Repair of Polypropilene Shrink Sleeves

[perruolo]

Hi Guys

Currently we are facing a big problem with our Client which complained about low thickness of epoxy primer. Pipeline factory coating is 3LPP and we are applying Polypropilene Shrink Sleeves on weld joints. Execution steps are:
1.- Surface preparation grade 2 1/2 - 50 microns roughness
2.- Preheat 60 °C induction coil
3.- Apply Epoxy primer force cured - minimum DFT 100 microns
4.- Epoxy force cured at 170°C - Induction coils
5.- Installation of Polypropilene Shrink Sleeves

We already apply shrink sleeves in a section of 150 km without any inconvenient. However, suddenly we change our usual application procedure and after 4 days of production we realized that epoxy layer thickness was 50 microns below required. Client rejected roughly 250 joints arguing low epoxy thickness. We went through supplier technical assistance but it was not enough to convince our Client.
We are trying do not remove Shrink Sleeves which is very hard and will affect 3LPP factory coating as we have to apply heat.

Is it possible to install a second shrink sleeve over the first? is this proposition feasible and technically correct?

Waiting for your advises

Regards
MP

 

[brimmer]

How would you get the second sleeve overtop to adhere sufficiently to the first sleeve? It is a smooth surface. If I was the operating company no way I would accept that, good luck.