They are set up on pipelines as isolating valves | Forum

Gate valves are widespread for all sorts of applications and they are suitable for both above-ground and underground installation view more. Not least for underground installations, it's paramount to decide on the right sort of valve to protect yourself from high replacement costs.

Gate valves are equipped for fully open or fully closed service. They are set up on pipelines as isolating valves, and must not be used as being a control or regulating valves.Operation of your gate valve is finished doing an either clockwise to shut (CTC) or clockwise to start (CTO) rotating motion in the stem. When operating the valve stem, the gate moves up- or downwards about the threaded part in the stem.

The forms of gate valves might be divided into wedge disc gate valves and parallel disc gate valves based on the sealing surface configuration. Wedge disc gate valves is usually further separated into: single gate, double disc and elastic disc; parallel disc gate valves might be Divided into single disc type and double disc type. According to the thread position on the valve stem, it is usually divided into rising-stem gate valve and non rising-stem gate valve.

Installation and repair off rising-stem gate valve:
Handwheels, handles and transmission mechanisms will not be allowed to be utilized for lifting, and collisions are strictly prohibited.The double disc gate valve needs to be installed vertically (which is, the valve stem influences vertical position along with the handwheel is in the top).The gate valve using a bypass valve needs to be opened before opening (to balance the stress difference between the inlet and outlet reducing the opening force).The gate valve with transmission mechanism must be installed based on the product manual.

As the gate or wedge must travel throughout the entire cross-section on the valve bore, the general height of gate valve is larger rather than a ball valve that is a quarter turn valve and doesn't require vertical movement on the stem.

Gate valves are supplied with renewable seats that are usually hard to change out in-situ.
The valve flow characteristics of gate valve may cause high velocity of flow that occur for longer duration whilst the opening or closing the valve caused by slow movement of wedge or gate ball valve . High velocities could cause erosion of seat along with the disc thereby decreasing the design life on the valve. This condition can also be referred to as “wire drawing” effect.