Valve Troubleshooting and Maintenance Resources
17 Jul
Control Valve Spare Parts: Types, Wear & Replacement
Control valve spare parts are not interchangeable items selected by a generic name or nominal valve size. The correct replacement must match the...
14 Jul
Control Valve Hunting: Causes, Diagnosis and Corrective Actions
Control valve hunting is sustained, unwanted oscillation of valve travel around the position demanded by the control loop. The process variable m...
14 Jul
Control Valve Deadband: Causes, Effects, Testing and Reduction
When controller output reverses direction, a control valve assembly may show no observable response until the signal crosses a finite input range...
11 Jul
Actuator Bench Set: Meaning, Bench Range and Adjustment
Actuator bench set is the loading-pressure range required to move a spring-and-diaphragm actuator from the point of initial stem movement to its...
10 Jul
Steam Control Valve Problems and Troubleshooting
Steam control valve problems usually show up as passing, slow travel, hunting, excessive pressure drop, noise, vibration, or a valve position tha...
08 Jul
Valve Positioner Calibration: Zero, Span and Travel Checks for Control Valves
A control valve can receive the correct 4-20 mA command and still stop short, overshoot, or hunt if the positioner, actuator air pressure and val...
