Guideline tensioner

A guideline tensioner is a device used on an offshore oil drilling rig or ship which keeps a positive pulling force in the guidelines, going from the vessel to a template on the floor, independent of the movement of the drill rig or drill ship.

The guidelines act as a guidance for equipment and tools that must be lowered to the template. If there were no tensioner and the ship or rig moved up or downwards, the guidelines would become slack and/or would be destroyed.

For this reason a number of guideline tensioners (springs) are mounted between the ship (rig) and riser. Each of these guideline tensioners consists of a hydraulic cylinder with sheaves 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 is connected to the template.

On board of a drill rig or drill ship, one may find following tensioners:

*Drill string compensator
*Riser tensioner
*Guideline tensioner