Appendix A: May UT also be omitted? 1

[lpfaustini]

Dear community,

So it comes to a point where Appendix A can be used. Using E = 0.7, spot radiograpy may be omitted. But, what about UT if we're using UT instead of RT. May it also be omitted?

Thanks in advance,

 

[bernoullies123]

Sure. Both UT and RT perform the same task. They examine the weld.

620-I-13/00 refers to Table 5-2, and Table 5-2 indicates Radiographed requirements, therefore the query only referred to RT. But per Note 1, directs you to section 5.26 which confirms RT or UT which both are referred to as examinations.

 

[lpfaustini]

THAT's what I was thinking! But I can't find anywhere a text to present to our client. I'm simply saying to them:

"This is logic. If normally RT is performed, but we are using UT in lieu of RT, if App A says we won't need RT, thereafter we won't need UT at all"

But they cannnot accept my explanation

 

[fabtank]

Assuming this is an API 650 tank, here is how I would present your case:

8.3.1 When Ultrasonic Examination is applied in order to fulfill the requirement of 7.3.2.1, the provisions of Appendix U shall apply.

U.1.2c Number and Locations (see 8.1.2)
When these sections refer to radiography, for purposes of this appendix, they shall be read as applied to UT.

8.1.2.1 Except when omitted under the provisions of A.3.4, radiographs shall be taken as specified in 8.1.2 through 8.1.9.

A.3.4 By agreement between the Purchaser and the Manufacturer, the spot radiography may be omitted, and a joint efficiency factor of 0.70 shall be used.


This still depends on the contract between you and your client.
If you have previously agreed upon using a joint efficiency factor of 0.7 and omitting the radiography requirements then it is not required.
If not, then they have the option to specify a higher joint efficiency factor which requires RT or UT testing.

 

[lpfaustini]

Fabtank,

I couldn't do better.