u.s. carbon steel gate valve -ag捕鱼王app官网

gate valve, is a valve that opens by lifting a round or rectangular gate/wedge out of the path of the fluid. the distinct feature of a gate valve is the sealing surfaces between the gate and seats are planar, so gate valves are often used when a straight-line flow of fluid and minimum restriction is asked. gate valves are characterized as having either a rising or a non-rising stem. rising stems provide a visual indication of valve position because the stem is attached to the gate such that the gate and stem rise and lower together as the valve is operated. non-rising stem valves may have a pointer threaded onto the upper end of the stem to indicate valve position. non-rising stems are used underground or where vertical space is limited.