Fuente bibliográfica y base de datos extraída

1. PREPARATION

1.1 Check whether the barring gear assembly is dismantled, serviced and assembled again in position, ensuring the required clearances in the gear systems.

1.2 Check and ensure that bearings of the motor are lubricated.

1.3 Check and ensure that the motor is decoupled from the barring gear unit 1.4 Ensure all oil pipings are connected.

1.5 Start the starting oil pump and check whether lubrication oil pressure is between 1.0 to 1.2kg/cm at 40 to 50°C oil temperature,

1.6 Disconnect the lubrication-connected unions at barring gear and flush the piping. Fix back the oil piping.

1.7 Check the drain oil piping of each bearing for proper flow.

1.7. Lub. oil flow to bearing No. 1 should be checked by running the A.C. standby oil pump and closing the charging line of the governing system. This way only lub. oil will be flowing, through the drain. It should be ensured before hand that there is no leakage from the line taken as tap off from Brg. No.l supply line for oil supply to MOP seals techno motor shaft &: gear coupling lubrication, otherwise considerable quantity of oil will be bypass from Brg. No.l. Check that adequate quantity of oil is visible in the drain sight glass.

1.7.2 For checking whether adequate quantity of lub. oil is flowing to the generator bearings, stop the seal oil system and check whether adequate quantity of oil is flowing through the drain sight glass with BG disengaged condition.

1.7.3 For checking whether adequate quantity of seal oil is flowing to the generator scale, stop all lub. oil pumps and run the A.C. seal oil pump alone. Charge the seal oil system and observe if adequate quantity of oil is flowing if adequate quantity of oil is flowing through the drain sight glass. By these procedure adequate quantity of lub. oil to all the bearings and seal oil to the generator seals is ensured.

1.8 Check in the front bearing pedestal whether all lubrication oil connections were made properly.

1.9 Check whether the protection for cutting off the barring at lubrication oil pressure of 0.3 kg/cm is connected.

1.10 Check whether the limit switch installed for cutting off the supply to solenoid (intended for auto engaging) whenever barring gear engages and trips off the motor whenever the barring gear disengages is connected properly.

2. TRIAL RUN OF MOTOR

2.1 Arrange for the electrical connection to the barring gear motor and ensure the electrical soundness of the motor for energising.

2.2 Start the motor and check the directions of rotation of the motor. 2.3 If the direction of rotation is OK trial run the motor for 8 hours.

2.4 Stop the motor after 8 hours of operation.

3. PREPARATION FOR PUTTING THE BARRING GEAR IN OPERATION

3.1 Couple the motor with barring gear unit.

3.2 Keep the barring gear in disengaged condition.

3.3 Rotate the barring gear assembly with the rotating disc. in clockwise direction and check its freeness of the gear train.

3.4 Check whether lubrication oil pressure is normal. In case A.C. standby oil pump is running the charging line to gov. sys. should be open.

3.5 Check whether the return oil flow from all the bearings are normal.

3.6 Engage the barring gear with the turbine shaft by rotating disc. in clockwise direction and simultaneously pushing the engaging lever.

3.7 Check whether lubrication for barring gear assembly is proper during oil flushing.

3.8 Discharge the barring gear by rotating the disc. in anti-clockwise direction and check whether lubrication oil to barring gear cuts off automatically. 3.9 Try the auto engaging of the barring gear (Caution : Without giving supply to

barring gear motor by switching off the CB) by giving supply to engaging solenoid and simultaneously rotating the rotating disc by hand.

3.10 Check whether supply is cut-off for engaging solenoid as soon as the barring gear engages.

3.11 Disengage the barring gear by rotating the rotating disc. in anti--clockwise direction.

3.12 Check whether protection for tripping the barring gear when the lubrication oil pressure drops to 0.3kg/cm is available.

3.13 Check whether A.C. and D.C. emergency oil pump auto scheme is available.

3.14 Check whether bearing metal temperature, and seal oil system temperature recording instruments are in working condition.

3.15 Check whether local glass thermometer for measuring the drain oil temperature are placed in position.

3.16 Check that the turbovisory eccentricity measuring instruments is available and the direct reading dial gauge also fixed in bearing No.2 for eccentricity measurement. The seal interface pick up should be made ready and switched on before engaging the barring gear.

3.17 Check whether seal oil system is in service with proper oil pressure with compressed air filled. And also proper interlocks for the seal oil system is available.

3.18 Check whether oil inlet temperature to the bearings is ^0°C to 50°C. 3.19 Engage the barring gear manually.

3.20 Start the barring gear and note down the starting current and normal current.

rod/seal interference pick up.

3.22 Stop the barring gear. Note down the coasting down period. Start the B.G. again.

3.24 Start the barring gear motor after engaging the gear.

3.25 Watch the return oil temperature from oil bearings and from the generator seals also.

3.26 Note down the eccentricity value at the control room and at the bearing No.2 pedestal (dial gauge). It should be same at UCB and Brg. No.2.

3.27 Check once again at turbine glands and generator seals for the healthy condition. Measure the vibration at Barring Gear Pedestal and at bearing covers of worm shaft and meter.