Safe Max PSI for Compressor Tank

[efoda]

Hi there guys, this is my first post here. This is a really neat place and just learned about it a few weeks ago when buying things for my new shop. I searched for an answer to this question, but couldn't find anything and was hoping you might be able to help out.

I was wondering, if I have a compressor tank rated for 150 psi max (new), what would be a safe max pressure that I could put into it? Is there a rule of thumb percentage that is used?

Thanks a bunch.

 

[PAToyota]

Trick question? 150psi... That is figuring the safety factor into it already...

 

[efoda]

No, no trick question , but that might be right, that might be the useage rating, I'm really not sure.

It was certified by Manchester. Specs on the tank are MAWP 150PSI @ 650F, RT-NOMDMT-20F @ 150PSI. It's a 30 gallon tank.

I was reading the 150 as max values, but now that you mention it... not sure. So those numbers are working pressures? Anyone know where to find the key to those specs... sure there's got to be a standard somewhere

 

[PAToyota]

Yep - MAWP = Maximum Allowable Working Pressure.

 

[efoda]

Cool, thanks PAT!

 

[Roospike]

Normally, isnt the 135 PSI units 150 PSI tanks, and the 175 units 200 PSI tanks.

at least all the air compressors tanks i have seen over the years.

 

[Piper]

the only thing to make sure is that you don't run your system at the max pressure as most tools use around 90 psi. Blowing off your skin with anything higher than 40 psi can risk actually blowing air into your body. I've seen guys dust off cars with 120 psi which is just stupid. My devillbis compressor is rated at 150 psi, the switch cuts out at 125 psi and I have the max pressure set at 90 psi.

Piper

 

[kbs2244]

I cannot see any reason to have more than 120 PSI in the tank.
Even high pressure tools run at 90 PSI and you are for sure straining everything to get that last 30 PSI.
I don't do sand blasting or painting, so I got along fine for years on a home made rig that cut in at 60 PSI and out at 80 PSI.

 

[Curmudgeon]

I cannot see any reason to have more than 120 PSI in the tank.

The benefit of higher pressure is that you are able to store a larger VOLUME of air.

 

[Uncle Buck]

No, no trick question , but that might be right, that might be the useage rating, I'm really not sure.

It was certified by Manchester. Specs on the tank are MAWP 150PSI @ 650F, RT-NOMDMT-20F @ 150PSI. It's a 30 gallon tank.

I was reading the 150 as max values, but now that you mention it... not sure. So those numbers are working pressures? Anyone know where to find the key to those specs... sure there's got to be a standard somewhere

I do not know the answer to your question, but I can tell you where to get the answers. All pressure vessels are governed by ASME standards. I will do a little checking with our Chief Deputy Boiler Inspector, he will probably give me some more info to share.

 

[efoda]

The benefit of higher pressure is that you are able to store a larger VOLUME of air.

Exactly. I won't be using pressure at the tool greater than about 90. The extra pressure in the tank is so I can get longer tool useage.

Here's a great 4 part article all about compressors. There's a lot of misconceptions when it comes to pressure uesage vs. pressure storage and how that relates to cfm, etc. This site explains it better than I've read anywhere else:

http://mgaguru.com/mgtech/tools/ar101.htm

Enjoy

 

[drbill]

All the compressors I've ever seen have a blow off valve in case the limit switch fails and the compressor doesn't shut off.