The curvature limiter is a tubular member that is suitable for adopting a straight position or a variable curvature position, thereby allowing the flexible submarine pipeline inserted into the tubular member to achieve a controlled variable curvature or no curvature while preventing the curvature radius from being less than a given minimum curvature radius R0. The following is a detailed introduction to submarine pipelines and the characteristics and applications of curvature limiters.

What is submarine flexible pipeline?

Submarine flexible pipeline refers to a pipeline that is easy to bend and has a minimum curvature radius of several meters, especially in the range of 0.5 meters (m) to 5 meters, while remaining within the elastic range. Such flexible pipelines can be:

a) A flexible pipe for transferring a petroleum fluid, conventionally constituted by an internal tube of flexible polymer material reinforced by braided composite or metal wire reinforcement forming spiral-wound sheaths;

b) Pipes or cables for transferring energy or information, such as electric cables, control cables, hydraulic fluid transfer pipes feeding hydraulic equipment such as actuators, or pipes containing optical fibers; 

c) Umbilicals, i.e., pipes made up of a plurality of such electric cables, hydraulic pipes, control cables, and/or optical fibers.

Features of bend restrictors

a) Avoid excessive bending of submarine cables and pipelines.

b) Two-piece split interlocking design, easy to install and replace a unit.

c) Polyurethane material is more wear-resistant, impact-resistant, chemical-resistant, and UV-resistant.

d) Service life can reach 25 years, reducing maintenance costs.

e) Length, hardness, and size can be customized.

Applications of curvature limiters

The technical field of the curvature limiter is more particularly the field of fabricating and installing production riser columns (or “risers”) for conveying oil, or gas, or any other soluble or meltable material, or a suspension of mineral materials, from an underwater well head to a floating support to develop production fields installed off-shore, out at sea. The main and immediate application of the Submarine flexible pipelines is in the field of oil production.

Philson has more than 25 years of experience in polyurethane products and dozens of raw material formulas. It can be formulated and cast into high-quality polyurethane bend limiters according to actual needs. There is test equipment inside the factory to verify the breaking moment of the bend limiter according to customer specifications. Feel free to contact us if you need any help!