A gate valve is used for controlling the media flow by lowering and lifting the gate. The unique thing about Gate Valve is the unobstructed passageway it provides. It will induce minimal pressure loss. This will allow for a pig passage which is not possible in butterfly valves. Gate valves are available in various options including various sizes, temperature ratings, pressure ratings, and materials.
These valves are cheaper when compared with the ball valves. Gate valves can be either fully closed or fully open. Thus, they will act as isolating valves only. You can’t regulate the flow by using gate valves. You can also use automated gate valves however manual gate valve is more cost-effective.
Where are gate valves used?
Gate valves are used when free bore and minimum pressure loss is required. If the gate valve is open, then there will be no obstruction in the path. This will result in very low-pressure loss. The operation of the valve is done by using a threaded stem. Thus, it can be used as a multiturn valve. The slow operation will also prevent water hammer effects.
You can use it with various fluids. These valves are very durable and resistant to high temperatures and pressure.
Gate valve working principle
Gate valves are operated with the help of a handwheel, actuator, and a wrench. The wheel will be attached to the valve stem. It will transfer rotational energy. If you are opening the gate, then the rotation of the handwheel will turn the threads. Similarly, it will turn the threads when you are closing the gate. The energy will move the gate valve in an upward or downward direction. An extension spindle is also used in the underground gate valve installations. This will ensure that the valve can be operated without accessing it.
Gate valves are used in areas of the pipeline where we need a valve to be closed or open for a long period of time. Someone needs to manually between these two positions. Thus, the gate valve should remain in the same position for a long period of time. If you want the valve to be operated quite often, then you should go for a motorized gate valve.
Types of gate valve
Gate valves are of various types. You can check the entire list at https://linquip.com/industrial-directories/344/gate-valve. However, two very famous types are:
Wedge-shaped or parallel gate valves
Parallel gate valves feature a parallel-faced and flat gate. This is also known as a knife gate valve.
Wedge gate valves have a wedge-shaped gate. It has ribs on both sides. The wedge is used for transferring the axial loads and enabling frictionless movement. It is also used for preventing the wedge from rotating.
Wedge gate valves are heavily used in industry.
Resilient or Metal Seated gate valves
These wedge gate valves can have resilient or metal valves. Metal seated valves have a wedge slide towards the invert of the valve body. It is used for trapping the solids that are contained in the fluid. Thus, metal seated valves are preferred in water distribution systems.
Resilient seated gate valves are made of ductile iron. They provide a tight seal to the valve. You can use it for sealing around small solids.
Benefits of Gate Valve
Some of the main benefits of using gate valve are:
- They are cheaper when compared with other industrial valves.
- Pressure drop is very less during operations.
- You can use these valves as a bi-directional valve.
- They are good for high-temperature and pressure applications.
- They require less maintenance.
Conclusion
Gate valve is very popular in the industry. It is heavily used in water supply systems. You can use it as an isolation valve. If you are looking for a gate valve, then make sure that you are getting the manual version. There is no point in buying a motorized gate valve until you want to operate it regularly.