New compliant clamp technology

Louise Davis

Advanced Insulation has launched a new range of distributed buoyancy modules (DBMs) featuring the company’s latest integrated clamping technology. 

DBMs are designed to reduce tension and load strain on subsea risers and umbilicals, which act as a connecting interface between static structures on the seabed and dynamic floating structures on the surface. Insulated or multi-layered subsea risers have softer outer surfaces, so traditional clamping methods that use stiff/rigid materials cannot grip without slippage or, through the use of higher clamping forces, damage the riser itself. 

Advanced Insulation’s new range of DBMs feature an innovative clamping technology that is designed to adapt to the specific needs and conditions of a riser’s operation and eliminate slippage throughout its operational lifespan. The new internal clamping mechanism consists of three segments housing nine rubber inserts, which innovatively increase the surface contact area at the interface between the riser and the DBM. Vertical bar retainer rubbers then ensure that there is no drop off while the holding bolts are engaged, which also secures the clamp element orientation and ensures that the clamp cannot misalign around the riser body. This innovative clamping interface allows Advanced Insulation’s new DBMs to be deployed where traditional solutions would often fail and also results in a smaller, more efficient clamping solution.

Guy Downie, from Advanced Insulation, states: “Rate of installation has been a major factor in the design of this DBM system, which promises to deliver significant gains in speed and reliability for the installer.”

He explains that fastener cover clips protect fixings and prohibit the growth of damaging marine life, prolonging the module’s working life. Filled with specific grades of syntactic foam, cylindrical buoyancy or ballast modules fit around the clamp and are secured using heavy-duty Kevlar straps. Various foam densities are employed in order to achieve a specific buoyant ‘upthrust’ that is suitable to survive the required operational water depth and field service life.

The ability of this system to be connected in a modular configuration allows for single, double and triple solutions based on a proven reliable standard. Each Advanced Insulation distributed buoyancy module is designed specifically to suit a customer’s requirements and features a robust, highly durable exterior design that is low maintenance and easily installed.

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