Novel Thermal Insulation Systems for Deepwater and Arctic Pipelines Based on Styrenic Alloys

As offshore pipeline installation in deepwater and arctic applications increases, technical requirements for pipe coating and flow assurance thermal insulation are progressing along the following trends: longer design life, longer tie-back, lower U value, deeper water depth, thicker pipe wall and the more use of CRA and Clad pipes, higher operating temperatures, longer period of storage in marine environments, tougher performance and HSE requirements for application process and installation, and more comprehensive testing of coating and insulation products during process qualification testing (PQT) stage. The challenges to the pipeline industry are to improve the conventional systems or to develop new coating and insulation materials/technologies to address the new requirements, and to establish meaningful testing standards and capability to validate the performance of these improved/new coating and insulation systems (including field joint systems). The paper describes the development and qualification of a novel thermal wet insulation system for deepwater and arctic pipelines based on styrenic alloys. Compared with traditional insulation materials, the next generation of subsea flow assurance insulation system has many unique properties including unlimited water depth capacity, lower system thickness, improved cool down performance, low temperature flexibility, intermediate to high temperature ratings up to 95–120°C, and can be produced with the established extrusion processes. Results of completed laboratory and product/process validation qualification tests as well as a case study of two projects including the first ever wet insulation project in the arctic are highlighted.