According to the function and use, the gate valve has small flow resistance and good sealing performance. Because the flow direction of the gate valve plate and the medium is vertical Angle, if the gate valve is not in place in the valve plate switch, the medium scour the valve plate to make the valve plate vibrate, easy to damage the seal of the gate valve. 

Butterfly valve also known as flap valve is a kind of regulating valve with simple structure. Butterfly valve that can be used for on-off control of low-pressure pipeline medium refers to the closing part.( Disc or Plate) is disc. Shaft rotation around the valve to open and close valve which can be widely use to control Air, Water, Steam, various of corrosive medium, Mud, Oil, Liquid metal and radioactive medium..It mainly plays a cutting and throttling role in the pipeline. Butterfly valve opening and closing parts calls Disc, in the valve body around its own axis rotation, so at to achieve the purpose of opening and closing regulating.

The butterfly plate is driven by the Stem. If it turns 90°, it can be opened and closed once to change the deflection angle of the butterfly plate and the flow of the medium can be controlled.

Working condition and medium. Butterfly valve is suitable for conveying various corrosive and non-corrosive fluids in engineering systems such as producer, Coal Gas, Natural Gas, Liquefied petroleum Gas, Hot Air, Cold Air, Chemical smelting and power generation environmental protection, building water supply and drainage etc. On the pipeline of the medium, it is used to regulate and cut off the flow of the medium.

Gate valve is an opening and closing gate.The movement direction of the gate is perpendicular to the direction of the fluid, the gate valve can only be fully opened and fully closed.

The sealing face can be sealed by medium pressure alone when the gate valve is closed. That is only reply on medium pressure to seal the sealing face of the gate to the other side of the seat to ensure the sealing face. This is self-sealing. Most gate valves are forced sealed. When the valve is closed, it is necessary to rely on external force to pressure the gate and seat to ensure the sealing surface sealing.