Ball valve are quarter-turn, straight through flow valve that have a round closure element with matching rounded seats that permit uniform sealing stress.  Ball valve are used in situations where tight shut-off is required.  The type of seat can vary with the valve pressure rating and materials of construction.  Some valve seats are composed of single molded forms, while other seats with higher-pressure ratings often incorporate a trunnion design where each face of the ball is separately sealed.  They are wide duty valve, able to transfer gases, liquids and liquids with suspended solids (slurries).

In general, ball valve offer many advantages when contrasted with other valve types. They provide superior ease of operation and can maintain and regulate high volume, high pressure and high temperature flow.  Most ball valve offer rugged construction providing for a long service life, and a comparably low cost.  Additionally, the design of the regulating element allows the valve to function without the complications of side loads, typical of butterfly or globe valve, and the valve design permits inspection and repair of seats and seals without removing the valves’ body from the line.

Ball valve are available in a variety of body styles, including one-piece, two-piece, three-piece and flanged body construction.  Each of these ball valve forms offers specific advantages depending upon the requirements of the given application.  Similarly, they are designed using a wide variety of materials, as required by their application.  Common ball valve materials include brass, bronze, copper, cast iron, ductile iron, stainless and other steel types, metal alloys and plastics including PVC and CPVC.  It is best to consult with the manufacturer for the specific properties of the materials used in the valve, and how this relates to the applications that include type, concentration and temperature of the media being handled.