Corrosion is a costly issue in the oil and gas industry as maintenance linked to corrosion is estimated at more than $1.3 billion per year according to NACE international. This also affects tertiary steel (pipe supports, cable trays, stairs, handrails) whose maintenance can become challenging and expensive when located in offshore flammable/explosive environment such as Floating Production, Storage and Offloading (FPSO) platforms. A repair of tertiary steel on top of Crude Oil Tank needs hot work permits and may lead to production disruption. Hence, the tank needs to be emptied, cleaned and inerted and paint touch up may be required after the hot work repair. FPSO operators have then shown their interest in “cold work” solutions for fastening that could be implemented in the general maintenance instead of planned shutdown. One of the other advantages of bonded fastening is that, contrary to welded supports, it does not have a detrimental footprint (i.e. residual stresses, Stress Concentration Factor, Heat Affected Zone) on the substrate it is bonded to. Bonded fastening is used in various industries like aeronautics, but its nominal capacity is rarely above hundreds of kilograms and it is preferably installed in controlled atmosphere as humidity has a detrimental impact on bonding.

In this paper, a key product for an innovative cold solution that can be used for tertiary steel maintenance as an alternative to welding tertiary steel supports on FPSO platforms or other oil and gas industry plants like refineries and petrochemical plants will be presented. This new product, called C-Claw, is a bonded mechanical fastener with a guaranteed nominal mechanical capacity and that can be used with no compromise on safety and durability. The way this innovative technique has made it possible to marinized bonded techniques even in critical stages like installation and in-service life in harsh environments such as offshore conditions will be then described. The installation process under vacuum of this fastener and the unique protection of the adhesive in an encapsulated volume make the C-Claw bonding durable and reliable. The experimental results of mechanical tests carried out with IFSTTAR (Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux) to characterize the short and long-term performances of C-Claw will be presented and compared with numerical analysis. Finally, some applications like the maintenance of handrails and pipe supports will be shown. The performance, safety, planning and economies at stake will be compared with welded solutions.