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Plastic True Union Air Release Valve

Hayward, Industrial, Flow Control Systems

Plastic, True Union, Air Release Valve, HaywardTank, Container and Vessel Protection: Emptying or filling a closed tank requires that it be vented to allow the passage of air into or out of the tank in order to prevent damage to the tank. This is the function of Hayward's True Union Air Release Valve. It prevents overflow of the process fluid as a tank is being filled while allowing air to escape, minimizing the risk of the tank expanding as the result of compressing trapped air.

Automatic Operation: The Hayward True Union Air Release Valve operates without the need for any adjustments or settings. As the liquid in the tank rises to the valve level, the ball floats against the elastomer seat, automatically preventing unwanted flow out to the tank. When the liquid level falls below that of the valve, gravity opens the valve to allow air into the tank, eliminating the risk of the tank collapsing from vacuum pressure. The valve will vent a tank with flows in excess of 150 gpm. This is the equivalent of a 3 inch fill line flowing at up to 10 feet per second. For tank installations that use a 4 inch or 6 inch fill line, two air release valves can be used.

Easy Installation: The valve is supplied with both threaded and socket end connections in order to accommodate most applications. A screen cover is also included.

True Union Design: This permits easy removal from a piping system without breaking down piping connections. Just unscrew the assembly nut and lift the valve body out of the line. Maintenance could not be easier.

No Corrosion Failures: The all plastic construction means the valve will never fail, jam, stick, or freeze in position because of rust or corrosion. And they will not contaminate sensitive fluids that come into contact with them.


  • Reliable Tank Air Venting

  • Prevents Tank Overflow

  • Hollow, Floating Ball Design

  • Closes at 0 psi

  • Viton® or EPDM Seals

  • Standard Screen

  • Two Year Warranty

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About Us

Metex Corporation Limited has been providing superior products and services to the process control, chemical treatment, waste water, industrial and manufacturing industries for over 25 years. It is our goal to continually provide our customers with the best possible equipment, technology, and service.


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