UT in lieu of RT?

[qcrobert]

Have a vessel, non lethal service, non code stamped, that was designed per Sec VIII Div 1. Client wants spot RT to fullfill 85% joint efficiency. I, as manufacturer, have proposed 100% shear wave UT to give overall better information on all weld seams. Client agrees but wants me to provide evidence that 100% UT will fullfill Code requirements of 85% JE.

Do not have 2010 edition with me at this time. CC-2235-6. Code Case 2235 permits the use of UT in lieu of RT at any time, under the qualifying conditions of the Code Case. In other words, the Case allows for the substitution of ultrasonic examination in lieu of radiographic examination for all welded seams in a vessel that require examination.

I know this requirement does not exist in the 2008 Edition Code.

In the ASME Sec VIII Div 1 2010 Edition, has this Code Case been adopted and incorporated? And would this fulfill 85% JE req?

PS Need amunition for use of UT in lieu of RT...

Thanks for you help,
QCRobert

 

[normet]

The 2010 edition of ASME VIII-1 does not allow for UT substitution for RT for other than checking a repair and in this case the UT must first confirm the RT finding.

I think it unlikely that the Code Committee will accept UT in lieu of RT any time soon, as the AI can look at a film, but understanding UT data can require a specialist. Right now you are stuck with the Code Case, and it is not necessarily cheap to implement given the requirements to qualify the UT procedure and examiner.

 

[qcrobert]

Thank you normet for your quick and concise reply!

 

[metengr]

Non-Code stamped, you can do as you please.

 

[qcrobert]

Yes metengr, I agree but Client wants to know if 100% UT will satisfy Sec VIII Div 1 code requiremnt that 85% joint efficiency has been achieved.

Unfortunately by Code I don't see that it has.

Comments?

 

[weldtek]

I have a very large job going on presently where we're applying CC2235-9 and I can tell you with certainty that there's no way it would be a cost effective alternative to RT-3.

 

[metengr]

qcrobert;
It makes no difference what the Code committee would accept because this is a non-code stamped vessel and cannot be stamped after the fact. In other words, this vessel will always remain as a non-code stamped vessel.

Now, with that being said, I would say ultrasonic examination is more sensitive and would be in substantial compliance with VIII volumetric examination requirements.

 

[qcrobert]

Weldtek,

The cost of RT at our remote location is $1,300 min, for 1 shot (6" of coverage).

Cost of UT is $72.00/hr, 4 hr min, (288" of coverage).

I am trying to save the end Buyer some money and also insure the best coverage and weld quality assurance.

We charge examination cost + 10%.

 

[vesselfab]

give him the estimated cost for both and let him decide

 

[weldtek]

qcrobert,
Manual UT shear wave alone will not satisfy CC2235. For reference, we're paying over $2000 / day for the crew. The qualification block alone for our project was over $ 10,000.

 

[qcrobert]

Weldtek, quite the project you have going on!

These are 2ea simple designed Vapor Belts, 14'x25'x8' 5/8"-1/2" thk.