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
• Clapper valve, Used in appliances like the Siamese fire appliance to allow only 1 hose to connected instead of two (the clapper valve blocks the other side from leaking out.
• 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 and control.
• 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, commonly used in piston engines to regulate the fuel mixture intake and exhaust
• Spool valve, for hydraulic control
• Thermal expansion valve, used in refrigeration and air conditioning systems.
• Pressure Reducing Valve
• Sampling valves
• Safety valve

Specific types

• Aspin valve: a cone-shaped metal part fitted to the cylinder head of an engine
• Ball cock: often used as a water level controller (cistern)
• Bibcock: provides a connection to a flexible hosepipe
• Blast valve: prevents rapid overpressuring in a fallout shelter or a bunker
• Boston valve: three-part two-port check valve used on inflatable boats, air mattresses, airbeds etc.; available in two sizes, normal and small
• Cock: colloquial term for a small valve or a stopcock
• Demand valve: on a diving regulator
• Double beat valve
• Double check valve
• Duckbill valve
• Flipper valve
• Flow control valve: an application which maintains a variable flow rate through the valve
• Heimlich valve: a specific one-way valve used on the end of chest drain tubes to treat a pneumothorax
• Foot valve: a check valve on the foot of a suction line to prevent backflow
• Four-way valve: was used to control the flow of steam to the cylinder of early double-acting steam engines
• Freeze seal/Freeze plug: in which freezing and melting the fluid creates and removes a plug of frozen material acting as the valve
• Gas pressure regulator regulates the flow and pressure of a gas
• Heart valve: regulates blood flow through the heart in many organisms
• Larner–Johnson Valve: needle control valve often in large sizes used in water supply systems
• Leaf valve: one-way valve consisting of a diagonal obstruction with an opening covered by a hinged flap
• Pilot valve: regulates flow or pressure to other valves
• Pinch valve, "beach ball valve": simple, single-part two-port check valve made from soft plastic and molded on to inflatable units such as beach balls, air mattresses, water wings; can be inflated by pump or by mouth.
• Plunger valve: To regulate flow while lowering the pressure
• Poppet valve and sleeve valve: commonly used in piston engines to regulate the fuel mixture intake and exhaust
• Pressure regulator or pressure reducing valve (PRV): reduces pressure to a preset level downstream of the valve
• Pressure sustaining valve, or back-pressure regulator: maintains pressure at a preset level upstream of the valve
• Presta and Schrader valves are used to hold the air in bicycle tires
• Reed valve: consists of two or more flexible materials pressed together along much of their length, but with the influx area open to allow one-way flow, much like a heart valve
• Regulator: used in SCUBA diving equipment and in gas cooking equipment to reduce the high pressure gas supply to a lower working pressure
• Rocker valve
• Rotolock valve
• Rotary valves and piston valves: parts of brass instruments used to change their pitch
• Rupture disc: a one time use replaceable valve for rapid pressure relief, used to protect piping systems from excessive pressure or vacuum; more reliable than a safety valve
• Saddle valve: where allowed, is used to tap a pipe for a low-flow need
• Safety valve or relief valve: operates automatically at a set differential pressure to correct a potentially dangerous situation, typically over-pressure
• Schrader valve: used to hold the air inside automobile tires
• Solenoid valve: an electrically controlled hydraulic or pneumatic valve
• Stopcock: restricts or isolates flow through a pipe
• Swirl valve: A specially designed Joule-Thompson pressure reduction/expansion valve imparting a centrifugal force upon the discharge stream for improving gas–liquid phase separation
• Tap (British English), faucet (American English): the common name for a valve used in homes to regulate water flow
• Tesla valve: A form of check valve with no moving parts, invented by Nikola Tesla for use with fluids.
• Thermal expansion valve, used in air conditioning and refrigeration systems.
• Thermostatic mixing valve
• Thermostatic radiator valve
• Trap primer: sometimes include other types of valves, or are valves themselves
• Vacuum breaker valve: prevents the back-siphonage of contaminated water into pressurized drinkable water supplies