An Innovative Approach to Optimize Trunkline Cladding Requirements for an Offshore Gas Field Development
Subsea pipelines such as flowlines, trunklines etc. are an integral part of all offshore field developments. Sour service conditions as encountered by production pipelines of gas fields require CRA clad pipe due to high risk of localized corrosion initiation and penetration rate in carbon steel. This paper presents an innovative approach to optimize cladding requirements of trunklines of an offshore gas field development. This approach involves removal of concrete coating from flowlines as well as from cladded section of trunklines for enhancing fluid cooling. The cladding length of each subsea trunkline was significantly reduced as compared to concrete coated case. The impact of removal of concrete coating on other disciplines required minor modifications which were outweighed by the reduction in trunkline cladding. The proposed approach was successfully applied to reduce cladding length of two subsea trunklines by more than 70% which resulted in significant cost savings and project schedule improvement.