Air Pumping Ltd, diaphragm pump distributor

Ingersoll Rand / ARO

About Ingersoll Rand / ARO


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Ingersoll Rand / ARO Air Valve Technology

Ingersoll Rand / ARO

ARO Air Valve Patented Technology

"Unbalanced" Air Valve

As relevant today as the day it came to the market, Aro is still the sole owner of the technology and the title: 'Unstallable'. Aro uses no magnets, springs, re-set buttons, or other secondary actuators to insure pump shifting - only air.

Aro's patented "unbalanced" major air valve has constant air pressure applied to its small end. This assures that the pump resets. Competitive designs lose their signal during every shift, making them vulnerable to stalling.

To reverse the valve, air pressure is supplied to the larger end of the valve, allowing the valve to shift - note that constant air pressure continues to be applied to the small end.

ARO's "Unbalanced" air valve design makes this, and all of ARO's Diaphragm Pumps "Unstallable". Because the unbalanced valve cannot settle in a neutral position when the pump is shut down, it cannot become stuck, requiring the operator to hammer on the pump in order to start pumping again.

Anti Ice Air Valve (Below)

Following closely on the heels of the pump stall-out is the infamous freezing problems inherent in most diaphragm pumps. At Aro, the ice age has been over since the introduction of our unique, enlarged "Quick Dump™" patented air exhaust valve, which diverts air exhaust from critical, ice-prone passages. Available on the Aro 2" (Ball & Flap) and 3" Models.

When the main valve opens [Fig 1.] and pressurizes the diaphragm air chamber, the QuickDump™ operates like a normal air passage and admits air into the diaphragm's air chamber. When the main air valve is ready to exhaust [Fig 2.], the QuickDump™ diverts all of the cold/wet exhaust air coming from the diaphragm air chamber away from the main air valve, avoiding the ice formation in the critical valve passages.

Fig 1.
Fig 2.

For Safety, Reliability and Ease of Assembly: Bolted is Better

ARO Diaphragm Pumps feature bolted construction to avoid the proven problems created by clamp-band type pump fasteners. These included material spills and leaks, bolt loosening and breakage due to poor joint.

An Air Valve that Forgives and Forgets

ARO's major air valve requires no added lubrication and the "wiping" action of the seals makes it extremely forgiving of contaminated compressed air supplies.

The close fittings air valve designs used on competitive pumps allow air to by-pass continually - wasting air - even when not pumping!

Lost Air is no Bargain

In many processes, ENERGY is the second highest cost after manpower. If your diaphragm pumps are not ARO Diaphragm pumps, chances are their air valves are blowing out perfectly good air to atmosphere, at no small expense. And this is not intermittent, this is whenever and wherever these pumps are operating.