Tensionleg

Tensionleg refers to a type of offshore oil and gas platform that is tethered to the seabed by tensioned tendons. These tendons are typically steel pipes or cables that are kept in tension by the buoyancy of the platform itself. This tension provides stability, allowing the platform to remain in a fixed position even in deep water and harsh weather conditions.

The design of a tensionleg platform involves a buoyant structure, usually a hull or column-pontoon system, which floats on the surface. Connected to this buoyant structure are vertical or angled tendons that are anchored to the seabed. The buoyancy of the platform is greater than the weight of the tendons and the forces acting on them, creating a net upward force that keeps the tendons taut. This constant tension limits the platform's vertical movement, effectively mooring it in place.

Tensionleg platforms are particularly suited for deepwater environments where traditional fixed-bottom structures are not feasible or economically viable. Their ability to resist wave and current forces makes them a stable platform for drilling, production, and processing of oil and gas. The vertical compliance of the tendons also allows them to absorb some of the motion, reducing the impact of wave action on the platform. Early tensionleg platforms were developed in the 1980s, and the technology has since evolved to accommodate increasingly challenging offshore conditions.