Plunger valve is the valve body, valve cover, stem, plunger, hole frame, seal ring, hand wheel and other components. When the hand wheel is rotated, the valve rod drives the plunger to reciprocate up and down in the middle of the hole frame to complete the valve opening and closing functions. In the valve plunger and the seal ring between the interference fit, by adjusting the gland flange bolts, the seal ring compression force generated by the lateral hole and the valve body and the outer cylindrical seal plunger to ensure that the valve Sealing, to eliminate internal and external leakage, while the valve opening torque is small, enabling the valve to quickly open and close. Plunger valve closed by a stainless steel plunger, the upper and lower two flexible ring and a metal frame composition, the sealing effect by the plunger and seal to achieve close, the plunger inserted in the two seals, the sealing area When the plunger valve is opened and closed, the plunger moves slowly in the seal ring with almost no wear on the contact surface. When the plunger is closed, the plunger is inserted into the lower seal ring to cut off the flow channel. When the plunger is opened, the plunger is detached from the lower seal Circle, but still hidden in the ring, keep isolated from the outside world, will not leak.