Gate Valve

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Gate Valve:


  • The gate valve is the most frequently used valve in piping systems.
  • It is a general service valve that is used primarily for on-off, non throttling applications.
  • Gate valve uses a wedge shaped disk or gate as the closure member operating perpendicular to the flow.
  • It is raised to open and lowered to close the valve.
  • As the disk closes, it fits tightly against the seat surfaces in the valve body. 
  • This valve is used fully opened or fully closed condition only.
  • It should not be used for throttling services with partly open condition, as the gate will vibrate and quickly becomes damaged.
  • Classification of gate valve is based on type of disk used, that is Solid wedge, Flexible wedge, Split wedge or Parallel disk.

Working Principle:



Gate valves consist of three major components: body, bonnet, and trim. The body is generally connected to the piping by means of flanged, screwed, or welded connections. The bonnet, containing the moving parts, is joined to the body, generally with bolts, to permit cleaning and maintenance. The valve trim consists of the stem, the gate, the wedge, or disc, and the seat rings.

The main operation mechanism is very simple. When the hand-wheel is turned, it rotates the stem, which is translated into the vertical movement of a gate via threads. They are considered multi-turn valves as it takes more than one 360° turn to fully open/close the valve. When the gate is lifted from the path of the flow, the valve opens and when it returns to its closed position, it seals the bore resulting in a full closure of the valve.
                  ***Video link of gate valve working***

Advantages of Gate Valve:

  • Gate valve provides good on/off or shutoff features.
  • Pressure drop during operation is very less.
  • Gate valves are bi-directional valves and can provide shut-off in either flow directions.
  • They are suitable for high pressure and temperature application and required less maintenance.
  • Gate valves tend to be slightly cheaper than ball valves of the same size and quality.

Disadvantage of Gate Valve:

  • It cannot be used to regulate or throttle the flow.
  • A gate valve is slow in operation and can not be quickly opened or closed. This is good also as it reduces the chance of hammering.
  • It is prone to vibration and noise in the partially open state.
  • It is more subject to seat and disk wear.
  • Gate valves require large space envelope for installation, operation, and maintenance.
  • Repairs, such as lapping and grinding, are generally more difficult to accomplish.
  • Some designs of gate valves are susceptible to thermal or pressure locking, depending upon the application.


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