CALIBRATE AIR / GAS ACTUATED BALL VALVE

*note: this is the sample document for the related job only

*author: theprocedure@engineer.com

THE FUNCTIONAL TEST MUST BE DONE IN THE PRESENCE AND ASSISTANCE OF OPERATION PERSONNELS.

1) ACTUATOR

a. INSPECT FOR CORROSION AND DAMAGE.

b. CHECK TIGHTNESS OF LOCK NUTS ON STROKE ADJUSTING RODS.

 - ENSURE NOT TO CHANGE LENGTH OF STROKE.

c. CHECK THAT THE BREATHER ON THE END OF THE RETURN SPRING CYLINDER IS NOT

    BLOCKED.

d. CHECK OPERATION OF ACTUATOR AS FOLLOWS:

     NOTE:

     BEFORE OPERATING THE ACTUATOR ENSURE THAT THE PROCESS IS NOT IN

     OPERATION AND THAT IS IN SAFE TO OPEN AND CLOSE THE BALL VALVE.

        i)  CHECK THAT THE AIR/GAS PRESSURE LINE TO THE ACTUATOR IS DE-PRESSURISED

            AND DISCONNECT AT ACTUATOR.

       ii)  CONNECT CONTROLLABLE AIR/GAS SUPPLY OF 0 TO 7 BARG TO THE ACTUATOR.

       iii) RAISE AND LOWER THE AIR/GAS PRESSURE TO THE ACTUATOR A FEW TIMES. THE

            PISTON STROKE STOPS SHOULD PREVENT HAMMERING OF THE VALVE STOPS.

    e. IF THE PISTON STOPS REQUIRE  ADJUSTMENT PROCEED AS FOLLOWS :

       i)   ALLOW THE RETURN SPRING TO OPERATE THE VALVE.

       ii)  CHECK THAT THE VALVE STEM BRACKET JUST MATES WITH THE STOP BY

            SCREWING  IN THE PISTON STOP ROD UNTIL THE BRACKET.

            JUST LIFT OFF THE STOP AND LOCK THE ADJUSTMENT ROD BY LOCK NUT.

       iii) APPLY AIR/GAS PRESSURE SLOWLY TO THE CYLINDER AND ALLOW THE VALVE

           TO BE DRIVEN FULLY TO  OTHER  POSITION.

       iv)  CHECK THAT THE PISTON STOP ROD PREVENTS THE VALVE STOP BRACKET

             FROM STRIKING THE STOP SCREW. IF NECESSARY , ADJUST THE STROKE BY THE

             ADJUSTMENT ROD LOCATED AT THE END OF THE RETURN SPRING HOUSING.

        v)  CYCLE THE VALVE OPEN  AND CLOSED SEVERAL TIMES TO STABILISE THE

             STROKE ADJUSTMENT AND RECHECK THE STROKE.

    f. WHILST CARRYING OUT THE ACTUATOR OPERATIONAL CHECKS AS PER ITEM d . IF

       THE AIR/GAS  ESCAPES FROM THE VENT IN THE SPRING HOUSING WHEN THE PISTON

       IS STATIONARY,THE PISTON REQUIRES REPLACEMENT .

    g. ENSURE THAT THE LUBRICATOR IS 3/4 FULL OF CLEAN OIL.

    h. RECONNECT THE  AIR/GAS OPERATING LINE .

    i. CHECK FOR AIR/GAS LEAKAGE , WHEN THE SYSTEM IS IN PRODUCTION

2.  BALL VALVE
    a. INSPECT FOR CORROSION AND DAMAGE.
    b. CHECK FOR LEAKS  AROUND THE VALVE WHILST IN NORMAL OPERATING
        CONDITIONS .
    c. IF THE VALVE IS LEAKING AROUND THE STEM , PROCEED TO TIGHTEN REPLACE
        STEM SEALS.
    d. CONTROL THE VALVE SEAT LEAKAGE , WHEN IT IS CLOSE.
       NOTES:
       i)   RECORD ANY ERROR / FAULTS IN MAINTENANCE SYSTEM.
       ii)  ALL THE DEFECTS MUST BE ELIMINATED AND THE VALVE SET IN
            SERVICES ARE FREE OF FAULTS.
       iii) CONSULT THE PRODUCT TECHNICAL MANUAL FOR MORE ADDITIONAL
            INFORMATION.
       iv)  LET THE SUPERVISOR  KNOW OF ANY ABNORMAL FINDINGS.