HØVIK, Norway –DNV GL has begun the first phase of a joint industry project (JIP) to address the issues created as the diameter and water depths of submarine pipelines increase, and to improve the understanding of pipeline concrete weight coating behavior. The aim is to develop a design guideline that complements current pipeline codes and standards.
The increasingly challenging environments result in inconsistent safety margins, DNV GL said, as well as potential for over design and stringent installation requirements. Also, the current design approach to concrete weight coating is based on simple, general design requirements used in traditionalpipelines. Recent cases of concrete coating damage emphasize the issue.
DNV GL said the JIP, which is still open for participants, is relevant for pipeline operators, designers, installation contractors, and coating contractors.
Preliminary studies by DNV GL suggest that the interaction among factors such as shear transfer capacity, coating thickness, strength, fabrication method, type, location, spacing, percentage steel reinforcement and loads needs to be understood.
The JIP will lead to a rational design approach based on a quantitative understanding of concrete-coating behavior in response to external loads and the interaction between the important mechanisms and factors that influence this behavior. The first phase of the JIP will develop a design approach for pipeline concrete coating and is due for completion by December 2015. The second phase is for an experimental validation of the design approach and development of a design guideline for pipeline concrete coating. The JIP is expected to be completed by the end of 2016.
Current participants include Petrobras, Saipem,Bredero Shaw, SVAP, and Wasco Coatings.