The PPT explains various faults, issues and problems that may surface during operation of steam turbines. The PPT also very well explains the action plan to tackle the pains taking issues of steam turbine. This also helps to enhance operating lifespan of steam turbine while reducing losses. This document can also be referred for troubleshooting of BHEL turbines.

1. TURBINE
OPERATION ISSUES
Presented By:
TAHOOR ALAM KHAN
Dy. Manager-Operations
RattanIndia Power Limited

2. EHA OIL SYSTEM
• Loss of EHA oil pressure resulting into closing of control valves & stop
valves due to any of the following reasons:
• Oil line leakage.
• Malfunctioning pump.
• Malfunctioning Pilot Valve or TSV.
• EHA filter chocking.

3. TURBINE BEARING ISSUES
• Rise in turbine bearing metal temperature due to excessive loading.
• Turbine bearing worn out due to higher MI contents in oil.
• In adequate lube oil pressure can cause insufficient lubrication of bearings.
• High moisture contents in MOT oil causing inadequate cooling of bearings.
• Hindrance in formation of oil film inside bearing due to changes in oil
quality.

4. TURBINE VIBRATIONS
• Sudden changes in turbine load.
• Wear & Tear of turbine bearings.
• Wear & Tear of thrust pads of thrust bearing.
• High difference in upper and lower casing temperatures.
• Damaged moving or stationary blades.
• Sudden changes in seal steam pressure or temperature.

5. HIGH TEMPERATURE ISSUES
• Due to issues with DMCW cooling water system, following issues by occur:
• Exciter hot air temperature increases.
• MOT lube oil temperature increase causing increase in turbine bearing temperatures.
• Generator cold gas temperature will increase due to inadequate cooling in hydrogen
coolers.

6. SEAL STEAM ISSUES
• Seal steam can cause issues in following ways:
• Reduction in seal steam pressure causing drop in condenser vacuum.
• Closure of seal steam supply valve or opening of leak off valve causing drop in seal
steam header pressure.
• Drop in seal steam inlet temperature below 280 deg. C causing closing of inlet valve.
• High seal steam pressure may causing leakage of seal steam into atmosphere and can
also result into increase in MOT moisture.

7. GEN COOLING VALVE ISSUE
• Due to malfunctioning of generator gas cooling valve, the cold gas
temperature will increase causing outage of unit.
• Malfunctioning may due to issues related to supply module or command
problem.

8. CONDENSER VACUUM
• Loss is vacuum can be due to any of the following reasons:
• Tripping of vacuum pump.
• Inadequate seal steam pressure.
• Malfunctioning of seal steam supply valve or leak-off valve.
• Tripping of CW pumps.
• Opening of Vacuum Breaker.

9. SEAL OIL SYSTEM
• Seal oil is provided to avoid hydrogen to escape from generator from clearances
between gen shaft and gen casing. But failure of seal oil system can result into unit
outage.
• Due failure in maintaining seal oil pressure due to any of the following reason,
hydrogen purging need to be done along with turbine tripping
• Tripping of AC seal oil pumps and DC seal oil pump failure to start.
• DPR malfunction.
• VOT level low.
• Leakage in seal oil carrying line.

10. MEASUREMENT ISSUES
• Issues with parameter measurement includes:
• False temperature of turbine bearing, cold gas temp, hot exciter air temp or HP exhaust
temperature.
• False axial shift of turbine.
• False vibrations of shaft or bearing.
• False lube oil pressure, seal oil pressure etc.
• False main steam temperature.
• Malfunctioning of turbine overspeed trip channel.

11. HPBP/LPBP SYSTEM
• Sudden opening of HPBP or LPBP system due to any of the following
reason:
• HPBP valve opening due to loss of pressure due to leakage or pump tripping.
• HPBP valves fail to open due to loss of vacuum.
• LPBP valves fail to open due to condenser wall temperature high.

12. THANK YOU