B16.34 NDE

[YBM]

In B16.34-2009 there are several Mandatory Appendices that deal with examination of castings, etc.

The only reference, in the body of the standard, to these in in paragraph 8 (Special Class Valves). However, the appendicies do not reference this and their titles contain the word, "Mandatory".

So my question is, does anyone know if these appendices apply to all valves built to the standard, or just the special class ones?

Thanks

 

[bcd]

Further explanation is in 2.1.2 and 2.1.3 where Standard and Special class are defiend.

Special class valves require the additional examination in order to qualify for the higher pressure rating.

Standard class valves can be with our without the examination of casting in the appedicies. It is optional. Not necessary. And the valves can only be rated up to the standard class pressure limit.

 

[YBM]

Thanks for your thoughts. What I am having trouble with is that I do not see any mention of the Mandatory Appendices excluding flanged or standard class valves, or being only applicable to special classes.

It is that word "Mandatory" that gets me.

 

[PeterIgg]

My understanding:
Special class is ONLY applicable to screwed or weld end valves, not flanged valves, per the reference bcd gave above. Section 8 defines the extra testing required for Special Class. Paras 8.2, 8.3 define the scope of testing. As this is only defined for Special Class the inference is that it is not required for Standard Class. The client can, of course, make his own requirements when going out to tender....

I hear what you are saying, but I think that you are trying to read too much into the standard. You could, of course, put the matter to bed and pose the question to the committe and get a ruling via the 'Interpretations' to clarify their intent.

 

[YBM]

Thanks to all, I shall do that.