ALIGNMENT OF TURBINE GENERATOR

ALIGNMENT OF TURBINE GENERATORPRESENTATION BYANANDAGOWROW SHETTY1CONTENTSALIGNMENT.

OBJECTIVE OF TURBINE, GEARBOX AND ALTERNATOR ALIGNMENT.

HUB SHRINK FIT

INSTRUMENTS IN ALIGNMENT OF TG SET.

PARTS INVOLVED IN ALIGNMENT OF TG SET.

STEPS INVOLVED IN ALIGNMENT

GROUTING OF TURBINE AND ALTERNATOR

PLACING OF CONDENSER

QUALITY CHECKS.

OBSERVATION MADE AT SITE

SUGGESTIONS.

CONCLUSION.

2ALIGNMENT:

It is the adjustment of an object in relation with other object (or) A static orientation of some object or set of objects in relation to other.

ALIGNMENT OBJECTIVE OF TURBINE, GEARBOX AND ALTERNATOR ALIGNMENT

To ensure axis of turbine rotor and pinion and also axis of gear and alternator shaft are co-axial at hot running condition and it is parallel to the ground.

To avoid incorrect meshing of gears, over heating of bearings and to reduce vibrations.

To increase the life of couplings.4HUB SHRINK FITTING METHODVesselTransformer oil (~200c for 3 hrs)Coupling hubHeating source support1. Heat the hub with the help of a heating source using transformer oil up to 200c .2. Slow heating should be done for uniform heating.3. Once the required temperature is attained measure the dimension of inner diameter of the hub.

+0.042 +0.0172506252504. If required expansion is achieved takeout the hub and fix it to the alternator shaft and place the key b/w the hub and shaft-0.03-0.05Alternator shaftkeyCoupling hub5620120.150.20-0.07432-0.1656-0.03-0.2156Max interference= 0.092mmMin interference=0.047mm

INSTRUMENTS AND EQUIPMENTS USED IN ALIGNMENT Master level Dial indicators Dial indicator holder Feeler gauges Vernier caliper Inside and outside micrometer Plumb Hammer Spanner Hydraulic jack F-rodPARTS INVOLVED IN ALIGNMENT OF TG SET

Turbine rotor Pinion shaft Gear shaft Alternator rotor Leveling pads Taper wedges Shim plates Jacking screws Foundation bolts and nuts Barring gearSYSTEM SPECIFICATIONDBSE of SCG-3 - HSC - 550mm LSC 500mm

Master level reading on levelling pads - 0.02 mm/m

Dimension of shim plate - 75mm*150mm*X (0.05 to 1mm)

Dimension of packing plate - 75mm*150mm*X (1 to 25mm)

Dump and float of rotor - 0.8 to 0.9 & 0.25 to 0.3mm

Dimension of taper wedge - 75mm*150mm*(14 to 20 mm)=2.29

ALIGNMENT PROCEDURE FOR HSC Turbine and gear box unit is placed on the foundation block. Using jacking screw lift the turbine approximately to a height of grouting thickness of 50mm and Place shim plates or taper wedges with additional steel plates if required in between sole plate and packer plate to support. Check level of turbine at each leveling pad and compare it with the values of QA report received from shop floor.Insert the foundation bolts from bottom and hand tighten the foundation bolt, ensure that anchor plate is having maximum contact with the concrete surface .

Foundation boltJacking screwTaper wedgesMaster levelsole plate5.A dial indicator holder is made to fix two dial indicators ,which is held by one base and which will be connected to the turbine rotor flange using nut and bolt.6.One of the dial indicator will be placed on the pinion flange face to check parallelism.7The second dial indicator will be placed on the radial surface of the pinion flange to check the radial out .8Rough reading of radial run out and parallelism between the flanges has to be recorded after leveling the base plate using master level.Tighten the foundation bolts and check the level and alignment reading.Repeat the procedure of tightening and loosening of foundation bolt to get alignment reading and level reading with in the tolerance .ALIGNMENT PROCEDURE FOR HSC

PROCEDURE FOLLOWED DURING FINAL ALIGNMENT OF HSC 0.000.400.800.40RADIAL(DESIGN)RADIAL (AT SITE)0.000.600.900.300.00+0.010.00-0.01INFERENCE: According to the requirement the side out is zero but from the reading pinion axis is (0.60-0.30=0.30) 0.15 mm to the right of rotor axis and the pinion axis which has to be 0.40mm down from rotor axis is down by 0.45mm.

FACIAL(AT SITE)FACIAL(DESIGN)0.00

0.000.000.00(TOLERANCE= 0.05mm)(TOLERANCE= 0.05mm)PROCEDURE FOLLLOWED DURING FINAL ALIGNMENT OF HSC ACTION: Foundation bolts under rotor casing on the right side seeing from steam end are tighten so that rotor shifts to right so that side out reduces.Gear box is slightly lifted by hammering taper wedges between sole plate and packer plate under gear box so that 0.90mm reduces to 0.8mm. 0.000.400.800.40RADIAL(DESIGN)RADIAL (AT SITE)0.000.600.900.300.00+0.010.00-0.01FACIAL(AT SITE)FACIAL(DESIGN)0.00

0.000.000.00(TOLERANCE= 0.05mm)(TOLERANCE= 0.05mm)

ALIGNMENT PROCEDURE FOR LSC WITH TDPS ALTERNATORSole plateFoundation boltALIGNMENT PROCEDURE FOR LSC WITH TDPS ALTERNATORAlternator should be placed to match centerline line of alternator with that of gear shaft.Level the alternator by placing master level on the sole plate of alternatorHigh speed coupling must be removed during low speed alignment.The gear wheel must be positioned in its mid position and alternator in its magnetic center position and get the required DBSE.

Match this marked line with the step as shown5. Using the jacking screw set the height of alternator to a height of gear wheel axis and pack the gap between sole plate and packer plate with taper wedge and shim plate simultaneously.6. Align the alternator to get parallelism with in 0.02 mm and radial runout as per design with a tolerance of 0.05 mm.

ALIGNMENT PROCEDURE FOR LSC WITH TDPS ALTERNATOR0.00-0.27-0.080.19 -0.030.120.150.00+0.000.02-0.01INFERENCE: According to the requirement the alternator axis should have been to the left of gear wheel axis by 0.23mm seeing from steam end but it is (0.15+0.03=0.18) 0.09mm and alternator axis should have been 0.04mm above gear wheel axis but it is down by 0.06 mm. RADIAL(DESIGN)RADIAL (AT SITE)FACIAL(AT SITE)FACIAL(DESIGN)(TOLERANCE= 0.05mm)(TOLERANCE= 0.05mm)0.000.000.000.000.00ALIGNMENT PROCEDURE FOR LSC WITH TDPS ALTERNATORAction: To make the alternator axis to be above gear wheel axis lift the alternator by hammering the taper wedge between alternator sole plate and alternators packer plate to a height of 0.1mm. Shift alternator towards left by 0.14 mm by jacking on right side of the alternator. To correct facial we need to lift exciter side of the alternator or take it down at the front. 0.00-0.27-0.080.19 -0.030.120.150.00+0.000.02-0.01RADIAL(DESIGN)RADIAL (AT SITE)FACIAL(AT SITE)FACIAL(DESIGN)(TOLERANCE=0.05mm)(TOLERANCE= 0.05mm)0.000.000.000.000.00ALIGNMENT PROCEDURE FOR LSC WITH TDPS ALTERNATORGROUTING OF TURBINE AND ALTERNATOR Once the alignment is over TG set is ready for groutingCalculate the volume of grouting cement mixture required to cover the grouting area.Build restraint around the turbine, generator and exhaust cutout. Prepare the grouting mixture using a grouting mixer in the ratio of 8 liters of water for every 50 kg of grouting cementPour this mixture continuously without giving time for grouting cement get dry in b/w till the whole grouting area is covered with grouting mixture.To get uniform distribution of grouting cement all over the area we should use vibrator and ensure grouting cement flows out at the exhaust cut out.Then the system is left for seven days for complete curing.

1. Condenser has two stools for support. 2. The condenser unit should be placed on one concrete support stool,cast as per drawing. 3. Position condenser to match with center line of turbine exhaust flange in both the axis.4. Support the other end of condenser on temporary support.ERECTION OF CONDENSER SYSTEMCONDENSER ALIGNMENTAlignment of condenser starts with fixing of spool piece with turbine exhaust flange.80% blue matching of spool piece flange is achieved by using a glass slab of 10 to 15mm thick and then it is bolted to the turbine exhaust flange.

Exhaust flangespoolBellow Condenser inlet flangeALIGNMENT OF CONDENSER SYSTEM

Insert the coupler over the spool piece and tack weld.Now lift the bellow piece and place it in b/w spool and condenser inlet flange. Maintain a gap of 15 to 25 mm b/w spool piece to bellow. Remove the tack weld, place the coupler in position so that the coupler covers both spool piece and bellow. Weld coupler to both spool piece and bellow.

Bellow CondenserCooling water outletCooling water inletConnecting flangeALIGNMENT OF CONDENSER SYSTEM By adjusting the condenser ,align the center line of the condenser with that of turbine exhaust.Grout the fixed support.

Condenser legTeflon Ms plateConcrete stoolMS plate and TEFLON sheet for sliding support.QUALITY CHECKSInterference of coupling hub and alternator shaft (0.05 to 0.1mm ).Level on each leveling pad with 0.02 mm/m allowance on values given from QA report of shop floorTurbine level on bearing journal (0.02 mm/m.).DBSE (0.3 to 0.5mm).Final alignment readings Radial (0.05mm) Facial (0.02mm)

COMMON CHECKSElevation of each packer plate.Whether load is acting on all shim plates .Tightening of all foundation bolts.Whether foundation bolt anchor plate is having sufficient contact .There is clearance all around the foundation bolt.Parallelism of all steam pipes connected to turbine is within (+/- 0.15 to 0.2mm) and all bolts are freely moving in the bolt holes.Using glass slab of 10 to 12 mm thick , spool piece is blue matched for 80% before it is connected to exhaust flangeCare should be taken that alignment is not disturbed during welding of bellow and spool using coupler.Proper earthing should be provided while welding

OBSERVATION MADE AT SITE KIRI DYES: Foundation bolt broken.

SUTLEJ TEXTILES: Foundation bolt deformed.

3. KIRI DYES: Contractor had filed the leveling pads.

4. KIRI DYES: Hand grinded packer plate were used.

KIRI DYES: Turbine sole plate was deformed.

6. KIRI DYES: Seating area of taper wedge and sole plate is less.

OBSERVATION MADE AT SITEUsing of taper wedge is easier than shim plate.Hand grinded ms plates for extra packing plates should not be used.Torque wrench should be provided for tightening of foundation bolt.Taper wedges were deformed due to direct hammering .

SUGGESTION

CONCLUSION Alignment is the most important procedure done for efficient and effective running of turbine for a longer period of time.THANK YOU