They are positioned in pipelines as isolating valves from aoaltwar's blog

Gate valves are widespread for all varieties of applications and therefore are suitable for both above-ground and underground installation view more. Not least for underground installations, it's paramount to find the right kind of valve to prevent high replacement costs.

Gate valves target fully open or fully closed service. They are set up in pipelines as isolating valves, and really should not be used as being a control or regulating valves.Operation of the gate valve is conducted doing an either clockwise to shut (CTC) or clockwise to spread out (CTO) rotating motion from the stem. When operating the valve stem, the gate moves up- or downwards around the threaded part with the stem.

The kinds of gate valves might be divided into wedge disc gate valves and parallel disc gate valves in accordance with the sealing surface configuration. Wedge disc gate valves may be further split into: single gate, double disc and elastic disc; parallel disc gate valves may be Divided into single disc type and double disc type. According to the thread position from the valve stem, it could be divided into rising-stem gate valve and non rising-stem gate valve.

Installation and upkeep of rising-stem gate valve:
Handwheels, handles and transmission mechanisms are certainly not allowed to be utilized for lifting, and collisions are strictly prohibited.The double disc gate valve ought to be installed vertically (that may be, the valve stem is with the vertical position as well as the handwheel is a the top).The gate valve that has a bypass valve needs to be opened before opening (to balance for most difference between the inlet and outlet minimizing the opening force).The gate valve with transmission mechanism really should be installed based on the product manual.

As the gate or wedge must travel throughout the entire cross-section from the valve bore, the general height of gate valve is larger over a ball valve that is a quarter turn valve and require vertical movement on the stem.

Gate valves are given with renewable seats that happen to be usually tricky to change out in-situ.
The valve flow characteristics of gate valve might cause high velocity of flow that occur for longer duration even though the opening or closing the valve as a result of slow movement of wedge or gate ball valve . High velocities might cause erosion of seat along with the disc thereby decreasing the design life with the valve. This condition is usually referred to as “wire drawing” effect.