The certificate was completed by global engineering, technical and business services organization, Lloyds Register EMEA, acting as an independent verification agent. It was evaluated alongside Trelleborg’s product range drawings including dimension tolerances, manufacturing processes and procedures for polymer components. In addition, a manufacturing audit and site visit to the company’s metal work supplier were undertaken.
Andrew Garside, Innovation and Technology Director within Trelleborg’s offshore operation based in Skelmersdale, says: “The API assessment is a detailed process, which put our manufacturing practices of bend restrictors under stringent analysis. Receiving the certification demonstrates the performance of our bend restrictors, especially for use in challenging and harsh sea environments.”
API 17L1 is an industry standard that determines the minimum requirements for the design, material selection, manufacture, documentation, testing, marking and packing of flexible pipe ancillary equipment. Trelleborg’s offshore operation now has certificates for API 17L1 for bend restrictors and bend stiffeners.
Trelleborg's bend restrictors are used to protect flexible pipelines from over bending and buckling during their installation or operation phase where static loads are generated. The system comprises a number of interlocking elements that articulate in three dimensions when subjected to external loads. At a designed radius, the elements mechanically lock to form a semi rigid curved structure that will prevent further bending.
As bend restrictors are designed to ensure the manufacturers recommended minimum bend radius is not infringed during the life of the project. The elements also provide a significant further benefit as their split design allows installation of the restrictor after pipe termination, meaning installation and maintenance is much simpler and more cost effective.
Each bend restrictor is uniquely designed for its environmental application under defined loading conditions. With over 20 years of experience of manufacturing this product, Trelleborg has performed a significant amount of load and destructive loading tests enabling the company to fully understand the behavior of completed strings and the impact, if any, of differing element geometries. Trelleborg’s combined extensive manufacturing experience and testing of bend restrictors enabled them to build in the required safety factors into their design process.