Collaboration and Communication Lead to Continuous Improvement in 8 ½-in. Bit Design and Improved Drilling Efficiencies in Changbei Horizontal Application

Abstract

In the Changbei gas wells of China, one of the biggest potentials for savings is in 8 1/2-in. dual-lateral horizontal drilling through the hard abrasive reservoir sandstones known as the QA sandstones. Tungsten carbide insert (TCI) roller cone bits are preferred and focus was placed on increasing distance drilled per bit. The objective of the Changbei team (a joint venture between an NOC and a major international oil company) was to achieve 375 m instead of the average 250 m, saving two bits and two trips over the 2000-m interval yielding an approximate cost saving of $100,000 USD. Due to the team's continuous performance improvementdriven culture, performance stagnation was not an acceptable risk the team was willing to take.To address this challenge the bit service company worked closely with the operator proposing a two-pronged approach:1) A product solution that would meet the current performance benchmark and challenges.2) Implementing a development plan to provide continuous improvement to meet future goals.With no time for trial and error, a cross-functional team from multiple countries worked quickly developing a solution for the operator to drill the required distance at a good rate of penetration (ROP) on the first attempt. This success would not have been possible if not for the collaboration with the operator. Open access to offset dull bits and data, and clear communication of expectations and challenges were keys in delivering performance quickly.This paper provides details of the technical aspects of the product that met the current drilling benchmark. This paper also describes the Changbei team interaction between the operator and bit service provider that led to the quick solution and the longer term development plan for continuing success.