AS2885.2 tiar 1

[OZWelder]

I have a pipe pipe line I am inspecting on, construction code is AS2885.2 T1. The pipe is 457mm OD and was meant to be 15.9mm wall thickness. Pipe is AIP 5L X70 grade seamed pipe. I have come into this job after 3Km of pipe has already been welded and now I have found the pipe to only have a wall thickness of between 14.8 and 14.5mm thickness. AIP code allows wall thickness for pipe over 15mm thick to have a tolerance of 1.5mm, so wall thickness for me can be as low as 14.4mm and still be acceptable to API.

My question is; if the wall of the pipe is supposed / design to be 15.9mm and actual wall thickness is 14.7mm and there is some scaring / mechanical damage on the pipe or pitting that is 1mm deep taking the wall thickness down to 13.7mm then this would call for the pipe to be rejected, also if we were to get arc strike on the we would only be allowed to blend to a depth of 0.3mm before the joint would be rejected?

Then what about under cut as the code states that under cut that is less then0.8mm deep is not a defect, there are no client specification to over rule this. and as2885.2 T1 allows 50mm of under cut that is deeper then 0.8mm. surly this to would bring the wall thickness under API allowance of 14.4mm?

 

[Dhurjati Sen]

API is applicable as far as material acceptance is concerned, be it MTC review and new piping inspection by TPI.

The construction code comes into play during fabrication. You continue following it as long as it does not violate API mandated 14.4 mm. Once it does, you need to reject, be it an undercut or a pit.

The manufacturer of the pipes has been very smart, he has saved a lot of material in this case. The ordering process has been faulty and no supplementary clauses / client requirements were added.

Do check the RFQ & PO in case there are holds and stops for the manufacturer/ vendor. If there are, apply those clauses to impose penalties / blacklist / or ask for discounts.

All the best!

DHURJATI SEN