Design, Fabrication and Installation of the First Ever Reeled Pipe-In-Pipe System in Offshore Brazil

Abstract

The domestic demand of gas is increasing in Brazil. Petrobras is responding to this challenge by bringing several gas fields on stream offshore Brazil. Among them is the Canapu field, located east of the State of Espirito Santo, about 75 km off the coast, in a water depth of 1608 m. The produced gas is transported using a 20 km long pipe-in-pipe (PIP) system to the Cidade de Vitoria floating, production, storage and offloading system (FPSO) located in the Golfinho field to be processed and then exported onshore through an existing gas pipeline.Technip was awarded an engineering, procurement, construction and installation (EPCI) contract and was responsible for the detailed design and installation of the first ever reeled PIP system offshore Brazil. The project was awarded on a fasttrack basis, which required design, qualification, fabrication and installation of the PIP system in less than 18 months. The scope also included two pipeline end terminations (PLET) with seven gate valves, free span rectification, the crossing of three flexible flowlines, and, pre-commissioning activities (flooding, cleaning, gauging and hydrotesting). The PIP system was also prone to lateral buckling, which required definition of a robust mitigation strategy.The design requirements for the Canapu PIP system involved the design and qualification of several technically advanced components and novelties in PIP design including the application of the first ever reelable mechanically clamped waterstop system and the use of buoyancy modules for lateral buckling management on a PIP system. This paper presents the overview of the design, fabrication and installation of Canapu PIP system as well as a summary of the qualification test program performed for the different PIP system components.

Optimising Reeled Pipe Design through Improved Knowledge of Reeling Mechanics

“…Buckle initiation techniques, such as single or dual sleepers configurations [19,20], or use of distributed buoyancy [21,22], are increasingly implemented, in order to control the severity of the buckles intentionally triggered at pre-defined locations and to avoid the appearance of rogue buckles. smoothen trench profile to reduce trench bottom out-of-straighteness).…”