Square gate, which is used in water project, is composed of gate, body, stem and actuator. Sealing principle is that rubber which is installed in the surface of gate and inner of body (welding into channel steel) .This kind of valve is cast iron valve and is single way to prevent water.  It's used in swage, water pool to control water's level. With simple structure, simple process, light weight, convenience install, it's wildly used in water conservancy .According to customers' requirements, it can be equipped with manual , pneumatic , electric and electro-hydraulic actuators etc, to control .