Air Release Valve

MODERN Automatic Air Valves for Water Mains

  • Single Orifice Air Valve - Air relief during normal running
  • Single Orifice Air Valve - Air release /Suction during filling or draining
  • Dual Orifice Air Valve - Combination air valve
  • IS 14845 and AWWA C512
  • Anti Vacuum Valve

Cluster for large main

The presence of free air in pipeline can reduce the severity of water hammer considerably. Celerity(speed) of an elastic wave with, say 2% of air at a pressure head of 50m of water reduces celerity from about 1100m/s to 160 m/s for a typical pipe line. On the other hand air in a rising main, whether in solution or in bubble from can have number of ill effects.

  • Cavitation - The formation of vacuous cavities which subsequently rapidly collapse and erode the pump or pipe
  • Head loss - Accelerating water past air pockets formed in pipes, leading to head losses
  • Other forms may include surging, Corrosion, reduced pump efficiency, malfunctioning of valves or vibrations

A pipeline designer therefore has to factor in all the aforesaid, the critical level of permissible vacuum inside a pipeline to prevent collapse vis-a-vis the suction and discharge capacity of an air valve (curves on request) before deciding upon the type, size, spacing and location of these air valves.

Valve size 

For Mains size 


Upto 200ø 


225 - 350ø


400 - 500ø


600 - 900ø


1000 - 1200ø


  • Normally 10 bar rated, 16 bar or higher pressure on request.
  • Single Air Valve of size 1” as per IS: 14845 can be supplied, suitable for 100 NB mains.
  • Not recommended for sewage application.

For mains size larger than 1200 NB, it is recommended that a cluster of 2 or 3 air valves be used in one location

Single Air Valve

Double Air Valve

Kinetic Air Valve

Air Cushion Valve

Double jet

Tamper proof air valve