Publications

Advances in drilling equipment, drill bit design and PDC cutter technology have resulted in significant time savings through increases in penetration rate and the entire hole section being completed in a single bit run. However, the wellbore condition has become an important consideration as the time spent to improve the quality of the wellbore to facilitate tripping and running casing is increased. The paper discusses a case study in the Jatiasri and Akasia Bagus fields, West Java, Indonesia where both the 17 ½-in. and 12 ¼-in. hole sections are considered challenging. Pipe stall, overpull, stuck pipe, and tight spots are typically experienced both during drilling and tripping, resulting in difficult trip-out and subsequent trip-in with casing. Those two case studies describe the phenomena of poor bore hole condition, which is related to micro-doglegs or tight hole issues. A unique bi-directional eccentric reamer tool called dogleg reamer (DLR) was introduced to help improve the wellbore quality. The tool removes or smooths out irregularities in the wellbore geometry during drilling and reaming operations. The runs results showed significant time saving in pulling out of hole by 38 to 91% in the 12 ¼-in. section and 20 to 57% faster in the 17 ½-in. section compared to the offset runs. In addition, wiper trips can be eliminated or greatly reduced, and casing speed is also improved. The casing shoe was also set or landed close to the designated depth, eliminating the need for dedicated cleanout runs. For more than 17 runs, the performance showed consistency in time savings while reducing the potential for stuck pipe, string stall and tight spots.
This dogleg reamer has added a new capability for drilling improvement and optimization through borehole conditioning, reducing both non-productive time and interval costs.