Radiography for crynogenic service
Radiography for crynogenic service
(OP)
Dear all,
I have a 1/2" thk, 14' diameter 304 SS horizontal drum at low temp -290deF (-180C). Is it necessary to specify full radiography to check complete long seam in lieu of spot ? Shall I concern crack propagation from low temp to ambient vise verso such that full radiography shall be specified ?
I have seen people using full radiography for low temp, but I do not know how to justify to spend additional money.
I have a 1/2" thk, 14' diameter 304 SS horizontal drum at low temp -290deF (-180C). Is it necessary to specify full radiography to check complete long seam in lieu of spot ? Shall I concern crack propagation from low temp to ambient vise verso such that full radiography shall be specified ?
I have seen people using full radiography for low temp, but I do not know how to justify to spend additional money.





RE: Radiography for crynogenic service
RE: Radiography for crynogenic service
We also definitely performed hydrotest and not pneumatic test. Most companies that handle cryogenic fluids do a proper drying before any operating fluids are introduced.
RE: Radiography for crynogenic service
Where is the the final installation location for this vessel ?
MJCronin
Sr. Process Engineer
RE: Radiography for crynogenic service
How can you detect leaks with thermal insulation?
I suggest full RT and preliminary leak test.
Regards
r6155
RE: Radiography for crynogenic service
Hydrotest will be performed and then complete dry out, no air test. It has nothing to do with code of record or installation location, and thermal insulation is very common to vessels that does not mean it shall be full radiography.
RE: Radiography for crynogenic service
1) Reduction in thickness from E= 0,85 to E=1 : economical reason
2) See 100% RT for long and circumferential welds in “Cryogenic Handbook” http://www.tdd.org.cn/upload/2011-12/2011120952442...
3) Vertical or horizontal pressure vessel ? –wind, seismic ?
4) Vacuum insulation ?
5) Leak test . See “Cryogenic Handbook”
6) Preliminary leak test:. See ASME V . You can use vaccum box as minimun leak test in longitudinal and circunferential welds
Regards
r6155
RE: Radiography for crynogenic service