Submarine Cable Bend Restrictors in Subsea Applications

Subsea cable bend restrictors (also called bend limiter) are key component to protect underwater cables from mechanical failure caused by excessive bending.They are usually used with J-tube centraliser or bend stiffener to prevent the flexible tube from abrasion and excessive bending. The following is a detailed introduction to the structure, function and application of the bend limiter.

Structural Features of Submarine Cable Bend Restrictors

• Haver structure, module interlocking connection, easy installation.

• Product density is 1.17g/cm3, close to seawater density, which can reduce additional load.

• Maintain excellent tensile, bending, impact and other mechanical properties at -10℃-+70℃.

• High-performance polyurethane material with excellent wear and corrosion resistance.

• Guaranteed 25-year underwater service life.

• The hardness of the bend limiter reaches 83D or can be customized, with strong anti-deformation ability.

• Stainless steel or super bidirectional stainless steel fasteners can be used as needed.

Functions of Submarine Cable Bend Restrictors

• Prevent Excessive Bending: Mechanically restrict the cable’s bending radius to ensure it does not exceed the manufacturer-specified minimum bending radius (MBR), thereby avoiding damage to internal components (e.g., optical fibers, conductors, and insulation layers).

• Provide Structural Support: Deliver a smooth stiffness transition at the connection between flexible pipelines and rigid structures, so as to reduce stress concentration and enhance the mechanical integrity of the joint.

• Enhance Durability: Made of polyurethane with wear and impact resistance, the bend restrictor can extend the service life of submarine cables, reduce maintenance requirements and operational risks.

• Reduce Dynamic Stress: Absorb shocks caused by ocean currents, vessel movements or cable laying operations. Alleviate fatigue induced by repeated bending in dynamic environments (e.g., floating wind farms).

Equipment and Industries for Submarine Cable Bend Restrictors

Submarine Communication Industry

Function: Prevent optical cables from excessive tension and bending during installation, or from impacts by ocean currents or vessel anchoring, which could cause breakage of internal optical fibers.

Offshore Wind Power Industry

Function: Cables in floating offshore wind farms require bend restrictors installed between buoys and the seabed to withstand dynamic loads caused by waves.

Subsea Oil and Gas Industry

Function: Connect subsea wellheads and Floating Production Storage and Offloading units (FPSO), and restrict the bending radius of risers under the influence of platform movement or ocean currents.

Jumpers

Function: Used to connect subsea Christmas trees, manifolds and other equipment over short distances, preventing accidental bending during installation or maintenance.

Subsea Control Cables (Umbilical Cables)

Function: Protect internal pipelines for power transmission, hydraulic pressure and signal transmission, avoiding damage caused by bending in high-pressure deepwater environments.

The submarine cable protection system boasts excellent wear resistance and impact resistance, the dimensions, hardness, color and length of the cable bend restrictor can be customized according to application scenarios. Choosing an experienced manufacturer is the key to ensuring the efficient progress of projects. Click to contact us for free customized design solutions and product details!