This paper describes a case history of an innovative completion design and performance evaluation of a high-productivity subsea gas well in Conoco's Tembang field in the West Natuna Sea. Several completion challenges were overcome to ensure a high-deliverability completion in a thick, highly-laminated, loosely consolidated sandstone interval. The need for reliable high flowrates, high inflow area and effective sand control were the driving factors in the completion design and hardware selection. In addition, expected high fluid loss rates and gas migration were other factors affecting the design of this completion from a semi-submersible rig. A single-trip perforating and packing system was utilized to minimize fluid loss and formation damage during the completion operations. A fracpack was designed to optimize the connectivity between the multiple sand layers in conjunction with alternate path technology which provided the best option for sand placement and reducing the risk of a pre-mature screen-out in the long and highly deviated interval (322 ft MD at 50° inclination).

Evaluation of both pre-fracpack and post-fracpack reservoir and well performance results were performed. The use of a pre-fracpack surge, limited influx, and an injectivity test were chosen due to well control concerns related to completing and flow testing the well with a single-trip perforating and packing system from a semi-submersible rig. Post-fracpack flow testing to the rig immediately after the completion and subsequent production tests were evaluated to determine the well performance with time and effectiveness of the completion technique. These results, along with observations and challenges from the completion operations of the Tembang 4 well, are provided in this paper.

You can access this article if you purchase or spend a download.