Double Orifice Air Release Valve

Double Orifice Air Release Valve(also called triple-function combination air valve)is an integrated automatic pipeline accessory with two independent air passages inside one valve body,combining bulk air vent,vacuum break and continuous micro air release functions in a single unit.

Trapped air inside pressurized pipelines will cause flow blockage,pressure fluctuation,water hammer,higher energy consumption and even pipe deformation or rupture.This dual-orifice valve solves all air-related hazards automatically without electricity or manual operation,widely installed at pipeline peaks,pump outlets and long-distance transmission lines.

Working Principle

It relies on stainless steel floats and buoyancy to realize full-automatic three-stage operation:

Pipeline Filling(Large Orifice Function)

When filling empty pipes,massive air flows out rapidly through the large orifice.As water level rises,the large float lifts up and seals the big passage to avoid water spraying out.

Normal Pressurized Operation(Small Orifice Function)

Dissolved air separates out and gathers at pipeline high points during steady running.Tiny air bubbles continuously exhaust through the small orifice to eliminate air pockets and maintain stable flow.

Pipeline Draining/Pump Shutdown(Vacuum Protection)

If pumps stop or pipes drain,internal negative pressure forms instantly.The large float drops to open the main orifice,sucking external air into the pipe to balance pressure and prevent pipeline collapse or cracking caused by vacuum suction.

Core Features&Advantages

Dual independent orifice design,covers all pipeline working conditions(filling,running,draining)

Fully automatic float-driven structure,no power supply,zero manual maintenance in daily use

Effectively suppress water hammer,reduce pipeline abrasion and extend service life

Ductile iron body with fusion-bonded epoxy coating(≥250μm),anti-corrosion for clean water

Standard SS304 float&EPDM/NBR food-grade sealing,good tightness without leakage

Compact modular structure,easy disassembly for inspection and component replacement

Wide pressure range PN10/PN16,temperature adaptability-10℃~70℃

Compliant with ISO,CE,WRAS drinking water certification standards

Technical Specifications

Nominal Diameter:DN50~DN300(2"~12")

Pressure Class:PN10,PN16,PN25 optional

Connection Type:Flange end EN1092-2/ISO7005

Medium:Tap water,raw water,irrigation water,neutral industrial wastewater

Max Medium Temperature:70°C

Test Standard:BS EN 6755,hydraulic test at 1.5 times rated pressure

Main Application Scenarios

Municipal potable water supply&distribution pipelines

Long-distance water transmission mains

Agricultural irrigation&farm water delivery systems

Pump station discharge&suction pipelines

Sewage treatment&recycled water networks

District cooling/industrial circulating water systems

Plastic pipeline projects with high vacuum risk