Certify an old pressure vessel
Certify an old pressure vessel
(OP)
Hello all,
I have an old carbon steel horizontal tank that needs to be used as a pressure vessel (100 psi)
The tank has no stamp or plate. API 510 has provisions for getting a stamp for tanks with minimal information but I am having trouble finding out what needs to be done and what it would cost.
I have spoken to tank inspectors and their opinion is it would cost so much it is better to replace it because samples of the tank would have to be taken to determine the alloy, weld inspections etc.
The tank is large at 16000 gallons and NDT has shows that it is a minimum of 1 in thick. This is an OSHA PSM project if it makes a difference.
Can anyone give me advice on how to proceed?
Thanks,
Tom Jones
I have an old carbon steel horizontal tank that needs to be used as a pressure vessel (100 psi)
The tank has no stamp or plate. API 510 has provisions for getting a stamp for tanks with minimal information but I am having trouble finding out what needs to be done and what it would cost.
I have spoken to tank inspectors and their opinion is it would cost so much it is better to replace it because samples of the tank would have to be taken to determine the alloy, weld inspections etc.
The tank is large at 16000 gallons and NDT has shows that it is a minimum of 1 in thick. This is an OSHA PSM project if it makes a difference.
Can anyone give me advice on how to proceed?
Thanks,
Tom Jones





RE: Certify an old pressure vessel
RE: Certify an old pressure vessel
RE: Certify an old pressure vessel
needs to be usedsome cheapskate would like to use as a pressure vessel (100 psi)"Big difference. This has been discussed many times on this forum and the answer is always the same - no stamp / plate / paperwork = no pressure vessel = lump of scrap metal.
I don't know what it is you were thinking of storing in it, but that's a big volume at a decent pressure if e.g. the end fell off.
It kind of scares me a little that anyone is actually trying to do this.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Certify an old pressure vessel
I think replacement is the best option but the bosses (and yes they could be characterized as cheap) want to know what would be involved to code the tank and compare that to replacement costs.
RE: Certify an old pressure vessel
Either a new or perhaps used, but certified, pressure vessel may be best (and cheapest in the long run)
Cheapskate indeed .... all MBAs seem to put their staff through this useless "make-it-a-pressure-vessel" exercise
Ohh ... Has your boss yet told you that the project cost estimate does not include the cost of a replacement vessel ???
Azeo, please keep us informed about the final decision and the reasons for it.
You should be able to find prices for a used ~ 16000 gallon, carbon steel vessel on the internet ....
MJCronin
Sr. Process Engineer
RE: Certify an old pressure vessel
Anyway, if it's an inch thick, it wasn't built as a "tank", it was built for some kind of pressure service. But without any papers or knowing the construction details and past history, I would not be inclined to put it back into pressure service.
RE: Certify an old pressure vessel
Regards,
Mike
The problem with sloppy work is that the supply FAR EXCEEDS the demand
RE: Certify an old pressure vessel
However presumably something is changing if you're going from what the local inspectors signed off and now. So what are the changes ( pressure, contents, location, regulation??).
Let us know how it goes.
Remember - More details = better answers
Also: If you get a response it's polite to respond to it.
RE: Certify an old pressure vessel
You will need to determine the year of construction to determine the allowable stresses since the Safety Factor in ASME changed from 4 to 3.5 about 20 years ago.
You will need to check the PWHT requirements of the original Code of Construction to determine if it is exempt or not. Although it's probably not since it's less than 1.5". Note that the service may make PWHT a requirement as per UW-2. If PWHT is a requirement and you have no proof that it was done, you should do it again but be careful since the UTS drops with every PWHT performed.
You also have no proof that the welding was done by an ASME shop with an acceptable WPS, so this can never be fully compliant to the ASME Code and will never get a U-stamp or Manufacturer's Data Report.
This is a fair amount of work to not become fully compliant to the Code. I also suggest looking at replacement over backwards engineering it.
RE: Certify an old pressure vessel
RE: Certify an old pressure vessel
RE: Certify an old pressure vessel