The main objective of this paper is to discuss the valve and pipe characteristics which affect the reverse velocities and pressure surges at the check valves. It is presented a test method by which check valves can be dynamically tested for sudden closure due to reverse flow. It is point out the influence of valve design, flow coefficient, and friction of the reverse velocity. The information developed from the test method can then be used to predict the resulting upstream and downstream transients or pressure surges caused by a check valve closure for a given piping system and flow deceleration. The test method of this paper produces a relationship between the flow deceleration and the reverse velocity at which the check valve closes.
