Offshore Rig Sharing Improves Exploration Drilling Performance: A Case History

摘要

A jackup-drilling rig drilled seven exploration wells in the U.K. and Norwegian sectors of the North Sea during a twoyear drilling program. By using sublet well commitments and assignments, the rig was secured in a very tight rig market. The drilling rig was shared between two Amoco (now a part of BP) business units for four wells and another major operator for three wells. The application of rig and personnel sharing produced over 10% (U.S. $12 million) cost savings to Amoco through shared lessons learned, continuous improvement, and reduced permitting time. An additional savings of over 10% (U.S. $12 million) was achieved through detailed planning and risk assessment that significantly reduced unscheduled-event (trouble) time. Key factors for success of the program include continuous use of the same rig, crews, and offshore team members; the vision and support of management; adequate well design and pre-planning time; and the commitment of the right people with the right talents to the projects. The same Amoco wellsite supervisors were utilized throughout the program (even as the rig moved from operator to operator). This paper summarizes how the sharing of a rig, people, and best practices can improve exploration drilling performance, even across different teams, business units, operators, and countries. Examples of sharing knowledge between project teams are presented to quantify the value of a long-term drilling rig contract for one-off exploration wells. The paper concludes by providing lessons learned from rig-sharing agreements and future applications of rig sharing.