high performance check valve

What are you moving with the piston, fluid or gas? What is the composition of the fluid or gas; Inert, corrosive, etc.? How much pressure is involved?

What types of check valves have you tried? What types of material?

What is the system used for?

Please provide more info.

-John

As i see it you want the check valve to close on the power stroke of the cylinder and release when the reverse stroke is completed.

A piston pump usually has a valve on the outlet side to prevent a back flow. if this is the case the delivery side will maintain pressure and the check valve will stay closed unless pressure is leaking out.

a piston pump is a positive displacement pump and will keep on supplying pressure within its means. something in pump or system will eventually fail.

without the valve on the outlet side air will be drawn in and compressed until enough pressure to keep the valve closed.

What do you want or need to achieve?

Thank you VM for the reply: "the check valve will stay closed unless pressure is leaking out."

I am moving plain air in a heat pump with the piston.

"As i see it you want the check valve to close on the power stroke of the cylinder and release when the reverse stroke is completed." This is exactly correct!

In an internal combustion engine valves are opened by the camshaft and held closed by the valve springs. These valve seats can be modified for high performance purposes (lapped seats). This effect is my desired outcome.

In my heat pump, the piston deliberately bypasses air in a comtrolled manner and the air (fluid) is then recirculated as exhaust into a closed loop back through the check valve. I expect the compression ratio to be 2-3:1.

I need compression to raise the heat in the compression chamber. As a result of this objective I am using a check valve to maintain compression and to open to allow one way movement in the loop.

I was wondering if anyone had experience with normal hydraulic check valve seat performance at holding compressive forces of air - either with typical check valves, high performance valves or I will will need to create them.

Thanks again

Back in the 70's I had a Yamaha RD-350 2-stroke cafe racer which had a dual reed-valve plate behind the carbs. These were thin metal plates that flexed (the 'reeds') over a shaped port. If it were to leak it would have backfired through the carbs, which it never did. As to performance, the 2-stoke could easily spin up to 12,000 RPMs, which means that the Reeds opened and closed at 12,000 Hz, and it never failed. With the tuned expansion chambers, it was rated at 53 Horsepower, so these reeds were very strong.

My point being that maybe you can use some 2-stroke reed valves ... maybe get one on the cheap from a string trimmer or a chainsaw to experiment with.

"My point being that maybe you can use some 2-stroke reed valves ... maybe get one on the cheap from a string trimmer or a chainsaw to experiment with."

Many thanks to:The Gregg - I m on the scent to track it down. And many thanks to all you smart guys out there who take the time. CVS:)

For compressing air and gases by using reciprocating compressors, the discharge pipe line can be furnished with special damping check valve, to damp any pulsation, minimizing vibration, and avoiding disk knocking of conventional type swing check valve.

Most reciprocating refrigeration compressors use reed valves and these last for 20years plus. Many air compresors also use reeds others use poppets, metal is no problem. The valve plate from a compressor is easy to work with.

A/C COMPRESSOR CAN HOLD THE PRESSURE 130-150 CONSISTANTLY. MULTIPLE PISTON DESIGNS. ALUMINUM HOUSINGS AVAILABLE, FOR HEAT TRANSFER. REED VALVES SEEM VERY IDEAL.