For Industry Review | DACC IRP Volume #1 – Critical Sour Drilling
This update reflects a targeted review of Section 1.9 (Drill String Design and Metallurgy) to modernize drill pipe grade specifications and align with current industry standards. Drill pipe grade specifications were substantially revised to incorporate higher-strength grades now widely available from manufacturers (e.g. SS110, SS125, and SS135), with additional expectations for material properties, verification, and engineering assessment.
Section 1.9 was updated to align with current editions of NACE standards and reflects advancements in sour service material selection and performance. These changes are intended to:
- Incorporate higher-strength drill pipe grades now available in the industry
- Align material requirements with updated NACE guidance (e.g., TM0177 and MR0175/ISO 15156)
- Improve clarity around mechanical, chemical, and performance requirements and
- Support risk-based material selection and engineering evaluation for sour service applications.
- A detailed list of revisions is provided in Appendix A, Table 25: Edition 6.2 Revisions.
April 1, 2026
Developer: DACC
Sponsor Organization: CAPP
Current Status: Out for 90-day industry review. Closes June 30
Feedback: To provide feedback or comments regarding the IRP 1 Draft or any of the defined terms, please use the Feedback Form and send it to [email protected]
IRP 1 contains recommended practices for the design, selection, inspection, and management of drill string components used in the drilling of critical sour wells. The intent of this IRP is to support the prevention of loss of well control events in environments containing hydrogen sulphide (H2S), where equipment failure may result in significant safety, environmental, and public impact consequences.
This IRP addresses the material properties, inspection requirements, environmental cracking resistance, and operational considerations necessary to reduce the risk of equipment failure in sour service environments. Specific focus is placed on mitigating sulphide stress cracking (SSC), hydrogen-induced cracking (HIC), and other environmentally assisted cracking mechanisms that may affect drill string components exposed to H2S.