80 gallon Air Compressor - what do you think?

[msgross]

I decided that I need a "real" compressor in order to get more body work done on my truck. I really don't want to spend $700+ on a new one and need some decent CFM's for my tools. Plus it's nice to have one that will run anything in your arsenal.

I found this beast and it looks like it will do the trick. No idea how many CFM's but I can tell you that a die grinder at 80psi hardly dropped the pressure gauge once the motor kicked on. Neither did a blow hose.. It must weight 500lbs and be 50+ years old but it seems to work well and the guy has it fairly air tight too...


$200 seems like a good deal for an 80 gallon tank... thoughts?

[N2TRUX]

Old and ugly, but 200.00 is a deal. That thing was built with real steel and cast iron.

[rwolf9653]

My thoughts............
80 gallons should be enough
price is right
older is almost always better
made in PA! (no rational to that, but I like it)

Have you tried looking up parts for it?? I went with an Ingersol Rand only because they have been around for a long time so chances are so will their parts in 50 years.

[msgross]

I just looked up a few websites and Keystone compressors has been out of business for awhile! But this beast has run for a half a century so it should give me a few more years huh?

Old and ugly is right, like something out of Dr. Frankenstein's lab!

1. It runs
2. It blows a LOTTT of air
3. $200

[El Jay]

I would only have 1 concern, and that would be internal corrosion in the tank, especially since the unit is 50 yrs. old.

If the pump/motor went away, they can be replaced, even if you have to fab new brackets for it/them. It looks like a decent platform on the top of the tank for installing replacement parts/fabbing new brackets.
Just don't weld new stuff to the tank unless you are certified on pressure vessels.

Happen to know any NDT folks?

[msgross]

NDT like testing?

the tank seems to be so thick I don't know if the corrosion would hurt it much... He does have a 60 gallon for $300 and it's newer...

I was also watching some government auctions in my area that have 15cfm setups with gas engines... prices are around $200 right now..

[Bus Ted Knuckle]

Mike, don't worry about gallon size, 60 or 80 will do you fine.

DO be concerned with CFM ratings. If you don't have the CFM's you need, tank size won't mean a hill of beans.

[100%Chevy]

Looks like a 2 stage pump!
What's the H.P.?Hopefully 5 or more.
What's the r.p.m.?1850 is better than 3600.
Looks like a replacement motor.
I'd beware of the tank---Put it behind a barrier or something for missile protection!
I think it's a very good price,compared to what I paid for a new I/R unit a couple years ago!
Mike.

[jeffspower]

If it isn't pumping oil, and the tank isn't ready to blow... it was a good deal. Since it has a big plug towards the bottom, you could look in it to see how rusty it is. If in question, you could have a sonic thickness check done. If you know anyone with concrete trucks, they could do it. Some of them have a tester that they use on mixer drums... 5 minute deal. 5 minutes that could save a life- tank explosions can be UGLY.

[El Jay]

Originally Posted by msgross

NDT like testing?

the tank seems to be so thick I don't know if the corrosion would hurt it much... He does have a 60 gallon for $300 and it's newer...

I was also watching some government auctions in my area that have 15cfm setups with gas engines... prices are around $200 right now..

Yeah, Mike,, NonDestructive Testing

If you have any refineries, chemical plants, etc. in your area; you probably have several NDT cos.
Maybe you could find somebody to "moonlight" the job.

I'm not trying to "harp", or sound superior, or "holier than thou" to anybody.
I just happen to have a personal aversion to shrapnel.
Nobody really knows the history of the tank. Who among us drains the water out of their air tank everyday? I know I should, but I don't. I've been know to leave the compressor running for several days, just so I don't have to "waste time" recharging the air system in the morning. I've been going to install that "spitter valve" for the last 20 yrs., just never seem to get around to it.

In my personal experiences (none with air tanks, to be honest) with pressure vessel failures, they seem to be of 2 kinds; "Hey we have a 'weeper' on WXYZ vessel", or the failures are catastrophic. There just didn't seem to be much middle ground in that area.

I apologize to everyone for the very long post, but in my mind, personal safety is #1.

I'm going to ride off into the sunset on my high horse now.

LJ

[hgs_notes]

I'm a boiler and pressure vessel inspector by trade. I look at 1000's of air compressors. I've never seen that particular brand, but if you find the metal nameplate on the tank it will show the year built and pressure rating, among other things. Sometimes they even have the thickness for the heads and shell stamped on them (that's a current requirement). Anyway, in my experience these things rarely rust out from the inside. There is too much oil carryover to the tank. On the other hand, if it sat for a few years with water in it, it may have pitted some. Easy enough to find out, just open one of the plugs in the side or bottom and take a look. The other trouble areas on these are where the feet are welded to the tank (sometimes they crack) and the fittings themselves will occasionally crack. After more than 15 years on the job, including 3 working at an air compressor manufacturer, I've only seen maybe 10-15 tanks that failed.

Your biggest concern with this unit would be finding replacement pump parts, but that can be solved by replacing the pump.

[El Jay]

Originally Posted by hgs_notes

I'm a boiler and pressure vessel inspector by trade. I look at 1000's of air compressors. I've never seen that particular brand, but if you find the metal nameplate on the tank it will show the year built and pressure rating, among other things. Sometimes they even have the thickness for the heads and shell stamped on them (that's a current requirement). Anyway, in my experience these things rarely rust out from the inside. There is too much oil carryover to the tank. On the other hand, if it sat for a few years with water in it, it may have pitted some. Easy enough to find out, just open one of the plugs in the side or bottom and take a look. The other trouble areas on these are where the feet are welded to the tank (sometimes they crack) and the fittings themselves will occasionally crack. After more than 15 years on the job, including 3 working at an air compressor manufacturer, I've only seen maybe 10-15 tanks that failed.

Your biggest concern with this unit would be finding replacement pump parts, but that can be solved by replacing the pump.

I personally thank you for your input, Sir.
Like I said, I never saw a failure in an air tank.

I did spend over 2//3 of my life working in a refinery & in that environment; when things decided to go south, they took the express.

It's always refreshing to see/read about somebody else's experiences & learn from them.

LJ

[msgross]

great input from everyone.. if we had rep points i'd give them!

I doubt that replacement parts are around for this old pump either, but who's to say it will need rebuilt in the near future...? it's a slower RPM pump..It has a badge on it that makes me think it was a Penn DOT (transportation) garage unit. This is a VERY thick tank that's only set at 135psi right now... I'll have the guy pull a side cap off and peak in with a flashlight before I bring it home... the oil cooling fins on top are crazy looking... The compressor was cool to the touch while running and pumped this up in 15-20 minutes.. The cylinders look like something from a car too!

[Longhorn Man]

I've seen 2 tanks fail, and they just hiss ans split, never violently.

[hgs_notes]

For safety sake, replace the relief valve that is on the tank. If it's a thick tank it was probably rated at 200 psi. Whatever the nameplate rating is for MAWP is the highest you put on for relief valve setting. Some of the older tanks have odd MAWP ratings, like 137 psi. If it's running at 135 and that's adequate for you, then a 150 or 165 relief would be good. I've seen some 2 stage pumps that are running at 175 with 200 psi reliefs that are fine. The added pressure means there is more air volume in the tank and the compressor will recycle less often, but for a longer run time. If the tools are not rated for that pressure, just use an in-line regulator.

[msgross]

good call on the pressure relief, it does have one on it but who knows the proper function... It has an old school type pressure switch that turns the motor on and off but should that fail I could see a fitting getting shot out like a bullet..yikes..

[bpmcgee]

With a two stage compressor like that, I wonder are you going to get enough air flow? Many of the big tank systems have a 3 stage compressor.

Of course, for $200 you could afford to replace it with a 3 stage compressor and still be less than the cost of new.

B

[MacAttack]

Originally Posted by Longhorn Man

I've seen 2 tanks fail, and they just hiss and split, never violently.

Same - same. A pressure relief valve will do just fine and that tank probably has another 100 years of service life. Drama factor: Extremely Low.

Mac.

[msgross]

Originally Posted by bpmcgee

With a two stage compressor like that, I wonder are you going to get enough air flow? Many of the big tank systems have a 3 stage compressor.

Of course, for $200 you could afford to replace it with a 3 stage compressor and still be less than the cost of new.

B

I took my die grinder and set the regulator at 80 lbs, it would draw the tank down to 100psi then it kicked on and barely went below that... that was a few minutes straight without stopping which isn't how most guys use the tool... It might be two cylinders but they are larger than a modern compressor... I bet they have 3-4" wide cylinder heads...

[basemodel67]

I'd use it just 'cuz it looks like an old BMW motorcycle engine. Way cooler than any new compressor! And the slight possibility of tank explosion makes every time in the garage an adventure.

[LooseCannon]

Looks like a good score.

[jeffspower]

Originally Posted by MacAttack

Same - same. A pressure relief valve will do just fine and that tank probably has another 100 years of service life. Drama factor: Extremely Low.

Mac.

Originally Posted by Longhorn Man

I've seen 2 tanks fail, and they just hiss ans split, never violently.

Some friends were sitting on the porch years ago and heard a big boom out in the barn. They had just been in the loft puttin' up hay. The compressor that was in the ground area shop was found in the loft!

Not sayin it will happen to this one, or that it does often, but it does happen.

[MacAttack]

Our shop has an I/R screw compressor with a relief valve that keeps the huge tank safe - anything could happen - and probably has, at some time - in some part of the world. But unless the pressures are extreme and uncontrolled - it's remote.

[thump16]

nice find. I recently picked up a 60 gallon 8 hp compressor for free.