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Beware of Old Aircompressors

HIIFLY

Well Known Member
A few days ago I was going to fill up the air in my tires on my RV-8 , so I plugged in my 30 yr. old trusted Sears 2 hp 30 gal horizontal aircompressor .While I was 1 ft. from the end of this compressor filling up my portable air bottle , without any warning , it BLEW !!!!!! .At only 100 PSI of pressure in the 30 gal. compressor tank air gage . I am uninjured by the grace of GOD, and my RV-8 was not damaged . But to say it SCARED me is an under statment ! If you have an OLD COMPRESSOR BEWARE of What CAN HAPPEN ! :eek:
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A few days ago I was going to fill up the air in my tires on my RV-8 , so I plugged in my 30 yr. old trusted Sears 2 hp 30 gal horizontal aircompressor .While I was 1 ft. from the end of this compressor filling up my portable air bottle , without any warning , it BLEW !!!!!! .At only 100 PSI of pressure in the 30 gal. compressor tank air gage . I am uninjured by the grace of GOD, and my RV-8 was not damaged . But to say it scared me is an under statment ! If you have an OLD COMPRESSOR BEWARE of What CAN HAPPEN ! :eek:
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WOW! :eek:
 
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Just to be clear..

..it was your portable container that blew, not the compressor, right? Good thing you're okay.
 
Now you know why aircraft pressure vessels have a inspection cycle.
Really, 30 years old and you are surprised?
 
To be honest I have never really trusted air compressors. Every time the stupid thing cycles I get nervous. And mine is almost brand new! I'm sure it's an unreasonable fear, but... not that sure.
 
Wow, that seriously came apart. Glad you and yours are ok. I've watched buddies at the race track toss theirs into the back of their trucks and I always say....you know what 100psi does when that thing pops right? Now I have a picture I can show them!
 
Now there's an "interesting" sentiment.

--
Joe
(user of a 1957 Kellogg-American compressor)

OK, so that came out wrong. Obviously I didn't mean to imply that the plane being ok is more important than the OP's safety.
 
Aircompressor Blew Up

Thanks everyone for the well wishes . Just to make it clear , it was the "Aircompressor" that Blew up , not the portable air tank .
As far as being suppressed that my 30 yr. old compressor finally gave out , well it is like when an old Friend suddenly dies , you know it's possiable , but at what point in time ????? I guess in hind site I could have and should have disposed of it , I just didn't know when to . I am very sure I am not the only one to be hanging on to equipment that should be retired . I hope the word gets out so they can try and make that decision sooner than I did .
 
Thanks everyone for the well wishes . Just to make it clear , it was the "Aircompressor" that Blew up , not the portable air tank .

Glad you were unhurt.

So was the compressor and motor mounted to the exploded tank we see in the picture? It looks like this tank did not fail at the bottom where we would expect corrosion to be a factor, but rather from the top. Perhaps fatigue from compressor vibration at a compressor mounting point?
 
Glad you were unhurt.

So was the compressor and motor mounted to the exploded tank we see in the picture? It looks like this tank did not fail at the bottom where we would expect corrosion to be a factor, but rather from the top. Perhaps fatigue from compressor vibration at a compressor mounting point?

I think that is the bottom. You can see the drain **** on the left side of the pic. Funny how that bad word filter works.
 
Years ago, I had an old tank that went bad. It did not BLOW like yours. A rusted out spot blew out as a tiny pin hole and air bleed down.
 
how do we define 'OLD' ????

sounds like we need to borescope the compressor internals annually... or at 100hrs of use!?:rolleyes:

Now, with some of us having 50-year old cast iron compressors and steel tanks, or newbies with brand-new off-shore built tanks welded by heaven-knows-who....I don't think age or appearance, or even frequent bleeding is really a barometer of our expectations or real 'safety' level.

( heading to the garage now... to bleed my tiny compressor after filling up the winter tires yesterday!!!)
 
I wonder how many of us drain our tanks on a regular basis. I have known forever that I should, but rarely did. After having one tank rust through(while unpressurized) I finally put a HF auto-drain on each of my compressors. It is surprising how much water blows out after even short term use.
 
Leak before burst

Wow, pressure vessels are designed to be leak before burst. And to think that this one was 15 years newer than mine. Possible that it could be a manufacturing defect, maybe you should ask for a refund :D Can you post another picture of the rupture point and also of the motor side? I am wondering how close in design it is to mine. How far did it travel when it burst and how close were you when it let go? :eek::eek::eek:
 
Yeah, corrosion normally results in a leak first, rather than bursting. That is why I am wondering about the potential for fatigue.
 
Tank rust

How would you know?
I drain mine at least once a week. Depending on conditions, most of the time nothing but air comes out. Seems like the environment might be a factor in internal rust accumulation. Mine is about that age too!:D
 
I had a vertical one that rusted through and it just sorta went fsssssst one day. A small hole opened up in the bottom - a non event. Luck of the draw?
 
most of the time nothing but air comes out.

The best way to drain a compressor tank is to turn off the power, open the valve and let all the pressure out------and let it sit for awhile.

If you are just opening the drain valve while the tank is pressurized, the air will force through the standing water, and all you will see is air, while the water remains in the tank.

Been there, done that.
 
Near Miss - - -!!

Glad the poster is OK. This is one thing that product liability is good for . . . making manufacturers responsible.

I always use a tank that is ASME approved. Prevention, not a cure.

This is just scary! Will you notify the legal department of the "brand name" on the compressor/tank of this issue? Maybe send them a link to this post.

Although my 60 gal vertical is an ASME tank, the modern process is not to affix the ASME pressure vessel tag to the tank, and they HAVE gotten thinner. I shiver to think about what my house would look like if it bursts (in the basement) with 175 psi.
 
We pressurize very large tanks at work. A decade or so ago, an agitator in one of the tanks scored the inside of the tank creating a stress riser. The stress riser led to a failure.

There are few things more exciting than having the bottom blow off of a 10,000 gallon tank and launch the tank partially through the roof of your facility.
 
Another Tip

I installed a lever valve on my drain plug, to make it really easy to open and close. I also installed a long, clear hose for the fluid (and air) to drain through. 1) This setup takes all the loudness outside my shop and 2) the clear hose shows me if I have any rust. Since I drain my tank completely after every work session, I have no signs of rust at all.
 
OK, so that came out wrong. Obviously I didn't mean to imply that the plane being ok is more important than the OP's safety.

LOL! I knew what you meant. To the OP, you are one lucky dude. Time to buy a lotto ticket. Thanks for the heads up by the way. I wonder if there is a way to inspect the inside of our tanks?
 
HOrror Fright sells an automatic rank drain that opens briefly every time the tank cycles. It's pretty cheap. It's probably also pretty cheap :rolleyes:
 
Regarding tank drains... for you guys with vertical tanks, are your drains dead center in the bottom of the tank or off to one side? Mine - a 20 gallon Puma from Northern tool, which appears to be identical to several others I have seen - has the drain offset several inches from the center of the tank bottom, meaning I have to lean it over some to get all the water out. I've wondered if this is normal or not... it's a real pain in the rump to tip it over to the side to drain it, especially since it's in a pretty snug spot. I'd put an automatic drain on it, but it wouldn't drain the last half cup or so of water anyway.
 
Horror Fright Auto Drain Review

... I bought one of these before my current setup. It was @#$%. The metal bits failed within a day, leaving me with a need to patch up my "on/off" pressure line and look for a better option. Since my tank is only 30 gals and I vent all the bleed noise outside (see previous post), it's no big deal to drain it completely at the end of each work session.
 
Average lifespan or useful life of a compressor?

I have owned my Husky 30 gallon compressor from HD for about 5 years now. sadly I tend to leave the tank filled most of the time - which I never saw as a problem as long as I was actively working on the project and using the compressor. Probably need to rethink that a bit after reading several posts about failed compressors. I do drain it and change the oil seasonally.

The question that I have is what is supposed to be the 'average" useful life that one should expect to use compressors such as these before they should consider it having lived out its safe "useful life expectancy." I don't think my instructions mentioned anything about not using this compressor after a certain time period or number of cycles through the tank etc. So apparently we must simply guess as to when we think we should retire it.

So say you start seeing signs of some rust draining out of the bottom of the tank, which eventually clears up after it drains for a while. Is that a warning sign that you should replace the tank immediately? What if you drain it religously after each work session, and you see no signs of rust? Does that mean you can expect to keep using this compressor until the end of time? Will metal fatigue occur based on cycles of use (pressurized and depressurized) over a period of time? Will companies that sell pressurized vessels (welding suppliers, etc.) thoroughly inspect and/or recondition your compressor for you?

I am curious about how those that use compressors for commercial purposes handle this. Is there a strict maintenance or inspection schedule that is followed. Again, even if this is done, when do commercial operators decide that it has been used long enough and the time has finally come to replace it?
 
I have an 80 gal vertical compressor and the drain is in the lowest part of the tank. I purchased an automatic drain, which is basically just a timer and solenoid valve, and plumbed it to the drain. Works great. Lets a 2 second burst out every hour. I felt that was a little too much so I put a digital timer on the drain timer. Now it purges 2 seconds every hour for 4 hours, three times a week.

Tank is bone dry...
 
From the size of the tank and the handle that's visible, I have the very same compressor ... except mine is closer to 40 yrs old. I check it periodically for water and, to my surprise, never find any. It was always my assumption that a corroded tank would go "pfssssst" and leak away the pressure thru a pinhole. Looks like that assumption is not so good. :eek:
 
I'm guessing this is the make and model? This one has been passed around our airport and was recently given to me when someone saw me hand pumping up a tire. It actually works pretty good but I'm now thinking it could explode at any time. :eek:

Tick, tick, tick......

Sears.jpg
 
I have an 80 gal vertical compressor and the drain is in the lowest part of the tank. I purchased an automatic drain, which is basically just a timer and solenoid valve, and plumbed it to the drain. Works great. Lets a 2 second burst out every hour. I felt that was a little too much so I put a digital timer on the drain timer. Now it purges 2 seconds every hour for 4 hours, three times a week.

Tank is bone dry...

I've been thinking about this modification myself. Which valve & digital timer did you end up using?
 
What's in a name

You should be particularly concerned given your call sign of Boom ;)

I'm guessing this is the make and model? This one has been passed around our airport and was recently given to me when someone saw me hand pumping up a tire. It actually works pretty good but I'm now thinking it could explode at any time. :eek:

Tick, tick, tick......

Sears.jpg
 
The proper way to periodically test a vessel such as this, if one is concerned about the age or corrosion or whatever, is a bit cumbersome but safe and effective. I speak of course of a hydrostatic test, with water. Fill the tank with water, you probably want to disconnect and plug/cap the inlet from the compressor discharge line first, then apply pressure with a small low volume, high pressure pump, to a pressure at least 50 psi higher than the air pressure that you plan to have at any time. Beauty of this method is of course that as soon as the tank starts to fail, the pressure is all gone, with no danger of shrapnel, unlike with air which expands rapidly to many times its initial volume, causing the extensive ripping apart of the tank and danger to nearby personnel. The use of air dryers on the intake will also reduce the amount of condensation that can form in the tank and extend the life expectancy. A real pita, but no loss of limbs, eyes, etc. Not to say that I do this, but I think about it occasionally.
 
The proper way to periodically test a vessel such as this, if one is concerned about the age or corrosion or whatever, is a bit cumbersome but safe and effective. I speak of course of a hydrostatic test, with water. Fill the tank with water, you probably want to disconnect and plug/cap the inlet from the compressor discharge line first, then apply pressure with a small low volume, high pressure pump, to a pressure at least 50 psi higher than the air pressure that you plan to have at any time. Beauty of this method is of course that as soon as the tank starts to fail, the pressure is all gone, with no danger of shrapnel, unlike with air which expands rapidly to many times its initial volume, causing the extensive ripping apart of the tank and danger to nearby personnel. The use of air dryers on the intake will also reduce the amount of condensation that can form in the tank and extend the life expectancy. A real pita, but no loss of limbs, eyes, etc. Not to say that I do this, but I think about it occasionally.

How do you easily get 150 psi water at home?
 
After filling the tank with water, use a low volume, high pressure pump. Manual test pump is easiest, with a small piston and a long handle. Don't have to add much water.
 
Rocket ship

I saw a SCUBA tank rupture with about 2300 PSI in it. Went completly thru the roof of the dive shop to points unknown. I used to set and wait for my tank refill, after that I come back and pick it up.

BTW.. drain my vertical 30 Gal compressor every night. Old USAF habits die hard!
 
rust kills them

Drain the tank regularly, and even doing that will not guarantee that it will not do this. Usually it will start leaking first and at least give some warning. glad no one was injured..
 
Regarding tank drains... for you guys with vertical tanks, are your drains dead center in the bottom of the tank or off to one side?

This has been an interesting thread. My compressor tank is under pressure full time. Tank pressure us set to 175 psi and output is set to 100 psi and another drop down in the paint room.

It's a old vertical tank. While the drain is on the side, it has an interval weighted "snake" that drops to the bottom of the tank.

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How do you easily get 150 psi water at home?

You can put a 1/2 pipe standing out the top and use a hand pumped grease gun with a zerk fitting. The grease will float and be the first thing out the top when done. Easily controllable too.
 
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I have a vertical tank with a valve on the bottom. I replaced the valve with a brass elbow and a length of nylon tubing (rated to 250 psi) and another valve at the end of the tubing. That way, any condensation that forms in the tank drains into the tubing sitting under the tank. I can then use the valve on the end of the tubing to release any stored water. I drain it about once a week.

I had the Harbor Freight automatic drain for a while before I replaced it with the tubing and found that it tended to get stuck in the open position quite often.

PJ Seipel
RV-10 #40032
 
I wonder how many of us drain our tanks on a regular basis. I have known forever that I should, but rarely did. After having one tank rust through(while unpressurized) I finally put a HF auto-drain on each of my compressors. It is surprising how much water blows out after even short term use.

Drain mine every session. Lot's of red **** all over the rag I keep under the drain.
 
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