Old air compressor?

[topgun3690]

Was on another forum and a poster was talking about getting a new air compressor for his shop.....he posted a youtube video of an old compressor blowing up and seriously injuring a man in his garage, caught on the man's home surveillance video camera. The thing literally exploded like a bomb, sending shrapnel into him and blew out windows and damaged doors, etc. So I searched the web and found other videos and accounts of other compressors blowing up. Always wondered how long my old compressor would last....going on 30 years now....always drain the water after every use, and change the oil every year, probably why it has lasted this long. The videos and accounts I saw didn't say exactly why they exploded, could have been internal rust or a pressure relief valve malfunction, or a combination of both.....in any event, I think it is time to get a NEW air compressor. Anybody on here ever have one "blow"?

 

[racerone]

I use my compressor on occasion.-----The drain valve is left OPEN just a wee , wee bit.----Automatically drains condensation when it is used.------If you have an old compressor then a HYDROSTATIC test is a good idea.------There must be guide at what pressure to test it at.

 

[jakedaawg]

Mines more than 50 year old Saylor beal. Maintained twice a year. Used daily. Never turned it off except twice a year to do the oil change and drain. Being a tenhp 120 gallon job at 200 psi, if it goes I won't even know.

 

[racerone]

Agreed------If you stood next to it when it ruptured it would be LOUD and perhaps very painful for a few seconds.----U-tube has videos how you can test your tank at home.------If 50 years old then I would replace it.

 

[jakedaawg]

Agreed------If you stood next to it when it ruptured it would be LOUD and perhaps very painful for a few seconds.----U-tube has videos how you can test your tank at home.------If 50 years old then I would replace it.

It gets certified whenever the service company says so. I think they test it every 3nyears, maybe 5? Not gonna shell out 7 grand till they say. A lot of these ac threads are oveblown...excuse the pun. So much more likely to get a pin hole leak than a catastrophic failure. You can find any fear on the net.

 

[topgun3690]

jakedaawg....sounds like you are on top of it with your tank maintenance.....having it pressure tested every few years and inspected....yours sounds like a heavy duty commercial rig, probably has thicker steel tank than the average retail bought unit. Most of the ones in the videos looked like what I have, just your average compressor you can buy at the hardware store. And every time when I drained the tank, when my body is directly over it and reaching down under the tank to open the drain valve, I thought about it letting loose......

 

[topgun3690]

"If you stood next to it when it ruptured it would be LOUD and perhaps very painful for a few seconds.---" Agreed....

 

[Krazeehorse]

Check those pop off valves regularly. You should do this on your water heaters too.

 

[matt167]

If you have an industrial type compressor, it's probably fine at any age. The tank will be ASME certified.. Many homeowner compressors do not have a certification and are not really designed for long term use.. Seen the aftermath of a few.. The one in question was a homeowner unit..

My compressor is an 80 gal unit I got for free from work. I had to put a new pump on it and get the motor rebuilt ( $300ish into it ). tank made in 1988 but it does not bother me. The tank is heavier than the tin can tanks you get without spending over $1k

 

[bruceb58]

I have an auto drain on my compressor. You hear stories of people who never drain their compressor tanks. They are the ones that have problems with their tanks.

 

[topgun3690]

"Many homeowner compressors do not have a certification and are not really designed for long term use.. " I think that pretty much sums it up right there....my 30 year old "homeowner unit" has served me well but I reckon it's useful life is over.

 

[bigdee]

So much more likely to get a pin hole leak than a catastrophic failure. You can find any fear on the net.

I would think a combination of problems could cause a catastrophic failure like a stuck pressure switch and absence of a pop-off valve. Rusty tanks usual develops pinholes,as said.

 

[bruceb58]

My friend, who is an ME, does product liability investigations. He represents the manufacturers. One of his cases was doing expert testimony on a Sears air compressor. The tank that exploded was due to rust damage from the owner who never drained his tank. The tank will explode long before a pinhole would develop.

 

[topgun3690]

"My friend, who is an ME, does product LIABILITY investigations." Another reason to properly "decommission" my old compressor....render it unusable to end it's potential for devastating litigation.....and get a new one.

 

[bigdee]

"My friend, who is an ME, does product LIABILITY investigations." Another reason to properly "decommission" my old compressor....render it unusable to end it's potential for devastating litigation.....and get a new one.

I agree. newer tanks come with an expiration date. I have seen many small air compressor tanks in the construction industry develop pinhole leaks that are plugged with sheet metal screws to complete a job. My theory is beside rust being a factor is metal fatigue from repeated cycles. Although it is very slight the walls of a cheap tank flex. This is also a common problem on water heaters that become noticeable after codes required a check valve on the water main. The tank would build pressure and flex with each heat cycle until the metal fatigued. That problem was resolved by another code that requires a expansion bladder/tank in the system to dampen the pressure fluctuations.

 

[topgun3690]

I agree. newer tanks come with an expiration date. I have seen many small air compressor tanks in the construction industry develop pinhole leaks that are plugged with sheet metal screws to complete a job. My theory is beside rust being a factor is metal fatigue from repeated cycles. Although it is very slight the walls of a cheap tank flex. This is also a common problem on water heaters that become noticeable after codes required a check valve on the water main. The tank would build pressure and flex with each heat cycle until the metal fatigued. That problem was resolved by another code that requires a expansion bladder/tank in the system to dampen the pressure fluctuations.

You are right bigdee....the combination of age, corrosion, and metal fatigue will take it's toll on a pressure cylinder over time.....the aviation industry is acutely aware of the problem, having many "time-life" components that at a certain amount of hours in service, the part is replaced and the old part is destroyed, no matter how good the part appears to be.....