Right now I have a couple of old hotdog style air compressors tied together in my garage. They are of the age that they are concerning me of possible tank rupture. I have no evidence they are going to have any issues besides the age. One is a 12 gallon compressor with no branding but is very old and has a slow turning single cylinder cast iron pump with a 1/2hp 110v motor. It cant put out more than a couple cfm at 90psi im sure. The other is an 8 gallon direct drive husky compressor. Its noisy but has been reliable. I run both compressors at the same time on a single 20 amp plug so clearly they arent that powerful. Combined they produce enough air for my needs have a 20 gallon combined capacity. I am looking to get rid of them and get a newer larger compressor. I like the looks of the mcgraw 29 gallon air compressor at harbor freight. Right now my store has one in the clearance section for $150 off of retail. My only concern is the tank is not ASME rated. The compressor has a 165psi cutoff and im sure for company liability reasons the tank is well equipped to handle much more. They probable did not want to pay for ASME rating. So how important is an ASME rated tank in a small residental 110v compressor?
How important is an ASME rated air compressor tank?
- Thread starter joegreen
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Years ago I would say no big deal of small diy compressors, most were made in the USA to a good standard of safety but today god only knows where some of the units come from and to what if any standards they were built to.
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Do you care if it blows up/explodes? On lots of small tanks, such as what you're talking about, it is common practice to put the ASME stamping directly on the shell itself, rather than have a separate nameplate; however, no stamping equals no ASME rating. I have seen such vessels (twice) being used in industrial settings; the maintenance men and inspectors (such as myself) spent almost 40 man hours going over every square inch of the 4' diameter X 8' long vessel and could find no stamping. Outcome: No stamping = not a code vessel. The maintenance superintendent ordered the vessel removed from service and scrapped. No ASME rating = Gods knows what you have. Can you spell liability? I would not be near it; and I HIGHLY doubt it is made in USA, in fact, I question everything about the vessel: The shell & head material, the welding processes and procedures used for assembly, the skill and credentials (if any) of the welders who assembled it, the filler metal, the manufacturers qualifications and certifications, (if any), the country of origin, the liability of the retailer, etc.
I am not on this forum to blow my own horn, but this question is right up my alley. I am a Certified Welding Inspector with 30 years + experience nearing retirement. This is the sort of stuff that makes newspaper stories. Not good ones.
I am not on this forum to blow my own horn, but this question is right up my alley. I am a Certified Welding Inspector with 30 years + experience nearing retirement. This is the sort of stuff that makes newspaper stories. Not good ones.
This is why I bought an Airkeg-it sits out by what I'm working on, crappy air compressor stays in the basement. At least if it explodes no one will be nearby to get injured!
I don't believe that it is legal to sell a pressure vessel (>15 psi) in the US without ASME. Sometimes they can be hard to find.
Thats interesting. I looked for a plaque welded to the tank as i thought that was all that showed there is an ASME rating. Usually it shows the max wp at whatever temperature along with dates and some other stuff. But if there is something else i should be looking for I would look.
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Murder, rape & robbery aren't legal either, but life and bad things happen. I have a hard enough time worrying about me, much less the rest of the world/country. I think it was Forest Gump's mom who said "Stupid is as stupid does."
Just talking a little common sense; it is very common on smaller vessels (think department stores & building supply stores) to have the ASME stamping directly on the tank (shell) itself, and sometimes it can be mostly filled with paint (hard to find). A bright flashlight held almost parallel to the surface can really make things "pop" out. I would also wager ANY manufacturer big enough to have a website is going to flat out state "ASME stamping" on their website.
So i took the fittings off of my compressor and looked inside the tank. I was very surprised to find it looks virtually new inside accept for one spot which is the lowest spot where water would normally sit. I tried scraping the spot with a long screwdriver and tried to get a close up of it with my inspection camera but i think you can get a better visual with just my phone camera.
I'm sure that the tank on the HF compressor meets the specs. HF wouldn't open them selves up to a lawsuit like that.
You may have been correct to worry because of age, but you inspected it and it looks almost mint. You also tested it to a pressure greater than it should see.
What’s the problem?
I have my pressure switch set to turn off at 125psi so i tested it to 130% which is basically 160psi. If i didnt have that little rusty area i would feel very comfortable with the tank. But my screwdriver was catching on some of the rusty area as it has some flakes of rust that came off and is somewhat pitted.
ASME doesn't do any certifications. You just have to take the manufacturer's word that it meets the appropriate ASME standard.
A lot of pressure tank failure concerns should be directed at where you live. Compressing warm, moist air in a high humidity climate is going to create far more water, (rust), than if the unit is used in a dry climate.
Back when I lived in the Midwest, I always drained my compressor at least once a week. I always got a lot of moisture out of it. Now living in a desert climate, I don't even bother.
My unit is still going strong after over 35 years of service. It usually kicks out at around 125 PSI of tank pressure.
Back when I lived in the Midwest, I always drained my compressor at least once a week. I always got a lot of moisture out of it. Now living in a desert climate, I don't even bother.
My unit is still going strong after over 35 years of service. It usually kicks out at around 125 PSI of tank pressure.
