Gate valves are generally used in systems where low flow resistance for a fully open valve is desired and there is no need to throttle the flow.
Globe valves are used in systems where good throttling characteristics and low seat leakage are desired and a relatively high head loss in an open valve is acceptable.
Ball valves allow quick, quarter turn on-off operation and have poor throttling characteristics.
Plug valves are often used to direct flow between several different ports through use of a single valve.
Diaphragm valves and pinch valves are used in systems where it is desirable for the entire operating mechanism to be completely isolated from the fluid.
Butterfly valves provide significant advantages over other valve designs in weight, space, and cost for large valve applications.
Check valves automatically open to allow flow in one direction and seat to prevent flow in the reverse direction.
A stop check valve is a combination of a lift check valve and a globe valve and incorporates the characteristics of both.
Safety/relief valves are used to provide automatic over-pressurization protection for a system.