HOW TO MAINTENANCE OF PNEAUMATIC ACTUATOR

This Procedure is intended to provide guidance and instructions for carrying out the Calibration and maintenance of PNEAUMATIC ACTUATOR as per standard practices prescribed by OEM or General Industry best practices in safe manner while ensuring minimization of environmental impacts to the extent possible.

OTHER GENERAL INSTRUCTIONS FOR COMPLIANCE:

Work permit as should be secured and instructions provided in the permit should be complied. Where instructions are not clear, clarification should be requested from the concerned Supervisor. Work should only be commenced after ensuring that proper work environment is created (ex: Authorizations are secured, Isolations are confirmed, and required mobilization is done).

Access to Emergency evacuation and other emergency services such as medical and Fire protection shall be readily available and contact details are readily available concerned supervisor as well as contactor.

Access to drinking water, toilet and other essential infrastructure for both company and contract personel should be ensured.

WORK INSTRUCTION:

👉   Clean all pneumatic actuators/control valves and associated positioner.

👉   Confirm travel of actuator to physical 0% and desired 100% open.

👉   Ensure the healthiness of the pressure gauges associated with the actuator.

👉    Check for the leakage of the copper tubes or the SS tube.

👉      If any leakage is detected, isolate the instrument airline and attend the leakage.

👉    Flush the air line before Air Filter Regulator (AFR) and ensure there is no sign of presence of water inside, restore the instrument air and operate the valve to check.

👉     If problem further persists, check the outlet of AFR with test pressure gauge, whether it is giving a proper pressurized air as it has been set to give.

👉     If the outlet pressure of the AFR is not coinciding with the set value then flush the AFR/replace the AFR.

👉      Check the outlet of the positioner/ (I/P convertor) whether it is giving the pressure according to the command.

👉   Operate it through mA source.

👉   If the problem still persists, be ensured that the actuator is totally isolated electrically.

👉  Check for the tightness of the terminations.

👉   Check cable healthiness and continuity.

👉    Check that the link of the positioner is fully tight against the stem of the actuator.

👉   Re-calibrate the position transmitter if required.

    1.      To set the zero, close the valve completely and rotate the zero setting nut of position transmitter till it shows 0% in the screen.

    2.    To set the maximum, open the valve completely and rotate the span setting nut of position transmitter till it shows 100% in the screen.

👉    If 24 V DC is not available in particular feedback or command pair then:

👉    Check the respective fuses in DCS panel, if faulty (blinking red), change it.

👉      Ensure the proper plugging of the connectors to the card.

👉      Restore the actuator input power supply and instrument air.

👉     Ensure that the actuator has been set on remote & check the operation.

👉     After normalization, return the PTW.

CHECKS BEFORE RELEASE OF PERMIT

 a.     All T & P’s and manpower are removed.

b.      Clean the maintenance area properly.

c.       Normalize all isolation  & Return PTW.

HANDLING OF CONCESSIONS OR DEVIATIONS:

a.        In the Event of Any Changes or Deviation from Procedure are required due to Urgent business requirements or system/Equipment approval should be obtained from Head O&M.

b.        The report for the concerned task should clearly Captured the details of deviations and reason for the same.