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Drilling complex wells with minimum risk and optimizing well placement with the least possible cost are key goals that oil companies strive to achieve. Service companies and operators apply several pre-well planning processes and methods to enhance drilling operations effectively and attain objectives. One of these processes involves a thorough understanding and application of the geological structure, not only within the reservoir section, but also in the over-burden where typically most of the time efficiency gains can be achieved. This can be best accomplished by fostering intense and effective communication between all stakeholders. In this paper, the authors present the latest integrated pre-well planning (IPWP) process that defines a methodology for conducting a formal planning, a process incorporating all aspects of drilling, well design, formation evaluation, bit selection and bottom hole assembly proposal. It also lists key considerations required in planning, coordination, and successful implementation of these services on the customer’s well with a means to assess potential technical risks that may influence the success of the job. The paper also describes a complex water injection well drilled in a Middle East onshore field where the integrated pre-well-planning process played a significant part in successfully achieving the aim of this challenging job.

Recently in Saudi Arabia, a national drilling record was reached for the longest horizontal well drilled. A key technology for drilling such wells, which typically show a Total Depth (TD) in excess of 30,000 ft, was the use of extended reach horizontal drilling. Drilling these wells required, among other things, a proper selection of drill stem products. With drill pipe accounting for most of the string length, choosing the right specification plays a huge role in overall drilling performance. With a lot of friction as the string is ran downhole, the ability to transmit torque to the bit is challenging and connection technology becomes critically important. Double shoulder connections place connections at par with the pipe body in terms of torque capacity and actually come with additional benefits. Not only do these connections transmit higher torque but they do it using a thinner steel envelop, which allows a larger internal opening for improved hydraulics. Furthermore, these streamlined connections can also come with reduced Outside Diameter (OD) tool joints which help keep the Equivalent Circulation Density (ECD) as low as necessary to maintain formation integrity. Towards the end of 2010, a national record 32,136 ft measured depth well was drilled in Saudi Arabia using such connection technology, proper material grade selection and optimized pipe size selection. The well was then used for horizontal water injection into the reservoir in order to maintain reservoir pressure and optimize production. This paper will describe the challenges of this project and how connection technology, engineered material grade and pipe size helped address each of these challenges. The record well case history will form the base of this paper and authors will include a comprehensive section on the successfully selected connection, its performances as well as a summary of more recent results.

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One of world's longest cemented 7″ turbine reaming liners, 5.1 km long, was successfully deployed in the Manifa field located in Saudi Arabia. The 7″ liner was effectively aided in reaching the liner point (LP) below the 9⅝ casing using turbine reamer technology installed at the end of string and was then successfully cemented. The reaming operation was performed by activating the turbine reamer shoe by pumping drilling fluid when a borehole restriction was encountered while running in the hole (RIH). The turbine reamer is a high speed reaming tool and the main benefits of using this technology in such a long horizontal section is to ream and remove obstructions (debris, cuttings, ledges, excessive filter cake) and successfully deploy the liner to the target depth (TD). The process of utilizing the turbine reamer technology to deploy the 5.1 km liner to the TD was successfully executed in a horizontal producer well in the Manifa Increment Project, resulting in reduced risk of stuck casings and liners. This paper will present a case study of the turbine reaming operation, lessons learned and challenges encountered during the running and cementing the 16,758 ft (5.1 km) of a 7″ liner in the 8½″ hole section. It also provides focus on potential enhancements for future utilization of the technology.