X-ray cameras have been used for welding quality control since the late 1940’s. So why is this a problem now?
Maybe it is about inefficient use of inert gases in the welding process, which means oxidation & weakening of welded joints.
I suspect it is porosity as well as cold lapse. X-ray would have picked this up upon inspection unless the inspectors were incompetent or paid to look the other way.
A nuke plant here in Texas had substituted inspection x-rays inserted into files and they got caught after the fact with post build inspections prior to start up. Cost rate payers ALOT of money to fix.
Maybe it is about inefficient use of inert gases in the welding process
or something wrong with the gases themselves, eh??