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16:25 May-07-2009


NDT Inspector,
Royscan engineering pte ltd,
Joined May 2008
Jack up rig

we have to check the "Chord to Rack" full penetration joint with UT. Pls suggest to me to do the better inspection. Thickness of chord is 95mm and rack thk 210mm.
suggestion will be appreciated.

16:56 May-11-2009
Re: Jack up rig In Reply to Gowrisanthosh at 16:25 May-07-2009 (Opening).


I have done a few type of joint as mentioned, But the thickness of chord used to be from 34 to 40 mm. I have not heared about the 95 mm thick chord.

In our case we used a 22*20 mm crystal 45 degree & , 70 degree 8*9 mm Krautkrammer probes between 0-1 skip.



20:41 May-11-2009

John O'Brien

Consultant, -
Chevron ETC ,
Joined Jan 2000
Re: Jack up rig In Reply to Gowrisanthosh at 16:25 May-07-2009 (Opening).

Structural codes generally apply in this application look to AWS D1.1 or API RP 2X for guidance.

02:08 May-12-2009
Re: Jack up rig In Reply to John O'Brien at 20:41 May-11-2009 .

you need to be certified to UT TKY API RP 2X specs to carry out this particular job.

Anyway, a 45,60 and 70 degree with a lower frequency and a large diameter probe is appropriate enough to carry out a UT inspection on this thickness.

A Full scan (full skip with a 45 and 60 and a half skip with a 70) is carried out on the chord section. And a 45 full skip scan is carried out on the Rack section particularly looking for toe and root cracks


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