API Certificate - Bend Stiffeners - Trelleborg Offshore

Bend Stiffeners are used to protect flexible pipelines from over bending at the termination point. Bend Stiffeners are suited to the constant wave and current induced motion of dynamic installations but can also be used for static applications.

Trelleborg's Bend Stiffeners Receive API 17L1 Design Review Certification

Trelleborg’s offshore operation in the UK, has been certified for a design review under the American Petroleum Institute’s specification for flexible pipe ancillary equipment (API 17L1 Ed. 1 2013), for its high performance dynamic bend stiffeners.

The review 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 material qualifications, manufacturing processes and procedures. In addition, a manufacturing audit and site visit to the company’s metal work supplier was undertaken.

Andrew Garside, Innovation and Technology Director within Trelleborg’s offshore operation based in Skelmersdale, says: “We were keen for our bend stiffeners to undergo the stringent API assessment, in order to demonstrate their ability to meet such high levels of performance. Alongside the detailed design report, we also received three other certificates for design verification, materials review and manufacture, to confirm each independent review.

Certificates of compliance
“We believe that this verification makes our bend stiffeners the clear choice for use in even the most challenging and harsh applications. We are currently in the process of putting three other products through the same review.”

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 of compliance for API 17L1 in all three areas; design, materials and manufacturing.

Product features
Trelleborg's bend stiffener is a polyurethane molding with a conical external profile and a central hollow cylindrical section allowing it to slide over the end of the flexible pipe (riser, umbilical or cable). The bend stiffener has an internal steelwork housed at its base which forms the interface between the polyurethane cone and the termination point.

Bend stiffeners are designed to ensure the manufacturers recommended minimum bend radius is not infringed during the life of the flexible pipe, umbilical or cable, preventing catastrophic failure at its termination point. The bending stiffener is also designed to transfer load via a suitable path from flexible pipe to the fixed structure. Its conical shape provides a gradual transition in stiffness, hence preventing over bending at the termination point.

Each bend stiffener is uniquely designed for its environmental application under defined tension and angle combinations