This is an old report but worth sharing again.  We do not accept materials of China origin for any pressure vessel fabrication and many of our Clients spec out that no Chinese materials will be accepted for the fabrication of even non-stamped code pressure vessels.

Pressure Vessel Failure during Hydrotest-Nov. 2007 in China

January 9, 2008
Thomas Eun
Folks,
Please find attached photos of a pressure vessel that recently failed whilst under hydrotest during post
fabrication testing. This vessel was manufactured by a vessel vendor in China and the plate was of
Chinese mill origin. Unfortunately this is another example of serious equipment/material failures with
equipment being sourced out of the rapidly developing economies such as China, Eastern Bloc and
others. These examples are becoming almost a weekly occurrence now and are exhibiting failure modes
not seen in the mature manufacturing economies since the 1930's. Again we need to ensure vigilance in
the acceptance of manufacturers and once more I stress the need to know where the base materials are
sourced from.
Apparently this pressure vessel had reached fifty percent of the required test pressure when the shell
ruptured. A metallurgical failure report is not available however from the photographs a number of
observations could be made regarding the quality of the material and the welding.
Lesson learned
(1) All base metal requirements shall be specified in P.O Requisition per project/Industry Code
requirements.
(2) Consult specialists (i.e., Materials and Corrosion Engineers) whenever you doubt.
(3) All inspection (from base materials to final products) should be performed per the codes, specs &
standards.
(4) Especially when you selected the manufacturers in China, the above (1), (2) & (3) will be a very
important message.