Key points are not available for this paper at this time.
Abstract Objectives/Scope The Mumbai High field located in the Western offshore of India poses significant challenges for drilling and liner running operations due to reservoir depletion and severe lost circulation conditions. As a result, a pilot project was implemented to address these difficult carbonate reservoirs using a new technology called Liner while Drilling. The operator had previously encountered substantial losses in the zone, resulting in significant rig downtime and damage to the reservoir caused using Loss Circulation Materials (LCM) Pills. Methods, Procedures, Process To overcome these challenges, the Steerable Drilling Liner service was employed, which combines a rotary steerable system and Logging while drilling tools with a liner. This innovative approach helps in drilling through zones with lower pressure and unstable shale/coal layers, as well as formations with varying flow and pressure conditions. The integrated Bottom hole Assembly includes an Underreamer to enlarge the drilled hole, enabling the liner to cover the open hole portion during the drilling process. It is worth noting that drilling with a mud motor and low RPM from the surface puts less stress on the formation compared to conventional Rotary Steerable Bottom Hole Assembly (BHA). In the second run, cementing is performed with the assistance of a cement retainer assembly. Finally, in the last run, a Completion Packer and Liner Hanger are set to hand over the well to the operator. Results, Observations, Conclusions The use of special mud additives and Liner while Drilling technology effectively contained losses. The plastering and smearing effect across the wellbore provided value in addressing the losses. This technology reduced formation damage by eliminating the need for repeated LCM pills. The Steerable Drilling Liner service helps mitigate the risks of hole collapse and formation damage by reducing exposure of the open hole section, minimizing non-productive time (NPT) by eliminating extra trips, and ensuring that the liner is installed at total depth (TD) during the first run. Novel/Additive Information This paper will provide a detailed discussion on the application of Liner while Drilling technology in the Indian Western Offshore Field. It will cover lessons learned from two deployments, opportunities for improvement, and the way forward. Additionally, the paper will examine the execution of the technology in two specific wells, addressing the challenges associated with each well and the methodologies employed to overcome them.
Bagga et al. (Thu,) studied this question.