How would I check a compressor tank?

[LoneGunman]

I'm in the market for a compressor and was looking at an Eaton 5hp, with shipping I'd be in the $1600 range. I can get an Eaton 10hp pump for $400 plus shipping (waiting on a shipping quote). I have a piece of **** 3hp 80 gallon now, so I'm thinking about getting the 10hp pump from Eaton and scrounging a 7.5hp or 10hp motor locally (eaton says a 7.5 will run it) ven if I came out to the same amount of money as the new compressor (It should be a good amount less) I am getting double the compressor.

My current compressor is 20 years old so I'm worried about the tank, it looks good but I havent looked on the inside. Is there anyplace that will recertify them or test them? What should I look for besides heavy rust on the inside?

 

[RickP330]

Check for an ASME stamp on the tank. There are guidlines for welded pressure vessels and it includes degration for rust over a period of time usually assuming worst case senarios. IMO 20 years is no big deal if it's been stored inside.
I worked at a plant in Long Island City and we had our tanks checked anually and these were big 500 gal? Rivited tanks (I don't even know how old they were...). They were still good to go.
HTH
Rick

 

[RickP330]

Oh, to answer your question, sorry, you would probably have it hydro tested.
Rick

 

[PAToyota]

Welding supply store should be able to tell you where you could take it for hydro-testing. They may even be able to do it for you.

Also, since you're going from a 3 to a 10 hp pump, I'd assume that the max. pressure of the 10 hp is more than the 3 hp. Make sure that the tank is rated to take that pressure.

 

[W-Cummins]

2 possiable problems I can see coming up
1st how big is the tank you have ( I hope at least 80 gal.) if not your going to be short cycling with that pump/motor combo as to starts per hr.
2nd 7.5 hp single phase motors are hard to come by "Scrounged up" and 10 hp are even harder to find as they are very rarely sold used...

You can probably start your tank inspection by removing the inspection plugs on it and looking inside. I'm assuming it's an ASME rated tank...

William....

 

[russlaferrera]

IMO, Buy the Eaton compressor complete. Sell all your scrounged stuff. The cost off set is NOT worth it.

 

[Elroy]

You can probably start your tank inspection by removing the inspection plugs on it and looking inside. I'm assuming it's an ASME rated tank...

Yep. If it is not a "code" tank, don't waste your time. Scrap it out for a new ASME code tank.

 

[LoneGunman]

IMO, Buy the Eaton compressor complete. Sell all your scrounged stuff. The cost off set is NOT worth it.

I think it's more than worth it, for the price of or most likely less than the Eaton 5hp I'm getting a 10hp. The 10hp pump would run me $600 shipped, the total shipped for the eaton 5hp is $1600, I can buy a 10hp Baldor right now for $800.

 

[nissan_crawler]

Don't forget a magnetic starter, they aren't cheap. You'll probably need a new pulley, too. Those aren't cheap either.

 

[LoneGunman]

Yep. If it is not a "code" tank, don't waste your time. Scrap it out for a new ASME code tank.

I checked the tank for the tag, the ASME tag reads max working pressure is 150 psi, so obviously I'd have to keep it below that.

 

[LoneGunman]

Don't forget a magnetic starter, they aren't cheap. You'll probably need a new pulley, too. Those aren't cheap either.

LOL how many would you like to purchase? I probably have 6 to 8 on a shelf in my garage and have access to another 20 or so in our shop at work. We do a good amount of industrial electric work at my job, I always save working starters that we replace.

 

[Blacktooth Grin]

I don't know if it will fit your application, but Grainger has a 10 hp farm duty motor for about $300 while supplies last.

http://www.grainger.com/Grainger/items/6K885

 

[W-Cummins]

I don't know if it will fit your application, but Grainger has a 10 hp farm duty motor for about $300 while supplies last.

http://www.grainger.com/Grainger/items/6K885

That is the deal of the month, maybe the deal of the year! If he is serious about building a 10hp compressor he should RUN and get one of these! DAM I have absolutely no use for one (don't have 240V power) and I'm thinking about buying one!

William....

 

[LoneGunman]

Damn, it's gone already, try to add it to basket and it lists as "no longer available". Thanks for the link though.

 

[Blacktooth Grin]

They also had 2 different 7.5 hp motors on their website for under $200, but they were out of stock when I called.

 

[malibu101]

I buy from Grainger alot. Call your local branch and ask them to look for you. VERY often there is 1 or 2 sitting in a branch somewhere in the country. They will bring it to your branch for you.
Never hurts to ask.