Basic types of Valves

• Ball valve, for on/off control without pressure drop, and ideal for quick shut-off since a 90º 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.

3 Hastelloy check valves

• 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.

Stainless steel gate valve

• 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 Relief Valves
• Sampling valves