Unit No.1 LP Heater No.4 Normal Level Control Valve Diaphragm Leak

Operation called to check control valve which only open 70% but feedback position is 100%

• By manual from DCS open the valve 0%– 100 % : ok
• Physical check from field has small leak at the diaphragm nut hole, try retighten the bolt but still leak from opposite side.
  
• Inform operation to raised defect, need to replace with the new diaphragm and calibrate the valve.
  

Follow up defect

Operation allows replacing the leak diaphragm. Get the new one from the store and replace the defect diaphragm. Calibrate and do stroke check. Everything back to normal operation and permit was cancelled.