Troubleshooting a Repeatedly Tripping Motor Operated Valve
A motor-operated valve was repeatedly tripping during operation from a particular system condition. The actuator torque setting had already been increased, but the problem returned. Initial hypotheses included: Valve mechanical restriction Damaged valve internals Insufficient actuator torque Excessive differential pressure Incorrect limit-switch setting Faulty limit-switch mechanism Actuator or valve coupling problem The valve was dismantled and inspected. The suspected internal damage was not found. The investigation then moved toward the actuator and limit-switch mechanism. ...