Proof of the BIG Bang Theory
 

http://i118.photobucket.com/albums/o...rg/aircomp.jpg

If you don't drain your air tank, there will be a BIG BANG.:eek:

I posted this a few years ago, but there are several new members here. I was in my basement working on the computor when I heard and felt an explosion. I went outside to see what happened, and found my neighbor standing in his driveway looking like he was in a state of shock. He was using his air compressor to blow the grass off his lawn mower when the air tank blew up.

He had a garage full of Harleys and expensive cars and only about 6 feet by 6 feet of open floor space. He had his compressor mounted up on a shelf about 6 feet off the floor. When it blew it knocked the outside lights off the garage wall, blew the shelf away and the compressor landed on the only open space left. He was lucky, but the cars and Harleys were all splattered with rusty water and oil slime.

He gave me what was left of the compressor, and I could see the rusty water line about half way up the tank. I also saw a sheet metal screw sticking inside the tank. Apparently a couple years earlier the tank had sprung a leak through a rust hole so he plugged that hole with a sheet metal screw and kept using the compressor and kept on NEVER draining the water.

Re: Proof of the BIG Bang Theory
 

Never mind the harleys. He is lucky he was outside when it blew up. I learned air compressor maintenance when I was in the US Air Force. I regularly drain my tank, and change the oil in the compressor. My setup has a really heavy large tank, not a thin one like your photo. Even so, it is in the back room, away from people.

Re: Proof of the BIG Bang Theory
 

I worked at a store where compressed air was used. SOP at the end of each day was to open the petcock at the bottom and drain air/H2O out the bottom and leave them open until next day.

Re: Proof of the BIG Bang Theory
 

Re: Proof of the BIG Bang Theory
 

Tom - Thanks for the heads-up information, I actually purchased my 1st air compresser yesterday and appreciate your advice.

Re: Proof of the BIG Bang Theory
 

My tank and pump are (were) 1946 vintage.

About a year ago I was in the garage and heard a light hissing sound from the bottom of the tank. It was not the drain.

I let the air out and tore the pump and motor off and scrapped the tank. Oh ya, I put a larger hole in the tank just to be sure it was not used. My city picked it up as they get the extra money doing metal scrap runs.

Lucky for me the modern compressors blow up easy. Bought an almost new tank with blown compressor cheap. Put my nice old last forever 5 HP compressor on top and it has been fine since.

It is not hard to test your tank. I found several sites explaining that you test the tank by filling with water and then use a grease gun to pressurize the tank.

You can also find some interesting stories of blown tanks. In one case the tank blew the side of the garage out and the roof came down on top. Needless to say they deserve your respect.

Re: Proof of the BIG Bang Theory
 

I installed and Auto-purge on the bottom of my upright Air tank and it works great. However, I still open the cock ever so often to make sure.

Re: Proof of the BIG Bang Theory
 

He almost qualified to win the Darwin Award :)

Re: Proof of the BIG Bang Theory
 

Looks like something that should be on Mythbusters. But thanks for the reminder to check the drain.

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I was surprised at how much water accumulates in the tank on just one day's operation... worse in humid climates !

Re: Proof of the BIG Bang Theory
 

You know one thing I never figured out.

Before I traded my 92 chevy pickup in I had a $700 train horn on it (don't ask.. I've grown up since then). Was rated 152dB at 5 feet.

I used a oiless Thomas compressor with a PTFE coated piston and a 3 gallon tank. Every time I went to drain water from the tank it was ALWAYS bone dry.

The horn pulled air from around 4 inches from the bottom of the tank as it was a cylinder. The drain was on the bottom of the tank. Only thing I ever assumed was the water was being sucked out of the tank by the horn some how.


I ran it at 145psi but doubt that matters.

Re: Proof of the BIG Bang Theory
 

You don't hear many of them anymore, where as before you heard them all the time...

I was standing outside a concert venue having a smoke when this guy blew his train horn at the crowd. He was stupid enough to come back around a second time and when he did the concert goers threw beer bottles and rocks at his car. That one toot of the horn probably cost him a few bucks for replacement glass and paint touch-up. HAHA.

Re: Proof of the BIG Bang Theory
 

Yea, I was never dumb enough to do it just to annoy people.

I did it more when people in central NJ scared me half to death with their driving.


Over time I realized it caused more problems then it fixed and decided it was immature and time to grow up.

It was great when you had someone honk at you for taking too long at a stop sign or stop light though :D. You could watch them jump and then get a confused look when you replied.

Re: Proof of the BIG Bang Theory
 

Here in the Houston TX area it is a lot.....When the humidly is near 100% most of the time.

Re: Proof of the BIG Bang Theory
 

That's a pretty tinny-looking air tank!

If anyone hasn't seen the Mythbusters Exploding Water Heater episode, go check it out. It's amazing!

Doug

Re: Proof of the BIG Bang Theory
 

My friend was using his portable air compressor about 15 years ago when he said it exploded. He said the bottom split open and it blew about 20 feet straight up and landed in about the same spot it launched from. Luckily he was some feet away from that spot.

Re: Proof of the BIG Bang Theory
 

I have a 42 year old craftsman 1 hp compressor. It shuts off at 80 psi and has a small pinhole in the bottom of the tank. I want to replace the tank with a portable compressed air tank from harbor freight. The harbor frt tank only has 1 pipe fitting on it. I want to add other fittings to the tank for inlet/outlet and drain but I only have the capability to braze them on this tank. My question is would the brazing be strong enough? Like I said the compressor shuts off at 80 psi. I realize that this may be a jury rigged way of fixing it...comments welcome. Franco in PA

Re: Proof of the BIG Bang Theory
 

I wouldnt do it, I dont think braze would be strong enough. Whatever you do make sure you incorporate a pressure relief(one of those spring loaded valves with the little pull ring) in case the 80 psi shut off doesnt shut off!

Re: Proof of the BIG Bang Theory
 

put a "T" in the hole do not try to change the tank.

Re: Proof of the BIG Bang Theory
 

I keep my air blead on the bottom just a tinny bit open at all times so it will slowley leek air and in turn blow any watter out the bottom. Iv had this 5 hp compressor for 6 years and i think its about to die when it dose I have afew extra 400 galloen tank 3 phase compressors at work ( i own an architectural mill) and im going to build eather a shed off the grage or when i build a new gradge this year have it put in the atick before the roof goes on. Ill hook up a dryer to it.

Re: Proof of the BIG Bang Theory
 

Thanks for all the advice. I'm going to scrap (cut a hole in) the old compressor tank and I'm just going to buy an inexpensive air compressor to take it's place. Franco

Re: Proof of the BIG Bang Theory
 

A pressure vessel like we are discussing should be welded to add fittings. However it is only appropriate for a 'code' welder to do any welding on such a vessel. Be very careful with these tanks or vessels. All official testing is always done with liquid (water), as any crack or leak will quickly lower the contained pressure. Obviously that is not the case when they are gas (air) filled.

Re: Proof of the BIG Bang Theory
 

I agree with the posters advocating an experienced certified welder do any mods to preesure vessels. However I wanted to add that in the 60's I had a Formula Ford Racing car whose entire tubular space frame chassis was nickle-bronze brazed together. It was hit broadside by at least two cars going 100+ MPH and the actual tube members failed,not one brazed joint failed. The car was repaired ,with braze, and survived another crash (driver error) with no failure of a brazed joint. Properly done a braze joint seems to be adequate . My experience. I would guess I would rather have TIG now.

Re: Proof of the BIG Bang Theory
 

Recently there have been several new posters on Fordbarn, so I just mention this as a reminder that air compressors need to be drained on a regular basis. This means drain the water off the bottom, not drain all the air from the tank.

Re: Proof of the BIG Bang Theory
 

Not my compressor, but 30 years ago I was airing up an old tire/tube that came on a 21" rim. Checked at 10 psi, 20 psi looked ok so I figured I would see if it would hold 35. I was about 32, when it blew. My neighbor and fathe came running from different directions. Shook the garage door and blew out a window. My hearing was messed up for about a day and the garage was filled with a black dust. I was dumbfounded it was such an explosion.

Re: Proof of the BIG Bang Theory
 

At work they just got a "new" air compresser, it looks new, the paint is perfect, but the date on the tank is 1988, the paint is so perfect that there wasn't even a chip on the paint of the drain plug for the pump oil sump---same for the drain petcock at the bottom of the tank, and when forced open nothing came out, there is also an automatic drain ---both drain pipes were so clogged with rust that I had to drill them out.

I modify the drains ---my idea is if they are made easy to use the tank will be drained, I get rid of the old style winged petcock that is normally used, I extend the drain with a street elbow,a pipe long enough that a modern small ball valve with the easy to use lever is in a position that there is no crawling around and fighting to drain it----just lean over and turn the valve

Re: Proof of the BIG Bang Theory
 

I would assume you could even use some type L copper pipe and plumb it from the bottom of the tank using a brass connector and run it up to a nice reach level, install valve and then run it back down to a bucket. Should still drain any fluid and would be really easy to open and close, no bending over!

I guess I just showed how lazy I am. :rolleyes:



Thought I'd add this to the thread. Though its a water heater from the 1920s and not an air tank I feel they share the same dangerous in many ways.

https://sphotos-b.xx.fbcdn.net/hphot...31511703_n.jpg

Re: Proof of the BIG Bang Theory
 

I work part time in a hardware store, where we purchased a used compressor for small engine service. The age of the compressor is unknown, but looked to be in good shape. I drained the tank after every use, but who knows what the previous owner did with it.

One day, I had it running and under pressure, when I heard leaking air. Yup, you guessed it, the tank was leaking. To say the least, it was shut down, and the pressure was bled off. The tank was disconnected from the compressor.

Not having a spare tank lying around, and being on a tight budget, I improvised. Used an 8' length of 2" schedule 40 pipe and a few fittings for a receiver. Just moved the pressure switch, and relief valve over to the pipe and went from there. It does not have a lot of air capacity, but between the pipe and 50' of 3/8" air hose there is enough capacity there for our needs. There is enough air available to run an air ratchet and a small 40:1 chassis pump.

Chris

Re: Proof of the BIG Bang Theory
 

Here is a water heater explosion film from years ago. Watts brought the original film to one of our plumbing contractor meetings years ago. Quite impressive! Also guys why don't you go see if you have a temperature and pressure relief valve on your water heater and scrap those old air compressors that are questionable. Hope the link works for you.

https://www.youtube.com/watch?v=5pVQryuKMj8

Re: Proof of the BIG Bang Theory
 

Nice video!

Re: Proof of the BIG Bang Theory
 

I would not go near any tank or vessel with either water, steam, air or what ever without a working SAFETY blow off. JMO

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I have two IR auto releases in my compressed air system, one at the bottom of the tank and the other about 50 feet away at the end of the long very slightly sloped pipe run that feeds all my service drops.


the tank drop has liquid all the time in the tray below. the other one not at all.

Re: Proof of the BIG Bang Theory
 

I had a Mexican taqueria owner, who believed in jerry rigging everything. Unfortunately he had no mechanical insight whatsoever. His water heater started popping off the relief valve, so he screwed in a 3/4" plug. Shortly thereafter, it blew. Went thru the attic, the roof, across kfc, across a 5 lane road, and landing in the middle of pizza huts parking lot. No one was injured. He moved up the street to a new location, because his building was toast. A year later, I went in to work on a fryer , and the fool had jumpered the hi temp limit. Oil will burst into flame at around 450/500 degrees.

Re: Proof of the BIG Bang Theory
 

The tank does not look like it blew out because of rust. It looks like the tank could not hold the pressure that it was subjected to and yes the rust could have contributed to the explosion. I would like to see the blow off or any safety features on the unit. JMHO

Re: Proof of the BIG Bang Theory
 

It was done in by the rust. The metal is very thin and jagged where it spit apart. The water that was in the tank sure made a big mess on his Cadillac and Harleys.