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A flat gate valve is a sliding valve that closes a parallel gate. The closure may be a single shutter or a double shutter with a distraction mechanism in between. The pressing force of the gate to the valve seat is controlled by the medium pressure acting on the floating gate or the floating valve seat. If it is a double gate plate gate valve, then the two gates between the distraction mechanism can supplement this pressure. Flat gate valve by driving can be divided into manual flat gate valve, pneumatic flat gate valve and electric flat gate valve. According to the purpose and use occasions can be divided into a diversion orifice plate gate valve, no diversion orifice plate gate valve, oil field plate gate valve, pipeline flat gate valve and gas flat gate valve. This series of products adopt the new floating seal structure, which is suitable for the opening, closing and adjusting devices of control media such as oil and natural gas with pressure less than 15.0MPa and temperature from -29 ℃ to 121 ℃. The product is of novel design, Proper, rigorous testing, light operation, with strong corrosion resistance, wear resistance, erosion resistance, the oil industry is an ideal new equipment.

Structural characteristics and working principle
1, the use of floating seat, two-way opening and closing, reliable sealing, opening and closing flexible. 
2, the gate has a guide bar to give precision-oriented, while the sealing surface are sprayed carbide, erosion-resistant. 
3, the valve body carrying capacity is high, the channel is straight-through, fully open, and the gate diversion hole through and straight pipe similar to the flow resistance is small. Stem composite filler, multiple seals, making the seal reliable, small friction. 
4, closing the valve, turn the handwheel clockwise, the gate moved down to the bottom, due to the role of media pressure, the inlet seal seat toward the gate direction, the formation of a larger seal than the pressure, forming the first seal . At the same time, the gate pressure to the outlet seal seat, a double seal. 
5, due to the use of double seals, it can be changed without affecting the work of the pipeline wearing parts. This is our factory product priority over similar products at home and abroad an important feature. 
6, open the gate, turn the hand wheel counterclockwise, the gate up, diversion hole and channel hole through. With the rise of the gate, the through hole gradually increases to the limit position, the guide hole coincides with the passage hole, then fully open.