An air release valve offers a vital role in pressurized piping systems. Air trapped in the pipeline will naturally rise and collect at high points within the system. This trapped air can cause pump failures, faulty instrumentation readings, corrosion, flow issues, and water hammer or pressure surges. Unnecessary air in the pipeline also makes the pump work harder, ending in additional energy consumption.
Air Release Valve installed to automatically release the air when a pipeline is being filled and allow the air to enter the channel when it is being emptied. Additionally, the air valve releases any entrapped air that might accumulate at high points in the pipeline during normal operations. In the absence of ARV, accumulated air and vacuum can cause problems like pipe rupture, bursting, squeezing, etc. Thus, an air release valve must protect the pipelines and protect the metering devices, and control valves from damages
Water pipelines and sewer force mains are popular areas to find air-release valves. If correctly installed, you should see them at the peaks and high points of the system. Sometimes they might be slightly downstream or paired with a combination air/vacuum valve. Air release valves are ideal for any closed-loop or pressurized piping that can entrap air. Air release valves have small orifices when compared with other types of air valves. Therefore, they're best for applications with smaller volumes of air to exhaust.
• Stopping and starting the flow of water
• Throttling the flow of water
• Maintaining water flow in the right direction
Air release valves are also referred to as small orifice valves due to their smaller orifice size than vacuum valves. They are generally connected to a compounded hinged float mechanism versus a simple float seat operation in the vacuum valves. This is how air release valves get their hydro mechanical advantage to open/close and vent air under pressurized system operation.