How does a steam control valve work?

Steam is supplied at a specific pressure to the upstream side of the control valve through which it passes to a heat exchanger, also operating at a specific pressure. Steam passes through the control valve and into the steam space of the equipment where it comes into contact with the heat transfer surfaces.

What is the function of control valve?

A control valve is a valve used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller. This enables the direct control of flow rate and the consequential control of process quantities such as pressure, temperature, and liquid level.

What are the functions of control valve components?

A valve controls system or process fluid flow and pressure by performing any of the following functions:

  • Stopping and starting fluid flow.
  • Varying (throttling) the amount of fluid flow.
  • Controlling the direction of fluid flow.
  • Regulating downstream system or process pressure.
  • Relieving component or piping over pressure.

How do you control steam pressure?

Steam pressure and temperature are related, and hence temperature is automatically controlled through the control of steam pressure. The reduction of steam pressure is also related to the required plant safety. Steam pressure can be controlled by using Steam Control Valve.

Which valve is used for steam control?

As globe valves excel at regulating flow, they are the most commonly used control valve for modulating purposes. Because of this, globe valves are often our go-to recommendation for steam applications.

Where are control valves used?

Control valves are used in many processes to control flow, pressure, temperature or other variables. The type of valve used will depend on the size of the pipe, the overall pressure that the system operates, the flowing media, process conditions, and other factors.

What is the working principle of a valve?

The working principle of control valve is opening or closing internal passages in order to regulate the flow of a liquid or gas. Control valves are part of a control loop that controls a process. Control valves adjust internal openings in response to instructions from the controller.

How do valves reduce pressure?

CONTROL VALVES On the bottom of the diaphragm, the outlet pressure of the valve forces the diaphragm upward to shut the valve. When the outlet pressure drops below the set point of the valve, the spring pressure overcomes the outlet pressure and forces the valve stem downward, opening the valve.

How do you control steam temperature?

Steam temperature is normally controlled by spraying water into the steam between the first and second-stage superheater to cool it down. Water injection is done in a device called an attemperator or desuperheater.