Drilling Rig Positioning System

Drilling Rig Positioning System

A drilling rig is an integrated system that drills wells, such as oil or water wells, or holes for piling and other construction purposes, into the Earth's subsurface.drilling rig positioning system Rigs can be mobile equipment mounted on trucks, tracks or trailers, or more permanent land or marine-based structures (such as oil platforms, which are also sometimes called 'offshore oil rigs' even though they don't contain a drilling rig).

Drilling rigs can be found in almost every environment on the planet, from searing desert heat to freezing Arctic conditions and everything in between.drilling rig positioning system The rigs themselves are often ingeniously designed for specific conditions, with the most complex ones being built to drill in underwater ocean depths that can be many times greater than their onshore counterparts.

The most important feature of any drilling rig is its hoisting system, which raises and lowers the drill string and other equipment in and out of the borehole.drilling rig positioning system The hoisting system is typically located in a tall structure called the derrick or mast, and it consists of a main component called the drawworks, which uses large drums to reel in or out the drilling lines that drive the drill shaft.

In order to be able to use the same equipment on different platforms, the inventors realized that it would be necessary for the rig's positioning systems to be able to adjust themselves to the specific platform on which they are to be used. They therefore conceived of a system in which the rig's guiding elements are arranged on a separate support frame that is positioned first on the platform.

Fig. 3 depicts a view of the support frame in the side view with rig skid beams removed and the position of the rig is shown. The support frame consists of a first and second skid assembly. The distance between the first and second skid assemblies is adapted to a platform with respect to a longitudinal direction 13. The second and third skid assembly is adapted to a transversal direction 12.

A crane on the vessel that is transporting the drilling rig or on the offshore platform is used to lift and lower the rig onto the respective rig deck. After a few hours on location, the rig can then start working. In order to monitor the performance of the onboard DP positioning systems and ensure that they are within specification, an independent onshore positioning specialist performs an error budget exercise on desk-top and oversees the performance and calibration of the onboard systems during the DP trials. In addition to this, a high accuracy positioning reference system is permanently on board with the rig, consisting of 4 DGPS and dual HiPap500 USBL systems. These are telemetered to an Iridium server and displayed on a web map, enabling additional onshore QC. This approach reduces the need for a survey positioning contractor and the associated mobilisation costs, while providing an independent verification of the onboard positioning systems. It also reduces the number of manned crew required onboard.

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