Where valves are concerned than ASME B16.34 gives NDE requirements for special class valves. This NDE can also be applied to standard valves. The only problem with B16.34 is that it does not cover all valve configurations and some of the drawings can be open to interpretation, it is however a very good starting point. There was also a new EN standard 12516 which was in draft format and was to include the valve configurations of B16.34 and other types not included e.g. Ball Valves.
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