Cast iron slide gates are used to control the flow of fluid through openings for seating or unseating head. With seating or face pressure, fluid exerts a force on the front of the gate. The pressure of the water forces the gate slide against the frame. In the design of a structure where cast iron slide gates are used, place the gate so that it will be subjected to a higher seating head whenever possible. When this is done, a lighter gate can be used, and is usually more watertight.
Unseating or back pressure is encountered when the depth of fluid is greater on the back side of the gate. Under these conditions, the fluid force pushes the slide away from the frame and the total force must be resisted by the wedging devices and assembly bolts of the gate. Therefore, gates are designed for considerably less back pressure than they are for face pressure. The possibility of leakage increases with the fluid pushing the slide away from its seating surfaces.
Features & Benefits
Premium quality; components are cast and mating surfaces are machined to very precise tolerances to meet the latest AWWA C560 requirements
Precision seating faces; cast iron gates have machined bronze or stainless surfaces to provide a precision seating face, low leakage rate and consistent sealing performance; mating surfaces on gate flanges and cast iron thimbles are also machined to ensure a precision installation