Check Valve, Valve Without Backflow Preventative Lever
Valve is a device that serves to regulate, direct or control a fluid flow. The fuller the flow of water in the pipe, the greater pressure will be generated. This will cause backflow, i.e. the flow of water will move opposite to the current of the path so that it can cause a leak in the pipe. However, there is no need to worry because the backflow phenomenon can be overcome by the selection and proper use of valves.
Check Valve is one type of valve that serves to keep the flow from experiencing backflow. Check Valve has a different way of working with the type of valve in general. If other valves use levers to regulate flow movement, it is different from the Check Valve which uses gravity and pressure from the flow to regulate the flow itself. Therefore, Check Valve is often used to prevent backflow in a series of piping systems.
When the flow moves in the appropriate direction, the Check Valve will let the flow pass through the disk or plug. However, if there is an opposite current in the flow, the plug will close immediately so as to prevent the backflow.
Check Valve has a variety of types and different functions, such as:
- Swing Check Valve
Swing Check Valve is the same size as pipe diameter, disk, or cross section. This type of valve is designed with a model hanging on the top and is usually paired with a Gate Valve. The workings of the Swing Check Valve are found in the movement of the disk, where the disc will open when the flow is in the appropriate current and will be closed in case of a backflow. The advantages of this type of Check Valve are the low maintenance costs, as well as the low risk of pressure loss. However, Swing Check Valves are not recommended for low pressure flow, as this type of valve has cross-sectional resistance that can cause leakage in fluid flow.
- Lift Check Valve
This type of valve has the same working principle as swing check valve, but in Lift Check Valve there is a cone-shaped plug located on a stand. When the flow goes to the inlet, the plug will be pushed by the pressure of the fluid flow that will go directly to the outlet side. If there is a backflow then the plug will be closed and the greater backflow pressure, then the tighter plug on the stand. This prevents the backflow from occurring for a long time. Lift Check Valves are commonly used in the industrial sector to prevent backflow from condensate to steam which can cause corrosion of steam turbines. Lift Check Valve can also be used for gas fluid applications due to its small leakage rate.
- Backwater Valve
Backwater Valve is a type of valve used as an underground sewerage system, while for housing usually use this type of valve in the bathroom of the house. When flooded, the waterways will be full and make the pressure even higher. Backwater Valve will help withstand the pressure to prevent the occurrence of backflow.
- Swing Type Wafer Check Valve
This type of valve has the same principle of cooperation with other Check Valves. Swing Type Wafer Check Valve can be used for small pipes and tubing with cone-shaped ends.
Based on the type of Check Valve above, the most commonly used are the type of Swing Check Valve and Lift Check Valve. Swing Check Valve type is usually paired with Gate Valve, while for Lift Check Valve is used by the manufacturer as Ball Check which replaces the function of Ball Valve. So, Check Valve is one solution that the flow of water in the pipe can still flow in one direction and avoid backflow. By choosing the right Check Valve, the rate of fluid flow will be more optimal.