TYPES OF VALVES
The following important information in this chapter is summarized below.
Types of Valves Summary
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
Ball valves allow quick, quarter turn on-off operation and have poor throttling
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 overpressurization protection for