Air Compressor Recommendations

[mariovillegas93]

I work for a university in a research lab and im having trouble finding a air compressor that will work for what i need. I have a 80 gal tank that can be filled to 100 psi of shop air. I need to tank the tank too 200 psi. I need to buy a compressor unit that can tank my pressure to that point. Hopefully find a solution that will tank less tha 15 min to reach that pressures. What solutions do you guys propose ? Ive calculated i need something that can provide around 13 cfm to get this done . Given the details ive found it hard to find something that will work. I was at first considering buying a compressor unit and gutting it and removing that actual air compressor and hooking it up that way.

What do you guys think ?

 

[GeoBruin]

Hello Mario and welcome.

Can you please clarify a couple things about your situation?

You said your 80 gallon tank can be filled to 100 PSI. But you then said you need to fill it to 200 psi. Is that because you have an existing means of filling it to 100 PSI but your compressor maxes out at 100 PSI?

Also, you said you calculated 13 cfm would be necessary to do the job, but the flow a compressor can deliver varies based on the pressure being demanded. In other words, a compressor might be able to deliver 20 cfm at 50 PSI, but only 15 cfm at 100 PSI, and much less at 200 PSI. So at what pressure did you calculate your compressor would need to be able to deliver 13 cfm?

I think what you are asking is doable, but depending on how much flow you need at what pressure, it might be the difference between a few hundred dollars and a few thousand.

 

[Tynee]

You'll want to check the Maximum Allowable Working Pressure on your existing tank before you upgrade the compressor. The existing compressor may be set to shut off at 100 psig to keep the pressure in the tank below MAWP.

 

[micromind]

If 175 PSI will work, a 5HP industrial model will be ok.

This is actual 5HP, it'll need 240 volts and 22-25 amps, not one of those cheap '5HP, runs on standard house current' ones.

 

[engineer2]

Will a Compressed Air Pressure Booster work?

 

[mariovillegas93]

Hello Mario and welcome.

Can you please clarify a couple things about your situation?

You said your 80 gallon tank can be filled to 100 PSI. But you then said you need to fill it to 200 psi. Is that because you have an existing means of filling it to 100 PSI but your compressor maxes out at 100 PSI?

Also, you said you calculated 13 cfm would be necessary to do the job, but the flow a compressor can deliver varies based on the pressure being demanded. In other words, a compressor might be able to deliver 20 cfm at 50 PSI, but only 15 cfm at 100 PSI, and much less at 200 PSI. So at what pressure did you calculate your compressor would need to be able to deliver 13 cfm?

I think what you are asking is doable, but depending on how much flow you need at what pressure, it might be the difference between a few hundred dollars and a few thousand.

Sorry, I shouldve clarified. In our lab we have a continuous 100psi air feed. The tank we are filling is rated for 200psi at 400F but we will mostly fill at room temp only. I do un derstand that cfm will change based on pressure increase. We we are trying to do is fill the tank 100 psi closing the shop air value and then using the compressor we are trying to use to get us to the 200 psi mark. We know that this 200 psi mark will not be maintained but we are trying to increase the run time of our experiments by having more pressure in our tank. What do you think we could use ?
I would like to get something like this , and hook it up but this one says its working psi is only 40

https://www.grainger.com/product/4B243?gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gad_source=4&gclid=Cj0KCQiApOyqBhDlARIsAGfnyMpYz43fyw8UU7csuD3FiVmKuwEizBmFa1qr3WW04m7W5FK_siW32bEaAkVxEALw_wcB&gclsrc=aw.ds

 

[mariovillegas93]

You'll want to check the Maximum Allowable Working Pressure on your existing tank before you upgrade the compressor. The existing compressor may be set to shut off at 100 psig to keep the pressure in the tank below MAWP.

So it isnt a tank with a compressor attached this tank is stand alone. The tank is rated for 200 psi at 400F so we think it will work fine at 200 psi at room temp

 

[mariovillegas93]

If 175 PSI will work, a 5HP industrial model will be ok.

This is actual 5HP, it'll need 240 volts and 22-25 amps, not one of those cheap '5HP, runs on standard house current' ones.

Have any links ? I would like to find something thats all together in one unit for easier installation

 

[micromind]

Have any links ? I would like to find something thats all together in one unit for easier installation

Just google '5 HP 2 stage air compressor'. If you have only single phase power, add that to the search as a lot of these units will be 3 phase.

The majority of 2 stage models will come from the factory set to turn on at 145 PSI and turn off at 175.

 

[GeoBruin]

Sorry, I shouldve clarified. In our lab we have a continuous 100psi air feed. The tank we are filling is rated for 200psi at 400F but we will mostly fill at room temp only. I do un derstand that cfm will change based on pressure increase. We we are trying to do is fill the tank 100 psi closing the shop air value and then using the compressor we are trying to use to get us to the 200 psi mark. We know that this 200 psi mark will not be maintained but we are trying to increase the run time of our experiments by having more pressure in our tank. What do you think we could use ?
I would like to get something like this , and hook it up but this one says its working psi is only 40

https://www.grainger.com/product/4B...3WW04m7W5FK_siW32bEaAkVxEALw_wcB&gclsrc=aw.ds

Thanks for the clarification. Unfortunately, most off the shelf units will come mounted on a tank, and for the output class you're looking at, those tanks are going to be in the 80 gallon range, which is pretty big.

In any case, 200 psi max pressure is kind of rare as most automotive and industrial applications operate at somewhat less than that. As others mentioned, 175 psi is more typical for an industrial compressor. If that's sufficient, there are lots of options available. If 200 psi is a minimum, that will limit your options pretty severely.

Also, as I mentioned, most manufacturers specify their output at a lower psi (90 is common, 100 is less common, higher than that is less common still) so it's going to be tricky to confirm they will make 10cfm at 200 psi.

Anyhow, here's a link to air compressors direct which is a great site that let's you filer by various specifications to find what you're looking for. Hopefully the link preserves the filtering which should be showing some 200 psi models.

Two-Stage Air Compressors

Two Stage Air Compressor superstore. Huge selection of 2 Stage Air Compressors. Buy Two Stage Compressor Direct and save.

www.aircompressorsdirect.com

 

[u3b3rg33k]

@mariovillegas93 have you reached out yet to your plant ops/facilities department? you absolutely should, both because they're probably a great resource and you will likely need their help/permission to install that kind of equipment per the local codes/facility regs. also you haven't mentioned what grade air you need for this, if it needs to be oil free, dewpoint, etc. there can be a lot more to this than just "slap a big box store compressor in a lab and go".

just as an example, at the appropriate speed, the QR-25 line is happy to do 200PSI all day.

Quincy QR-25 | Quincy Compressor

Get the facts on the Quincy QR-25 horsepower industrial piston compressor - the leading compressor in the industry. Click to learn about our top product!

www.quincycompressor.com

 

[Tynee]

So it isnt a tank with a compressor attached this tank is stand alone. The tank is rated for 200 psi at 400F so we think it will work fine at 200 psi at room temp

Makes sense. The only thing I'd be careful of there is using room temp. You'll want to consider derating the pressure rating of the tank based on discharge temp of the compressed air, not the ambient temp. A little googling should bring you to a pressure-temperature equation or table from ASME. This is worth checking with a professional on, since 200psi air inside a steel tank is a whole lot of stored energy.

 

[GeoBruin]

Makes sense. The only thing I'd be careful of there is using room temp. You'll want to consider derating the pressure rating of the tank based on discharge temp of the compressed air, not the ambient temp. A little googling should bring you to a pressure-temperature equation or table from ASME. This is worth checking with a professional on, since 200psi air inside a steel tank is a whole lot of stored energy.

He said the tank is rated to 200 PSI at 400 degrees fahrenheit.

 

[VolvoRyan]

Working for a university may limit your options pretty severely. Not only will they tell you where you can buy from, but there's a whole lot of money to spend on "project management".

I've been working in a major university anatomy lab for 20 years (Will spare you the power tool stories). Everything is a headache. We can buy from one vendor. Facilities charged us money to run electrical.... and "project management" cost us an extra $5K for the opportunity.

-Ryan

 

[Tynee]

He said the tank is rated to 200 PSI at 400 degrees fahrenheit.

Yeah, disregard. 250-ish is probably as hot as it will ever get at the discharge of the compressor.