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Re: [MW:28753] Piping ID chamfer mark in RT Films

I have seen this type of situation many times in my career. This is a 'chamfer mark' left  on the i.d. of pipe / fittings after chamfering the i.d end prep to obtain the required i.d. for a good fit up. Remember, this is a 'chamfer' mark left after chamfering the i.d. end prep.These i.d. chamfering marks are sharp and will show up on the radiograph as linerar indications and therefore are 'rejectable' unless QC or RT level ll inspectors make a note on welding documentation that they have visually inspected and determined that the 'chamfer marks' exist as chamfer marks and are not rejectable. This note should be specific as how long, how far from the root they exist etc. These sharp indications should be 'lightly' buffed or ground to leave a rounded corner. This rounded corner will not show up on the radiograph if the 'sharpness' is removed. If the weld documentation is noted as above, the RT technician should 'accept' even if the linear indication shows up on the film.
Remember, linear indications will show up on the o.d. of welds or HAZ also. In these cases a simple v.t by the inspector should
be enough but I prefer complete removal prior to the RT. Welders / fitters and supervisors should be taught what will be acceptable and what is rejectable before welding.
Good Luck,
Sincerely, 
Gene Matsko


On ‎Monday‎, ‎December‎ ‎10‎, ‎2018‎ ‎07‎:‎33‎:‎39‎ ‎AM‎ ‎CST, Mohan <ggnanamalli@gmail.com> wrote:


Hi Experts,
 

The piping pre fabrication work going in HRSG piping , in which it has been found that some of the 6" pipe to elbow welding for downcomer are not satisfactory. 


When investigated it was found that pipes, which has been supplied, there are some tool mark in inner surface(refer photo).


 When the thickness measured there is a reduction of 1.25 to 2 mm in thickness and in radiography a dark clear linear indication.


Whether it's acceptable, if its acceptable means suggest code reference 

or we have cut and re-weld


Regards

G Mohanraj

 


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