D.J. Gongol and Associates, Inc. represents the exceptional "aiRFlex" air-actuated pinch valve from RF Valves. What makes them exceptional? Download the "aiRFlex" pinch valve bulletin or simply read on...

Pinch valves are utility players

Plug valves are used everywhere in wastewater service. They're heavy, clumsy, and prone to needing repairs. But they're all over the place. Pinch valves are an excellent choice for flow control and modulation in any kind of service involving solids, abrasives, or chemicals -- the kinds of conditions we often see in wastewater service.

Pinch valves don't have any moving parts in the flow path, so there's nothing to clog and nothing to leak. Plus, the pinching action is great for sealing around debris that doesn't want to move downstream.

The "aiRFlex" steps right in to replace plug valves

But conventional pinch valves are sometimes hard to apply because they are usually much longer (from face to face) than other valves. A long lay length makes the body heavier, too. The "aiRFlex" makes it easy to replace plug valves because it's the same length as a standard plug valve. RF Valve has engineered the rubber sleeve to be pinched shut in a tighter space without contracting out of the body. This means that any place you have a plug valve, you can replace it with an "aiRFlex". They'll fit without modifications, work better, and weigh less!

Get rid of moving parts

What makes a pinch valve a superior plug valve replacement?

Start with this: No moving parts in the flow path. The entire working mechanism for the valve is outside the body. The only thing the fluid encounters is the rubber sleeve. No plug, no stem, no bushings, no glands to leak. Just a smooth rubber surface.

What about that weight loss?

A lighter-weight valve is better for operators and easier on pipes. Consider this comparison: A typical 4" cast or ductile iron plug valve weighs more than 70 lbs. with a bare shaft, and more than 100 lbs. with an actuator mechanism attached. A 4" cast iron "aiRFlex" pinch valve weighs 37 lbs. -- half the weight! The bigger the valve, the more agony you're sparing the operators (maybe you!) in the future.

Make it easy to replace

Suppose you have a high-abrasion fluid, like grit slurry. When that flows past a plug valve, it wears down the internal parts. Ultimately, the working mechanism goes bad, and operators are stuck either tearing apart a heavy plug valve and replacing parts one by one, or they have to put in a whole new valve. It's never a quick operation, and it requires taking the pipeline out of service until the job is finished.

With the "aiRFlex", the entire rubber sleeve can be replaced without unbolting the lower valve body from the pipe. Remember, the rubber sleeve is the only thing that ever touches the fluid -- so if you can replace it with ease, you can minimize maintenance downtime while you're also reducing the need to do any maintenance in the first place.

What can a pinch valve handle?

The ultimate advantage to pinch valves is their flexibility -- in more than one sense. The pinch valve works where other valves can't because the flexible sleeve pinches around whatever fluid you're trying to handle.

  • Corrosive chemicals? No problem -- just choose the right rubberized elastomer for your application.

  • Solids in your flows? No problem -- because it's rubberized, the pinch valve sleeve closes tight around almost any solid. Mechanical valves can't do that.

  • Head losses important? No problem -- pinch valves often have significantly lower head losses than other kinds of valves, especially plug valves. No matter how much "efficiency" their manufacturers claim to offer, plug valves still create flow disruptions even when fully open. It's inevitable, because the plug has to go somewhere, and wherever that is, there are expansions and contractions and non-linear paths for the flow to follow. Pinch valves can give you comparatively precise flow controls at a minimum of friction loss.

Where can you find pinch valves in service?

  • Wastewater treatment plants use pinch valves wherever sludge flows need to be controlled. Because pinch valves use the rubber body of the valve itself to control the rate of flow, they keep all working parts out of the sludge. Pinch valves are also ideal for controlling the flow of grit.

  • Water treatment plants use pinch valves to control the flow of lime slurries and other thick-flowing fluids. Pinch valves are ideal for corrosive chemicals, because the only part of the valve in contact with the fluid is the rubber valve sleeve itself. RF Valve pinch valves are available in a wide range of materials, so there's a resilient option available for nearly every kind of chemical.

  • Food processors use pinch valves for weighing, filling, and processing systems. Pinch valves are extraordinarily versatile, making them ideal for controlling liquid flows as well as solids that behave like fluids.

  • Power plants find pinch valves useful for a wide range of applications, from flue gas desulfurization scrubbers to fly ash handling to controlling coal, coal oil, and ash slurries.

  • Mining industries use pinch valves for lime control, dust collection, slurry controls for thickening clarifiers, and leaching processes.

  • Chemical systems offer dozens of potential applications for pinch valves, including lime addition and pH control systems, control of dirty and viscous chemicals, pump isolation, and back-pressure systems.

Pinch valves from RF Valve can be an efficient and economical solution to many flow-control problems. Contact us for design assistance or quotes by using our request page and we'll be happy to assist you.

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