Check Valves
A check valve is installed in a pipeline to prevent backflow. A check valve is a one-way valve that allows flow in one direction but closes to protect the piping if the flow reverses. Water hammer may happen if the flow reverses and there is no check valve in place. Often, water hammer occurs with an extreme level of force, damaging pipelines or other components.
Check valves are used in various industries:
Pumps:
Many different types of pumps use check valves to function properly. The pumps that supply water to water slides also use check valves.
Industrial Processes:
Many fluid systems, such as those in chemical and power plants, and in many other industrial processes, use check valves. Check valves are used in aircraft and aerospace where high vibration, large temperature extremes, and corrosive fluids are present.
To avoid the mixing of the gases at the original source, a check valve is fitted on each of the independent gas streams. When several gases are combined into a single gas stream, check valves are frequently utilized.
Domestic use
A check valve called a backflow preventer is used to prevent contaminated water from re-entering the domestic water supply when a sanitary potable water supply is plumbed to an unsanitary system.
Check valves, also called gravity brakes, are used in domestic heating systems to prevent vertical convection, especially in combination with solar thermal installations.
Advantages of Check Valves
- Backflows are prevented
- Capable of surviving both high and low pressure
- Serves as a backup system and safety system at the same time.
- Self-actuating
- Swift and effective action
- Protect pumps and compressors from backflow.
- Minimize production losses and downtime
- Prevents water hammer
Disadvantages of Check Valves
Operating in pulsing systems has several drawbacks, including:
- Operating in a completely contained system makes it impossible to inspect whether the discs are open or closed;
- Internal parts cannot be checked; and
- Disks can become trapped in the open position.
- Water hammer; noise from slamming discs
