The poor opening and closing of the valve manifests itself as the valve cannot be opened or closed, and the valve cannot operate normally. The reasons are: the valve stem is rusted; the gate is stuck or the gate is rusted in the closed state for a long time; the gate is detached; the foreign matter is stuck in the sealing surface or the groove; In the above circumstances, repair and lubricate the transmission parts; repeatedly open and close the valve and hydraulically impact foreign bodies; replace the valve.