Belanak Development: Case Study of Batch Drilling Operation in Natuna Sea

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractIn October 2003, development drilling of the ConocoPhillips Indonesia Inc.Ltd operated Belanak Field commenced when the platform rig was rigged up over a previously installed twenty-four slot platform. Drilling commenced with the objective of drilling and completing ten slant directional wells and six horizontal wells.The objective of the Field development was to have high production rates available when the FPSO facilities arrived approximately twelve months later. Since the wells had to be pre-drilled before first production,it made sense to utilize a full batch drilling concept in order to minimize costs.The 13-3/8" surface casing strings were successfully batch set on all sixteen wells. This section was completed fifteen days ahead of budget time and set several world record penetration rates for a 16" tricone bits.The 9-7/8" hole/7-5/8" casing sections were batch set in ten wells. Most well objectives were met and the performance was exceptional in some wells, but, this section was plagued by surface and downhole equipment failures.The 12-1/4" hole/9-5/8" casing sections were batch set in six wells. All well objectives were met including landing all wells in the reservoir at 90 o . Time to complete this section was longer than expected due to inconsistent BHA response.The 8-1/2" horizontal hole sections were then drilled and completed with a 3,500 ft average hole length for the same six wells.This paper will focus on the drilling operations and discuss the performance and problems encountered. The Belanak drilling team was committed to continuous improvement by capturing data and immediately implementing the learning's. This commitment to maximize the learning curve resulted in minimizing cost and a successful intensive batch drilling operation.