Pressure Vessel Standards
Pressure Vessel Standards
(OP)
I am looking for the ASTM (or other) standard for pressure vessel design and safety considerations. Specifically, I want to know if there is a recommended factor of safety for pressure vessels -- I remember it to be 3, but I can't recall from where. -- and proof testing methods, including frequency. In other words, before I put the pressure vessel in use, to what pressure must I test it for leaks? Once the vessel is in use, how often do I have to inspect it: 90 days, 180 days, yearly?
I searched the ASTM web sight by title ("pressure vessels") and came up with 112 possible standards. I could really use some help in narrowing my search.
The vessel will be made of stainless steel, hold a volume of 19 in^3, and be used in a hydrostatic test fixture as an accumulator that can see 40 ksi.
Thanks in advance,
--Scott
I searched the ASTM web sight by title ("pressure vessels") and came up with 112 possible standards. I could really use some help in narrowing my search.
The vessel will be made of stainless steel, hold a volume of 19 in^3, and be used in a hydrostatic test fixture as an accumulator that can see 40 ksi.
Thanks in advance,
--Scott





RE: Pressure Vessel Standards
This code requires one to consider allowable stress to be 25 % of the ultimate tensile stress, thus giving safety factor of 4.
Equipments designed as per ASME Section VIII are hydraulically or pneumatically tested to 1.5 tims the design presure for at least half an hour.
RE: Pressure Vessel Standards
However your vessel is so small that will likely be outside the scope of any pressure vessel standard, so that you can design and test it to whatever criteria you want.
Keep also in mind that the first usage of ASME VIII (as any other pressure vessel standard) is quite difficult for a non experienced user: I strongly suggest you to consult first one of the available books on pressure vessel design.
prex
motori@xcalcsREMOVE.com
http://www.xcalcs.com
Online tools for structural design
RE: Pressure Vessel Standards
You may want to contract an individual or firm with more experience and then get a preliminary cost quote from an ASME cetrified fabricator.
With regard to testing, the first hydro test of the vessel is done as an initial certification and must be available to the certifying inspector. Any subsquent pressure tests are doe on a periodic basis and are usually part of an OSHA required "Mechanical Integrity" program. Rather than viewing and searching ASTM sites, I suggest the following:
www.asme.org
www.nationalboard.org
www.osha-slc.gov/SLTC/pressurevessels/index.html
and there are many others....
Good Luck
MJC
RE: Pressure Vessel Standards
RE: Pressure Vessel Standards
RE: Pressure Vessel Standards
RE: Pressure Vessel Standards
If you come to my site; www.gowelding.com and follow the link for PED Directive, you will find a link to the Directive in pdf format on the UK DTI site. It's FREE to down load.
Have Fun
RE: Pressure Vessel Standards
Cheers,
akmal
RE: Pressure Vessel Standards
Why don't you start a new thread for a new question, possibly in the Boiler and PV Eng. forum?
To come to your question there is no such provision, as far as I can remember, in the ASME VIII. I suppose there is one in some of the piping B31 codes, but cannot check at the moment.
I know also that is customary to find such a requirement in many pressure vessel supply specifications.
I think this comes from the confusion between proof (structural) testing (the only one required by ASME VIII) and leak testing.
In the former the duration is unimportant, as a structural failure would occur almost istantaneously, in the latter it is, as leaks might develop over time.
prex
motori@xcalcsREMOVE.com
http://www.xcalcs.com
Online tools for structural design
RE: Pressure Vessel Standards
--Scott
RE: Pressure Vessel Standards
you can you advise on the BS for units at 0.95cc and how my company make obtain EU stamping of unit to sell in UK?
Regards
RE
RE: Pressure Vessel Standards
There is no required duration of the hydrotest given in the ASME Code. The duration is something agreed upon by the client and the fabricator. However, we have used a duration of one hour for the hydrotest. We have used this approach for many years. If the vessel is going to leak it always happens within that time.
engrdon
RE: Pressure Vessel Standards
hydrotest pressure is 1.5 times the working pressure
burst pressure is 3.5 to 6 times
hydro test time is 30 minutes
menon1946@hotmail.com
RE: Pressure Vessel Standards
RE: Pressure Vessel Standards
You can use also the AD MERKBLATT Code, from Germany, I think it is a very efficient one for pressure vessel mechanical calculations. It gives smaller thickness for the same work conditions, compared to the ASME, Section VIII. I use it in first place, unless the ASME is initially required.
Cheers
zzzo