Vessel design pressure query

[chemks2012]

Hello all,

One of our clients have a very old vessel for which original design documents are not available.
I want to size the suitable relief valve for that vessel but it can’t be possible unless I know the design pressure of the vessel.

Please let me know how to find out design pressure?

If I know the vessel design code [PD5500], do you think it would be possible to find out design pressure?

Thanks in advance
KS

 

[LittleInch]

Without calculations or a name plate, what your client has isn't a pressure vessel, it's a lump of scrap metal I'm afraid.

See

http://www.eng-tips.com/viewthread.cfm?qid=374741

and similar threads in the boiler and pressure vessel forum.

I don't know where you are or what jurisdiction you come under, but I would be very careful about doing anything with this vessel as it will then be your name on the document and if you're not qualified to do PV design then that is quite dangerous.

Without knowing the materials and the weld test results you might find the design pressure is too low for use.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[don1980]

As littleinch colorfully stated, you can't proceed without knowing more information. Relief design engineering can't be done without vessel design code and the MAWP (or design pressure). At least you know the design code, and with that you can have a vessel engineer calculate the MAWP. But first, the vessel engineer will need to know the metallurgy and thickness measurement for the vessel.

Tell the client that in order for you to perform this relief task they must first have a vessel engineer calculate the MAWP. Let the vessel engineer explain exactly what information he needs for this calculation. Once he's done, and supplies you with an MAWP, then you can proceed.

 

[chicopee]

If it is an ASME/NB pressure vessel, there may be a stamping on the shell plate, so carefully examine the surface close to man holes or hand holes. The stamping will bear the NB number which you can use to get a copy of the manufacturer data sheet from the NB. The stamping would also state manufacturer's name, year of manufacturing, MAWP and MAT. The relieving capacity on the other hand will based on the energy input in BTU/hr, Lbs/hr of steam or CFM from an air compressor to the tank as you have not identified the purpose of the tank.
Note just because it is an old vessel, that does not mean that the vessel has no remaining useful life.