Modern Mobile Offshore Drilling Units (MODU) are equipped to ensure they are able to cope with the demands of both current and future offshore well design challenges which may be located in either in deep water or inmature basins like the North Sea thatrequire significant measured depths to reach the intended target. With all of this drilling power, such as topdrives capable of producing over 75,000ft-lbs of continuous torque and multiple mud pumps each with the ability to flow in excess of 1,000gpm it is readily possible to damange the wellbore by over using the available capacity of the rig. In reality this surfeit of available energy, if not used judiciously, can potentially result in unexpected problems.

Much has been written in the past with regards to ensuring that the available rig capability is best utilised to achieve complex well objectives and a great deal of the techniques developed in extended reach and complex well drilling operations were designed to make the most of the capacity available. Now, with high specification rigs these techniques identified originally in the early to mid-1990's, though still valid need to be used with care and consideration since the rig capabilities have advanced significantly such that without a degree of caution it is possible to cause significant damage to the downhole tools or wellbore and potentially loose either the section or the well altogether. Whilst many of the techniques often termed ‘good oilfield practice’ are still valid there are now additional considerations which have to be incorporated into both the well plan and the day-to-day operations on the rig to ensure that best use can be made of the rig's capability.

This paper aims to show how one operator successfully used a modern, high-specification jack-up rig to access a remote reservoir where challenging drilling conditions presented a number of potential obstacles to achieving the well objectives.

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