This paper introduces a forensic workflow that can be used to link drill-bit and bottomhole assembly (BHA) damage to drilling dysfunction. This paper will also discuss the data that should be collected and how it should be processed to enable operational practices and engineering design changes to address these issues.
There is a vast amount of data collected in all drilling operations that can be used to improve performance if utilized within an effective forensic workflow. Several drilling forensic case studies were developed and critically reviewed by subject matter experts from across the industry. From the causal analysis for each case study, an assessment was performed on what information was (1) available, (2) required to diagnose the cause, and (3) not available but would have been preferred. The way the team communicated and acted on the data was also documented.
By combining the learnings from these case studies, it was observed that a guided approach can improve data collection and lead to a more consistent, accurate, timely, and causal analysis with appropriate remedial actions. The process discussed within has been refined to support data collection for forensic analysis and provides a reference for field- and office-based drilling professionals. These practical guidelines have been developed to offer a foundation for a drilling forensic data collection methodology as well as training for the industry—they have been created such that they can grow organically and will form part of the International Association of Drilling Contactors (IADC) Bit Dull Grading Recommended Practice to support the IADC dull grade manual. In the future, these can be used for developing subsequent industry publications.
The work described in this paper is part of a joint IADC/Society of Petroleum Engineers industry effort to revise the IADC dull grade manual.