Page 161 - Valve Selection Handbook

148 Valve Selection Handbook

Figure 4-9. Swing Check Valve with Steel Reinforced Rubber Disc, the Disc Being an
Integral Part of the Body Gasket. (Courtesy of Sounders Valve Company Limited.)

Figure 4-10. Double-Disc Swing Check Valve. (Courtesy of Mission Manufacturing Co.)

Operation of Check Valves

Check valves operate in a manner that avoids:

1. The formation of an excessively high surge pressure as a result of
the valve closing.
2. Rapid fluctuating movements of the valve closure member.