standards / manuals / guidelines for small hydro development - AHEC

5. Shaft Gland Seal and Air Seal:i) Check the condition of rubbing surface of sealing rings. In case founddamaged change the same.ii) Check pipe lines and piping joints for any leakage if any, attend the same.6. Emergency Slide Valve:i) Check the functioning of emergency slide valve and the condition of innersurfaces.ii) Swift return of the valve in its original position after emergency operationshould also be checked.7. Centralised Grease Lubrication System:i) Check satisfactory working of CGLS system.ii) Attend wherever fault is located.8. OPU:i) Check and attend leakage from any valve or flanged joints etc.ii) Provide proper lubrication to the bearings of pump motor.iii) Check filter and repair, if required.iv) Clean oil sump, refill with centrifuged oil.v) Check setting of the float relays for proper sequence of operation of pumps.9. Oil Headeri) Measure clearances of upper and lower bushes, if found increased get thebushes replaced.ii)iii)Clean the oil bath.Check the rubber cord fixed below the guide to check any oil dipping on theexciter winding.10. Oil Leakage Unit:i) Check satisfactory working on Auto as well as manual.ii) Clean the tank.iii) Check the pipeline joints and valve for leakage, attend wherever necessary.11. Oil Cooling Unit:i) Check all the oil and water pipe lines for leakage and attend if necessary.ii) Check satisfactory working of all cooling unit.12. Governor Mechanical Cabinet:i) Check filter and throttle if found damaged replace the same.ii) Attend leakage of oil through pipe line joints and valves.iii) Check auto rod setting, if found disturbed; set the same.iv) Alignment of feed back wire rope pulleys.4.1.5 Capital Maintenance of Hydro TurbineOverhauling or capital maintenance of hydro set is usually recommended after about 10 yearsof operation services. The whole unit is to be stripped off during capital maintenance and allthe defective/worn out parts/components repaired /replaced with new ones. Then the unitrecommissioned as per originally established commissioning practice of the power station.After capital maintenance the unit are subjected to all periodic maintenance exercise outlinedabove before it reach the next cycle of capital maintenance.Following check are to be exercised during capital maintenance of a hydro set:1. Turbine Bearing:AHEC/MNRE/SHP Standards/ E&M Works – Guidelines for Operation and Maintenance of Small Hydropower Station 20