A guideline tensioner is a

hydropneumatic Hydropneumatic devices (or hydro-pneumatic devices) are systems that operate using water and gas. The devices are used in various applications. Description A hydropneumatic device is a tool that functions by using water and gas. ''Hydropneumati ...

device used on an

offshore drilling rig An oil platform (also called an oil rig, offshore platform, oil production platform, etc.) is a large structure with facilities to extract and process petroleum and natural gas that lie in rock formations beneath the seabed. Many oil platforms w ...

that keeps a positive pulling force on the guidelines from the platform to a template on the seabed. The guidelines act as a guidance for equipment and tools that must be lowered to the template. If there was no tensioner and the platform moved, the guidelines would become slack and could be broken. For this reason a number of guideline tensioners are mounted between the platform and riser. Each of these guideline tensioners consists of a

hydraulic cylinder A hydraulic cylinder (also called a linear hydraulic motor) is a mechanical actuator that is used to give a unidirectional force through a unidirectional stroke. It has many applications, notably in construction equipment ( engineering vehicles ...

with

sheave Sheave without a rope A pulley is a wheel on an axle or shaft enabling a taut cable or belt passing over the wheel to move and change direction, or transfer power between itself and a shaft. A pulley may have a groove or grooves between flan ...

s at both sides. The cylinder is connected to one or more high pressure gas bottles via a medium separator. A wire rope is rigged in the cylinder; one end is connected to the fixed part of the tensioner, the other end to the template.

References

Petroleum production Drilling technology {{engineering-stub

See also

References