Is non-destructive testing required for spliced liners in liner flanges?
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Due to some waste generated when fabricating the entire ring, it is more feasible to divide the backing ring plate of the backing ring flange into four equal parts for assembly. Is non-destructive testing required for their joints? Where are the relevant regulations?
This post was last edited by wxd9017 on 2022-2-8 at 13:43. Clause 4.0.3 of HG/T20592-2009 used to contain relevant provisions, but an erratum was later issued which removed those four original provisions. However, non-destructive testing of the welded joints in the clad joint should be a basic requirement. Moreover, where does the maximum allowable operating pressure value for this flange come from?
No need. There will be a leak test later on; it’s sufficient to be able to apply pressure
Refer to section 6.6.4 of nbt47020
No requirements were specified for the seams, but I personally think it’s better to carry out some non-destructive testing; even PT would suffice
The gasket is only responsible for corrosion resistance; it does not contribute to the strength. Surface testing should be sufficient, as long as there are no unacceptable defects on the sealing surface
Non-destructive testing must be done; at the very least, penetrant testing.
If intensity calculation is involved, then flaw detection is required； If intensity calculation is not required and it is only used for corrosion protection, the situation with paint can be used as a reference.