The distinction of Gate valve &Ball Valve and Butterfly Valve

Gate valve: the body Wedge plate and the direction of medium activity is vertical;  Flat lift to achieve open and close.  

Features: Good Air-tightness, Small fluid resistance,Small opening and closing force, widely used, also has a fixed conditioning flow performance, usually suitable for large diameter pipelines.
Ball valve: the use of a ball in the middle of the hole for the spool; The valve is opened and closed by rotating the ball.  

Features: The structure is simpler than the gate valve, the volume is small, the fluid resistance is small, can replace the role of gate valve.
Disc valve: the opening and closing part is a disc shaped valve with a fixed shaft rotating around the valve body.  

Features: Simple structure, small size, light weight, suitable for making large diameter valve.  Due to the sealing structure and material problems, so it is only used for low pressure, for conveying water, air, gas and other media!