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Chemical Engineering vocabulary · Process Control and Instrumentation

Control valve

Meaning in chemical engineering, with examples

nounCore term

In chemical engineering, control valve means: An automatic valve that opens and closes in small steps on a signal from a controller, so that flow, pressure, level or temperature stays at the setpoint.

In Turkish: kontrol vanası, kontrol valfi, ayar vanası

How it is used

The most common final control element. Engineers size control valves using Cv, choose fail-open or fail-closed action, and check percentage opening. Operators say a valve is '30% open', 'wide open' or 'sticking'.

Example sentences

  1. The control valve is 95% open, so we have almost no room to increase the flow.

  2. The steam control valve fails closed if instrument air is lost.

Common collocations

  • control valve opening
  • fail-closed control valve
  • size a control valve
  • sticking control valve
  • valveA device in a pipe that starts, stops or adjusts the flow of a fluid, either by hand or automatically.
  • setpointThe target value that a controller tries to hold, such as a temperature of 85 °C or a tank level of 60%.
  • PID controllerThe most common type of process controller. It sets its output from three terms: proportional (the present error), integral (past error) and derivative (how fast the error is changing).
  • control loopA set of parts that work together to hold one process variable at its setpoint: a sensor and transmitter, a controller and a final element such as a control valve.
  • P&IDShort for piping and instrumentation diagram: a detailed drawing of every pipe, valve, instrument, control loop and safety device in a unit.

More terms: Process Control and Instrumentation

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