Its Not All A Bed Of Roses Let’s face it, there are a multitude of ways to protect cables and flowlines along the seabed ranging from trenching to sheathing through to rock dumping, etc., but let’s take a step back for a moment and ask why protect them and what are we protecting them from. Again a number of reasons spring to mind from protection from trawling to dropped objects, etc.; but what do you do when none of all the available solutions suffice? This was the dilemma faced by Petrobras not too long ago. Petrobras, a committed user of Uraduct®, a half shell cable protection system, found that in the ultra deep waters of the Campos Basin region (offshore Brazil) there was a common occurrence of Coral reefs. Dead coral, with its razor sharp fingers abrades the outer sheath of unprotected flexible pipes and umbilicals in a matter of months. For several years, Uraduct® has been fitted with its specially developed abrasion resistant PU shells and Inconel banding, boasting high tensile strengths and suitability for long term sea water immersion. A concern remained with the
by Scott Griffith
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standard Uraduct® design in that the exposed metallic banding would also be prone to abrasion. A solution had to be found that still allowed the flexibility to fit an enhanced protection system in specifically targeted areas, but would not compromise the installation time or costs and would be ecologically friendly. CRP commenced a three-year development and qualification program specifically aimed at addressing this problem and meeting all of Petrobras’ stringent requirements. The coral would abrade very hard materials yet would tear softer more pliable ones, and would regenerate around the pipe or cable, leading to an exhaustive supply of abrasive material; hence the potential for proportionately short life spans of the unprotected flowlines and umbilicals. In turning internally to its R&D laboratories and bringing in external expertise in the form of marine biologists, CRP evaluated numerous materials with varied properties testing each variant in specially built abrasive