List of valves. Valves are quite diverse and may be classified into a number types.

Basic types

The inside of an extremely large butterfly valve
Duplex ball valve
Three check valves in corrosion-resistant Hastelloy
Stainless steel gate valve

Valves can be categorized into the following basic types:

  • Ball valve, for on/off control without pressure drop, and ideal for quick shut-off, since a 90° turn offers complete shut-off angle, compared to multiple turns required on most manual valves.
  • Butterfly valve, for flow regulation in large pipe diameters.
  • Ceramic Disc valve, used mainly in high duty cycle applications or on abrasive fluids. Ceramic disc can also provide Class IV seat leakage
  • Check valve or non-return valve, allows the fluid to pass in one direction only.
  • Choke valve, a valve that raises or lowers a solid cylinder which is placed around or inside another cylinder which has holes or slots. Used for high pressure drops found in oil and gas wellheads.
  • Diaphragm valve, which controls flow by a movement of a diaphragm. Upstream pressure, downstream pressure, or an external source (e.g., pneumatic, hydraulic, etc.) can be used to change the position of the diaphragm.
  • Gate valve, mainly for on/off control, with low pressure drop.
  • Globe valve, good for regulating flow.
  • Knife valve, similar to a gate valve, but usually more compact. Often used for slurries or powders on/off control.
  • Needle valve for accurate flow control.
  • Pinch valve, for slurry flow regulation.
  • Piston valve, for regulating fluids that carry solids in suspension.
  • Plug valve, slim valve for on/off control but with some pressure drop.
  • Poppet valve
  • Spool valve, for hydraulic control
  • Thermal expansion valve, used in refrigeration and air conditioning systems.
  • Pressure Reducing Valve
  • Sampling valves
  • Safety valve

Specific types

In biology

Nature has developed an efficient valve, the sphincter, found in many animals including humans.