1. UPVC LINE LEAKAGERECTIFICATIONMUHAMMAD REHAN KHANMAINTENANCE ENGINEER

2. RAW WATER LINE PROFILING 3. RAW WATER LINE IN BRIEFThis line was installed and commissioned inyear 2008 by Procon EngineeringTotal length of the line is 5.95km and gradientis 31m from Sihpon-9 till Port Qasim reservoir.After Port Qasim reservoir, another CarbonSteel piping of 11 km is installed up till EPCLsite.A strainer was installed just after the Siphon-9point.There are total 7 Auto Vent Valves installed onthis line for venting and breathing of airautomatically. 4. VENT VALVE WORKING PRINCIPLE 5. TYPES OF VENT VALVES INSTALLED 6. PM OF VENT VALVES PM on Two monthly basis Cleaning of balls and internals Cleaning and greasing of stud bolts Operations Area Engineer verifies the activity 7. RAW WATER LINE STRAINERStrainerIsolation Valve Cleaning is done on need basis Cleaning of balls and internals Cleaning and greasing of stud bolts Operations Area Engineer verifies the activity 8. RAW WATER LINE LEAKAGE RECTIFICATIONThe leakage rectification activity is contracted out to Procon Engineering. However,providing material for leakage repair and ensuring safety and timeliness of the activity is theresponsibility of EPCL maintenance department.This activity is conducted in day and night shift and one designated maintenance supervisoris must to present all the time for coordination and providing leakage repair materialwhenever required.Work Permit is required to conduct any maintenance activity on raw water line.In case of any leakage, Contractor is formally informed through planning section and theactivity is planned in coordination with Utility Operations section.Following spares are present in EPCL warehouse which are used in leakage repair activityS # Item Description Qty. required for one leakage Item Code1 20 UPVC Pipe 6m 1403.0522.00042 Rubber Seal 2m 1403.0522.00023 Gibault Couplar 1 1403.0522.00034 Square Ring gasket 7m 2600.0243.0001 9. MAINTENANCE ACTIVITYJOB METHOD STATEMENTSince this is an underground piping,any leakage of raw water can onlybe identified when water flows out.The flow of water can be examinedto guess the extent and location ofleakage. 10. MAINTENANCE ACTIVITYJOB METHOD STATEMENTContractor brings variousequipment like excavator,generator, hydraulic jack, aircompressor and miscellaneoustools and start excavation afterhanding over work permit. 11. MAINTENANCE ACTIVITYJOB METHOD STATEMENTDamaged portion of the UPVCpipe is cut up to the requiredlength. Cut pipe is removed bylifting it with the help ofexcavator. 12. MAINTENANCE ACTIVITYJOB METHOD STATEMENTNew UPVC pipe is shifted toground and is cut on requiredlength using angle grinders.Smooth surface is also preparedfor installation.After pipe joints preparations,flanges of gibault couplar areinstalled on plain end of thepipe.In parallel, hydraulic jack isinstalled at the rubber ring side.Also, rubber ring seal is installedinside the female joint 13. MAINTENANCE ACTIVITYJOB METHOD STATEMENTUsing excavator, new pipe isinstalled at the location suchthat there is a gap at gibaultcoupler side where as pipe isinserted on the rubber ring side.GIBAULT COUPLAR 14. MAINTENANCE ACTIVITYJOB METHOD STATEMENTEnsure proper alignment of thepipe such that there should beno bending in the pipe length. 15. MAINTENANCE ACTIVITYJOB METHOD STATEMENTHydraulic jack is installed on therubber ring side of the pipe toinsert the new pipe and ensurethe rubber ring sealing betweenmale and female joints.Check the alignment of the pipeagain after installing rubber seal. 16. MAINTENANCE ACTIVITYJOB METHOD STATEMENTNow the square ring gasket iscut as per the gibault flangegroove size and is installed withthe help of ELFY. Ensure that thesquare ring gasket is cut andinstalled at an angle of 45 degreeto ensure complete sealing ofthe joint. 17. MAINTENANCE ACTIVITYJOB METHOD STATEMENTAfter installing the gibault flange gaskets, flanges are tightened with stud bolts.Before taking the line into service, backfilling beneath the new pipe is ensured otherwiseit will be burst again. After taking the line into service, inspection is performed to verifythat there is no leakage from any joint. Rectification and tightening is done accordingly.After inspection, back filling is done 18. THANK YOUMUHAMMAD REHAN KHANMAINTENANCE ENGINEER