Looking for Efficient Pneumatic Power...Help!

Contact:

ASTO Controls
106-A, 1st Floor, Trade Corner, Sakinaka Junction, Andheri(E)
Mumbai - 400 072, Maharashtra, (India)
Mobile : 9820077540
Phone. : +(91)-(22)-56944022/26506452
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E-mail: astocontrols@rediffmail.com

Quality products like :

• Pneumatic Products
• Fluid Power Products
• Hydraulic Products

Thanks. They're now in my file. But do they deal with motors too?

For Pneumatic Actuators look up Spirax/ TLV sites.

Andyhorning:

".... an ultra-high-efficiency system of very lightweight reversible motors, flow regulators, valves and low-input-power/high-pressure/torque pumps (~ 900 Watts/ 250 Nm paroxysmal input)."

Using the terms "ultra high efficiency" and pneumatic motors in the same breath is a bit of a stretch. Air motors are very useful, but in terms of overall system efficiency including the compressor, they are not efficient energy wise. And I have absolutely no idea what you mean by "... low-input-power/high-pressure/torque pumps (~ 900 Watts/ 250 Nm paroxysmal input)". Please be more specific: Define very lightweight, output rpm, and the overall application specs., etc.

Taking a guess, you are talking about a motor that will typically weigh in the range of 70-120 lbs with its gearbox (in other words: a gearmotor), will have a output shaft diameter of typically 1.25"-1.625" (because of the torque) .. you don't mention output RPMs. The lighter and smaller it is, (and with that torque it won't be too light or small) the less efficiency you can expect. In any case its silly of me to guess like this.

The rest of the system can all be standard parts ... for higher efficiency, you want to reduce the pressure drop by using larger regulators, valves, fittings etc, and placing the regulator/lubricator as close to the motors as possible, since for the same mass flow of air, you have less energy losses (pressure drops) at higher pressures, all other things being equal. It is analogous to transmitting electricity, where you run long lines at higher voltages, and have the final drop-down transformer as close to the load as practical.

The web is loaded with pneumatic information of all kinds, and from very many suppliers, but am I safe in assuming you have looked there?

I would search the web and contact suppliers and manufacturers of air motors and gearmotors. They have a wealth of information.

Please give us more specifics.

Greg

OK, yeah, I know. I was thinking in relative terms of efficiency, but Airpel's line of borosilicate-lined cylinders already fit one part of my requirements. On the other hand, what I'm looking for in terms of weight in a reversible motor may not yet be available. There are toy airplane motors (Air Hogs) that are a little like a mini-version of what I need to run up to 200 rpm one way and 50rpm in reverse. I like the idea of the "Quasiturbine" motors because you could use plastic extrusions to make inexpensive rotors, but I have no useful information on their efficiency relative to existing plastic piston motors (as used for food prep/medical industry uses).

All this will be a part of a fairly large moving assembly on which I need to keep mass to a minimum, and where electrical components would be problematic.

I have been poking around on the web, but I've only recently started, and I'm certainly no expert on pneumatics.

Thanks.

Andyhorning:

That's a lot of torque though. You're going to eat up a lot of energy just spinning the reduction gears if you use a vane type motor, and more with a turbine. If you need 250 Nm of torque at 200 rpm, that's getting to be bigger motor (or gearbox with a turbine) than I realized.

Have you considered using hydraulics. It is much more efficient for your application, and at 3000 psi, delivers much better torque and a lot more power in a smaller package. Hydraulic motors are very common for those reasons, not to mention the whole system is much more compact when you factor in the compressor and tank of a typical pneumatic system (screw compressors not included).

Also, is it possible your application allows locating the motor "inboard" to some extent and transmitting the power out to a final gear reduction by means of shafts and u-joints, or some other method? If the motors have to be light because they are near the end of some movable "arm" or assembly, this may have merit.

I haven't ruled out hydraulics at all. It's just that in my quest for some regenerative braking (the more the mass, the more I'll need) and the rather odd, cyclic damping needs of the system, I thought pneumatics made more sense in building a simple system.

Yes, it's lots of torque, and that's why I was thinking pistons, which, outside the complicated valving/timing needs, would work just fine.

I've got some cogitation to do...

You should try various manufacturers and pick there brains. Write down what you want to achive, with sketches, diagrams, explanations etc. Then call Parker, SMC, and Festo. You can find a distributor close to you, from their web sites. They may not have a one stop shopping but most of the sales personal are quite technical and can lead you down the right road.

Parker and Allenair have already been pretty helpful. I'll try the others. Thanks!