement of the rotor in the front gland bushing. Remove and store front bottom-half gland bushing. Measure, evaluate and record the axial movement of the rotor in the rear gland bushing.


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Remove and store rear bottom-half gland bushing.

Remove Rotor

Procedure :

Remove front top-half bearing pedestal; rem ove bottom-half thrust bearing; rem ove top-half journal bearing.

Remove rear top-half bearing pedestal; remove top-half journal bearing. Remove and store rotor. Protect bottom-half journal bearing against damage.

Install and Align Stationary Blade Carrier

Procedure :

Installation sequence : Items 500, 525, 550 (Z43). Suspend bottom-half stationary blade carrier in horizontal position and raise slightly. Clean bottom-half stationary blade carrier and protect against corrosion. Apply lubricant to stationary blade carrier guides. Apply lubricant to contact faces of the calottes (Z 45, Section K1-K3). Position marked spherical washers (Z 45, Section K1-K3, Part 7) in the bottom-half outer casing. Install bottom-half stationary blade carrier thereby ensuring that the spherical washers

are properly seated.

Insert the rotor. Install bottom-half thrust bearing. Measure and evaluate the exact values at the out er-casing circumferential profile measuring points

and correct as necessary by adjusting the screws on the auxiliary support brackets.

Measure and evaluate the lateral (horizontal) radi al clearance between the stationary blade carriers and the rotor and correct as necessary by way of the adjusting elements (Z 45, Section K1-K3)

Suspend top-half stationary blade carrier in a horizontal position and raise slightly. Clean top-half stationary blade carrier and protect against corrosion. Degrease joint faces of top-half and bottom-half stationary blade carrier. Mount top-half stationary blade carrier; tighten several joints bolts. With the aid of the adjusting elem ents (Z 45, Section K1-K3), vertically raise and lower the

stationary blade carrier in order to determ ine and evaluate the overall radial clearance between the

stationary blade and the rotor; center the stationary blade carrier and record the values.


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Apply lubricant to the contact faces of the upper calottes (Z 45, Section K1-K3, Part 9); install marked spherical washers.

Adjust clearance between spherical washers and outer casing; secure adjusting elements; check and record all values.

Remove spherical washers and keep ready for further assembly. Remove bottom-half thrust bearing. Measure, evaluate and record the axial movement of the rotor. Reinstall bottom-half thrust bearing. Unscrew joint bolts. Lift off top-half stationary blade carrier, protect against corrosion and store. Check and record the lateral (horizontal) radial clearance between the stationary blade carrier and

the rotor.

Measure, evaluate and record the axial clearance between the rotating and stationary blades in positive and negative direction.

Remove bottom-half thrust bearing. Remove top-half journal bearing. Remove and store rotor. Protect bottom-half journal bearing against damage.

Install and Align Inner Casing

Procedure :

Suspend bottom-half inner casing in a horizontal position and raise slightly. Clean bottom-half inner casing and protect against corrosion. Apply lubricant to guides and contact faces of the inner casing. Determine the horizontal movement of L-rings in the bottom-half outer casing (Z 37, Section Y-Y) Install bottom-half inner casing, including thermocouples (Z 41). Insert rotor (cf. 2.8.2.4). Install bottom-half thrust bearing. Measure and evaluate the exact values at the out er-casing circumferential profile measuring points


Mount measuring instrument on the rotor. Suspend top-half inner casing in a horizontal position and raise slightly. Clean top-half inner casing and protect against corrosion. Degrease the joint faces of the top-half and bottom-half inner casing.


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Install top-half inner casing and tighten several joint bolts. Measure and evaluate the inner-casing measuring points; correct as necessary via shim s or

eccentric guide (Z 37, Section L-L and Part 335) ; record m easuring values subsequent to any

corrections.

Measure and evaluate the clearance between the upper shim (Z 37, Section L-L) and the outer casing and correct as necessary via shims; record measured values following any corrections.

Remove bottom-half thrust bearing. Measure, evaluate and record the axial movement of the rotor. Reinstall bottom-half thrust bearing. Unscrew joint bolts. Lift off top-half inner casing; protect against corrosion and store. Clean bottom-half gland busing (Z 30) and protect against corrosion. Coat guides with lubricant. Swing bottom-half gland busing into the inner casing. Measure, evaluate and record the horizontal and vertical radial clearance between the inner casing

and the rotor.

Measure, evaluate and record the horizontal and vertical radial clearance between the bottom-half gland bushing and the rotor.

Measure, evaluate and record the axial clearance be tween the rotating and stationary blades in the positive and negative direction.

Remove bottom-half thrust bearing. Measure, evaluate and record the axial movement of the rotor in the gland busing. Remove top-half journal bearing. Removed and store rotor. Protect bottom-half journal bearing against damage.

Install and align the Inner Gland Bushing

Procedure :

Suspend bottom-half gland bushing in a horizontal position and raise slightly. Clean bottom-half gland bushing and protect against corrosion. Apply lubricant to the guides on the gland bushing. Apply lubricant to the contact faces of the calottes (Z 37, Section K-K, Part 288). Install marked spherical washers in the bottom-half outer casing. Install bottom-half gland bushings, thereby ensuring that the spherical washers are properly seated.


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Insert rotor. Install bottom-half thrust bearing. Measure and evaluate the exact values at the out er-casing circumferential profile measuring points


Measure and evaluate the lateral (horizontal) ra dial clearance between the gland bushing and the rotor and correct as necessary via the adjusting elements (Z 37, Section K-K).

Suspend top-half gland bushing in a horizontal position and raise slightly. Clean top-half gland busing and protect against corrosion. Degrease joint faces of top-half and bottom-half gland bushing. Install top-half gland bushing and tighten joint bolts. With the aid of the adjusting elem ents (Z 37, Section K-K), vertically raise and lower the gland

bushing up to stop in order to determ ine and evaluate the overall radial clearance between the

gland bushing and the rotors; center the gland bushing and record all values.

Apply lubricant to the contact faces of the upper calottes (Z 37, Section K-K, Part 289) and install marked spherical washers.

Adjust the clearance between the spheri cal washers and the outer casing; secure adjusting elements; check and record all values.

Remove the spherical washers and keep ready for further assembly. Remove bottom-half thrust bearing. Measure, evaluate, record the axial movement of the rotor. Reinstall bottom-half thrust bearing. Unscrew joint bolts. Lift off top-half gland bushing, protect against corrosion and store. Check and record the lateral (horizontal) radial clearance between the gland bushing and the rotor. Remove bottom-half thrust bearing. Remove top-half journal bearing. Remove and store rotor. Protect bottom-half journal bearing against damage.

Install Inner Components

Procedure :

Clean interior of the bottom -half outer casing and all inner components and protect against corrosion.

Insert rotor (cf. 2.8.2.4).


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Install bottom-half thrust bearing. Check and record alignment dimension (Assembly data sheet EII). Loosely mount front and center top-half bearing pedestals. Suspend top-half stationary blade carrier in a horizontal position and raise slightly. Clean top-half stationary blade carrier and protect against corrosion. Degrease the joint faces of the top-half and bottom-half stationary blade carrier and apply uniform

layer of sealant to one of the faces.

Install top-half stationary blade carrier and tighten joint bolts as specified. Clean top-half gland bushing (Z 30) and protect against corrosion. Degrease joint faces of the top-half and bottom -half inner casing and apply uniform lay er of

lubricant to one face.

Install top-half gland busing and tighten joint bolts as specified. Remove taper pins and secure joints bolts with spot welds. Suspend top-half inner casing in a horizontal position and raise slightly. Clean top-half inner casing and protect against corrosion. Degrease joint faces of top-half and bottom-half inner casing and apply uniform layer of

sealant to one face.

Install top-half inner casing and tighten joint bolts as specified. Install pressure-instrument lines (Z 40, Part 391). Suspend inner top-half gland bushing in a horizontal position and raise slightly. Clean inner top-half gland bushing and protect against corrosion. Degrease joint faces of the top-half and bottom ha lf gland bushing and apply uniform coat of

sealant to one face.

Install inner top-half gland bushing and tighten joint bolts as specified. Clean front and rear gland bushing and protect against corrosion. Apply lubricant to guides. Swing in bottom-half gland bushing. Degrease joint faces of top-half and bottom -half gland bushing and apply uniform coat of sealant

to one face of each gland bushing.

Install top-half gland bushing and tighten joint bolts as specified. Secure all boltings with spot welds. Remove 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 carriers and inner gland bushing.


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Close Outer Casing

Procedure :

Screw in joint bolts of bottom-half outer casing. Screw in guide bolts. Suspend top-half outer casing in a horizontal position from the lifting bosses provided and raise

slightly.

Clean top-half outer casing; degrease joint faces of top-half and bottom -half outer casing; apply a uniform layer of sealant to one of the faces.

Determine the horizontal movement of L-rings (Z 37, Section Y-Y) in the top-half outer casing. Install top-half outer casing. Remove guide bolts and jack screws, protect against corrosion and store. Tighten joint bolts as specified. Remove taper pins, protect against corrosion and store. Loosen auxiliary support bracket bolts (Z 37, 38; Section P1-P1, Part 30), turn back

at least 3mm and secure with counternuts.

Bolt down upper steam inlet lines. Install upper cross-around lines incl. swing disk valves. Install wall temperature sensor (Z 36).

Check Alignment and Clearances

Procedure :

Unscrew spacer bolts (Z 37, 38, 39; Section 01-01, Section P3-P3) on the front bearing pedestal and outer casing, remove extra washers and retighten spacer bolts.

Dismantle front top-half bearing pedestal; remove bottom-half thrust bearing. Raise rotor slightly ; rem ove journal bearing; degrease bolt bearing and shaft journals; check and

record clearance in the journal bearing (Z 37, 39; Section K1-K1).

Install journal bearing and thrust bearing for getti ng bluing imprints; lower rotor; bolt on top-half bearing pedestal and make bluing imprint.

Check and record axial clearance of the thrust bearing (Z 37, 38, Detail X1). Remove front top-half bearing pedestal and check alignment dimensions (Assembly data sheet, EI,

EIII and EIV).

Remove thrust bearing; raise rotor slightly ; remove journal bearing; evaluate bluing imprints and clean bluing ink from bearing and journals.


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Install journal bearing; lower rotor; install thru st bearing, thereby ensuring that the journals of both bearings are coated with viscous oil.

Install thermocouples (Z 7). Install and bolt down front top-half bearing pedestal. Dismantle center top-half bearing pedestal; raise rotor slightly; remove journal bearing degrease

bearing and journal; check and record radial clearance of the journal bearing (Z 37, 39; Section

K3-K3).

Install journal bearing for getting a bluing im print; lower rotor; bolt down top-half bearing pedestal and make bluing imprint.

Dismantle center top-half bearing pedestal; raise roto r slightly; rem ove thrust bearing; evaluate bluing imprint and clean bluing ink from bearing and journal.

Install journal bearings; lower rotor; thereby ensuring that the journal is coated with viscous oil. Install thermocouples (Z 7). Install and bolt down center top-half bearing pedestal. Check front support bracket seat (Z 37, 38; Section P1-P1). Check for full contact between the rear support brackets and the base plates (Z 37, 38; Section P3-

P3).

Check the front and rear bearing pedestal measuring points. Check the outer-casing circumferential profile measuring points. Install manual turning gear; check and record th e clearance between the fram e and the gear wheel

(Z 37, 39; Section U3-U3).

Unscrew cover of front top-half bearing pedestal Z1, Item 169/165); turn turbine rotor to the proper measuring position; pull level of em ergency trip gear (into operating position; Z88) and

lock in place.

Check and record the radial clear ance between the ratchet lever and the overspeed trip bolt (Z 37, 38; Section S1-S1).

Check and record the axial clear ance between the ratchet lever and the stopping cam (Z 37, 38; View R1).

Return lever to its original position; reinstall cover on the front top-half bearing pedestal. Check the maximum and minimum clearances at the front and rear support bracket bolts (Z 37, 38,

39; Section P1-P1, P3-P3).

Check and record the clearances at the casing guides (Z 37, 38, 39; Section W1-W1, W3-W3). Check and record the clearances at the lower bearing pedestal guides (Z 37, 38, 39; Section M1-

M1, M3-M3).


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