What is a sluice valve
A gate valve or also known as a sluice gate valve, is a valve that employs a gate or wedge-shaped disc that slides perpendicular to the flow of fluid into or out of the pipeline. When the gate valve is opened, the gate valve’s disc is completely isolated from the flow. This effectively eliminates all opposition to flow. As a result, there is very little pressure drop as the fluid passes through the gate valve. Sluice gate valves are the most common type of valve used in process plants to handle slurries. These valves are either fully open or fully closed when in use. Sluice gate valves cannot be used for throttling because they lack accuracy. Get more details on sluice valve malaysia here.
How does a sluice valve work?
The sluice gate valve is operated by a lifting gate or wedge, allowing water to flow freely. The top end of the stem has a hand-operated wheel or a motor that raises and lowers the doors, while the bottom end has a circular or wedge gate to prevent water flow. Because it has a threaded stem, the valve must be turned several times to go from open to closed and vice versa to prevent water hammering.
There are 2 main types of spindle that are used to raise the gate of the sluice valve which are:
- Rising spindle type valve: A spindle or stem is connected to the gate in this type of valve. The spindle valve does not function by rotating with the handwheel while in operation, but rather raises with the spindle.
- Non-rising spindle type valve: The spindle is threaded in this type of valve design, and the gate is threaded internally where it is attached to the spindle. The valve stem does not raise from its position while operating, but rather rotates in its place to raise the gate using threads.
A sluice valve is typically the same size as the main valve, which can have a diameter of up to 300 mm. The size of the valve is roughly two-thirds the size of the main valves for larger diameters. The valves are housed in a valve chamber with caps or handwheels to control them. The valve can be opened in either a clockwise or counter-clockwise direction, as indicated at the spindle’s outer end.
Sluice gate valves are most often used to stop the flow of liquid and cannot function as a flow regulator. When the sluice valve is completely open, there is no obstruction in the flow path, resulting in very little flow resistance. When you move the gate, the size of the open flow path varies non-linearly. This indicates that the flow rate does not vary uniformly with stem travel. A partly open gate will vibrate due to the flow of fluid, depending on the structure. Sluice valves are frequently used for larger pipe diameters due to their simpler construction than other types of large valves. Friction may become an issue under high pressure.