General The NIBCO® bronze gate valve is specifically designed for main control of an automatic fire sprinkler system. Usually, it is employed to isolate an individual floor of a multi-floor building as the floor’s main control valve. Rising stem gate valves are used when positive shutoff is required and a quick visual indicator of open/closed position is necessary. Overview Rising stem Solid wedge Screw-over bonnet Outside screw and yoke Class 125 threaded female end connections Dezincification resistant FM Approved