Schlumberger

Technical Paper: How Continuous Improvement Led to the Longest Horizontal Well in the World

Society: SPE
Paper Number: 119506
Presentation Date: 2009
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Abstract

Maersk Oil Qatar AS (MOQ) completed drilling the world record BD-04A well in May 2008 offshore Qatar. This was the successful outcome of engineering efforts to increase extended reach capabilities.

MOQ started to develop the Al Shaheen Field offshore Qatar in 1994 with the application of horizontal drilling techniques, pioneered by Maersk Oil & Gas AS in the North Sea. In 1994, 10,220 feet was the longest horizontal length drilled by MOQ. In May 2008 the BD-04A well was completed with a record horizontal length of 35,770 feet. This well also set new world records for both the longest well at 40,320 feet MDRT and the longest along hole departure of 37,956 feet.

The introduction of new techniques has allowed existing constraints to be successfully challenged and overcome. This was achieved through the application of sound engineering principles and continuous optimization during the field development phases.

This case study will review the history, challenges and planning, leading through to the successful drilling of the BD-04A well. The paper will outline the achievements, improved practices and the engineering analysis of field data where key learning points have been shared for future use and applications. It will show that even when constrained by certain limitations such as rig capacity, major step changes can be achieved by optimizing basic operating parameters. In addition to the world record, several other accomplishments have also been achieved in this well as detailed in this paper by using state-of-the-art horizontal drilling technology.

The paper will not only contribute directly to the industry's knowledge base related to improving hydro carbon recovery through extended reach horizontal wells but also set an example of how operating envelopes can be extended by continuously challenging existing practices.