Double Expanding Gate Valve

Double Expanding Gate Valve

Double expanding through conduit gate valve is one kind of bilateral forced sealing valve with the capability of protecting the sealing surface, this type of expanding through conduit gate valve can be widely installed onto pipelines and storate devices for oil products, natural gas and oil, and corrosive medium such as acid and alkali ect.

The two-piece gates are on the start and end position of moving process, because of changing of main gate and sub gate according to incline position making two sealing surface of two-piece gates bring closing and expanding action. These actions can realize effective sealing and protect the sealing surface during valve open. When fully opened, the pair inclines of the two-piece gates will be expanded till they are stick to the seats preventing medium and impurity from entering. During the process of opening and closing, the pair inclines of the two-piece gates will close to the two sides of valve ensuring the gates moving freely. When fully closed,the pair inclines of the two-piece gates will detach and making the two sides of gates closing to the sealing surface to enhance a perfect sealing. When the double expanding through conduit gate valve is fully opened or closed, the chamber isolates from medium completely, by this way, under an accident condition, open the empty valve and draining valve to relieve the pressure firstly, and then carry out the malfunction remove, drainage and packing replacement.