Flow Enhancement of Reciprocating Compressor

1. Magic.
2. Sorcery.
3. Witchcraft.
4. Booster compressor (but that would be disallowed as a revamp).

5. Faster motor.
6. Different drive belt ratio.

Run it faster, what else!

Forgot to say: And wait for the bang!

You might try this:

Thanks to Tornado for the inspiration.

Take two! This will least affect the rating!

Get rid of the leaks downstream of it in the first instance. The need to upgrade may go away.

zero

Connect the compressor output to a pneumatic motor that's driving an generator with an output greater than the compressor's rated input voltage, and then use that voltage to drive the compressor. _{you'll need to be quick when you switch the inputs}

Install a precooler/dryer.

Cooler air is denser and so the compressor will run for shorter periods for a given air volume., therefore higher efficiency.

The removal of water vapour at the inlet reduces the weight and density of the inlet air and so allows for more air to be compressed for a given volumetric capacity.

The result is higher efficiency, less wear and tear on the compressor, and more compressed air available.

Contact the manufacturer and find out what the capabilities of the compressor are. This should include, among other things: maximum hp for the compressor; max rotational speed; max pressure output; safe max pressure output; max. estimated cfm output; suggested drive pulley size for motor; whether a start/stop pressure switch or a pressure unloader or dual control can be installed; what voltage would be the best for the motor; and anything that comes to your or their mind. That way you can make safe increases that will not destroy the compressor or the motor. Manufacturers, their engineering depts. and service personnel should be the best to know and contact.

You don't provide much information, electric or fuel powered, # of pistons, pressurized or splash oiled, single/double/triple stage, etc. so it is hard to be specific and not just general.

The simplest increases are done by increasing the diameter of the drive motor pulley causing the compressor to increase in rotational speed. Caution- this most often has to be accompanied with an increase in hp of the motor. Manufacturers usually power their set-ups with the minimum hp that they have too, for cost and competitive reasons. Not increasing the motor hp will often cause premature wear or early complete failure of it.

I speak from personal experience. I was given a small newly rebuilt Quincy compressor (only the compressor) and the guy said it was good up to 3 hp. From the look of the compressor that sounded a little high. Called Quincy and talked to one of their tech persons and he said "NO!". He said 1-1/2 hp was the max for it and he recommended that I not exceed 1 hp if I wanted it to last a long time. I set the system up with a 1 hp motor with the pulley size he recommended, mounted it on a 30 gal tank and it can be depended upon to put out a quite, smooth, no oil using, 125 psi any time I use it. Much easier to use for small jobs than my 5 hp unit. It is pressure oiled with a cartridge filter so I want it to last!

Use caution and knowledgeable resources unless you want to take the chance of a pile of scrap iron ready for recycling at a scrap yard.

Good Luck, Old Salt

Adjust cut-out and cut-in pressure controls and run it higher pressure (but first check with mftr and do not exceed max design pressure). And/or run it at higher speed (if belt driven, change pulley ratios).

Watch it though, because the compressor will now run very hot and so will the motor.

Site compressor in cold air.

Hopefully both have temperature cut-outs to protect against damage by overheating.

Increase the suction pressure...

I'm surprised no one has asked what make and type the compressor is. It may just help, but as the questions from our old friend anonymous I doubt an answer will be forthcoming.

BTW I got involved in fitting a bigger motor and speeding a compressor up to try to squeeze that bit extra out of it, it didn't end well at all. It was funny though.

YES! YES! YES!

Tried to tell "mr anonymous" the same thing but many others spoke of "tricks". short cuts, mystery changes and whatever was the magic thing to squeeze another 1/10th of a cfm out of a compressor. What many don't realize is that once the maximum of the compressor, as you also stated, you can't get any more out without paying the price, the price being self destruction of the compressor!

What anyone contemplating this should do is "Contact the manufacturer and find out what the capabilities of the compressor are". Very simple! "You can't put 10 lbs of $hit in a 5 lbs bag without something breaking".

Very glad to see you limiting your reply to only the compressor. Fixing leaks, using colder air, refrigeration, and all those things are not boosting the output of the compressor, they are fixing and boosting the total output of the air system. OP was only about the compressor and what "anonymous" proposed is dangerous unless you make the changes within the capabilities of the compressor.

GA for you!

Good Luck, Old Salt

dear anon,

there have been lots of good replies already, so now for my 2-penn'orth (quaint old english expression)

- but it would really help to know if this is a "development project" where you are willing to risk breaking things (what fun!) or whether it must be risk-free (to the hardware, that is). It would also be good to know what sort of size beast we are talking about (in hp/kW and flow rate); other than the obvious upspeeding (already noted by others), "gas flowing" like car engine performance chaps do will increase the airflow by ensuring that the inlet pressure drop on the induction strokes is as small as possible, but, just as for an internal combustion engine, supercharging with some kind of (electrically) driven blower will give you best results. I would suggest a side-channel blower will give the right sort of flow rate and pressure ratio for some fun experiments and they are able to cope with a wide range of flow-rates so you don't have to worry too much about flow matching. The fact that you have another motor providing energy will assist your existing motor in its struggle not too burn out (but it will still have an increased load to cope with). Make sure that the outlet from the cylinder is obstruction free and that the outlet valve is also "gas flowed" to give low resistance to the compressed air. Good luck and don't blame me if it all goes wrong - don't forget that the man who never made a mistake never made anything!