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Up Topic Welding Industry / Inspection & Qualification / Spot/Random radiography
- - By qaqcmpm (*) Date 11-17-2008 07:29
where I can look for the informations about spot & random (10%, 20% etc) radiography. T joints (conn between long seam & cir seam) shall be included or they will be additionally/compulsory in case of spot/10% RT?
Parent - By hogan (****) Date 11-17-2008 15:52
qaqcmpm,
If you could give a code reference I'm sure you will get more responses.
Parent - By G.S.Crisi (****) Date 11-17-2008 17:54
Common practice is is to RT all the T joints and make an additional radiograph between two adjacent T joints, both on the longitudinal and the circumferential welds. The location of this latter radiograph will be decided by the client's inspector.
At least that's how I used to do back in my days of erector engineer, working under the supervision of top class engineering companies like The Lummus Co., M.W.Kellogg, Japan Gasoline Co. (JGC), Repsol and others.
Giovanni S. Crisi
Sao Paulo - Brazil
Parent - - By Joey (***) Date 11-18-2008 02:07
The following may able to provide answers.

1.   Contract Specification
2.   Code (eg. ASME B31.3 Cl 341.5.1 ; ASME VIII UW-52 ; API 650 Sec 8 etc.)
3.   Approved RT procedure 
4.   Project Engineer's Instruction
5.   Client's / TPI request

Best Regards
Joey
Parent - - By 803056 (*****) Date 11-18-2008 05:30
It depends on the applicable welding standard and project specifications.

Al
Parent - - By Joey (***) Date 11-18-2008 08:51
Al

Agree, and it also depends on the requester who pays for the test, which sometimes exceeded the requirement stated in applicable welding standard and project specification.

If this is the case, will you agree with me that the contractor has to repair those defective welds detected by the extra shots (RT) which are not covered by the test frequency mentioned in the project specification / or applicable welding standard?

Best Regards

Joey
Parent - - By 803056 (*****) Date 11-18-2008 13:57
Sorry, it depends on the applicable welding standard.

As an example: D1.1 states that the costs incurred by additional NDT requested by the "owner" after the contract is signed is at the "owner's" expense unless it can be demonstrated that the unacceptable conditions are the result of an attempt to defraud or gross neglegence by the contractor. Those costs include handling, preparation for testing, testing, and the cost of repairs of unacceptable conditions discovered by subsequent NDT.

The kicker is, any unacceptable conditions detected by NDT have to be addressed once they are discovered.

Best regards - Al
Parent - - By Joey (***) Date 11-19-2008 08:47
Al

thanks for useful information.

Best Regards
Joey
Parent - By ndeguy (*) Date 11-19-2008 11:55
qaqcmpm

Here is a link to an article I found very useful for explanation of random radiography requirements.

http://www.thefabricator.com/TestingMeasuring/TestingMeasuring_Article.cfm?ID=1129

For spot radiography you really need to begin with Table 2.3. of ASME VIII Div 1 and work your way through from there.

Cheers

ndeguy
Up Topic Welding Industry / Inspection & Qualification / Spot/Random radiography

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