by Peter Smith (Author), R. W. Zappe (Author) Valves are the components in a fluid flow or pressure system that regulate either the flow or the pressure of the fluid. They are used extensively in the process industries, especially petrochemical. Though there are only four basic types of valves, there is an enormous number of different kinds of valves within each category, each one used for a specific purpose. No other book on the market analyzes the use, construction, and selection of valves in such a comprehensive manner. Number of Pages: 416 Dimensions: 1.08 x 9.44 x 6.22 IN Illustrated: Yes Publication Date: December 12, 2003