应用於水轮发电机组中的液压控制设备通常有液压阀、止回阀、溢流阀、安全阀、卸荷阀、控制阀及各种截止阀等。除了单独使用外往往同时需要几个具有不同功能的阀门组合使用。如油压装置供油泵出口就需要止回阀,安全阀,溢流阀、卸荷阀通过管路连接。不但所占体积大,而且如安全阀等单个元件动作不可靠,检修不方便,给电站运行造成麻烦。扦装阀的设计和应用,使液压设备发生了根本性的变化。象电 Hydraulic control equipment used in hydro-generating units usually has hydraulic valves, check valves, relief valves, safety valves, unloading valves, control valves and various globe valves. In addition to the separate use often requires several valves with different functions at the same time. Such as oil pressure pump outlet for export on the need for check valve, relief valve, relief valve, unloading valve through the pipeline connection. Not only occupy a large volume, but also as a single component such as safety valve action is not reliable, maintenance inconvenient, causing trouble to the power station operation. The design and application of the packing valve make the hydraulic equipment have undergone fundamental changes. Like electricity