Drill Pipe Grades Improvements and Industry Standards Evolutions to Address Increasing H2S Challenges: a Decade in Review

Abstract

Abstract Hydrogen Sulfide (H2S) can interact with steel tubular, and through the unfavorable combination of different factors can initiate a crack in the material, which could propagate until failure. This phenomenon can occur when stresses are largely below the material yield strength. The combination of tubular failures due to Sulfide Stress Cracking (SSC) and the rising HSE concerns when dealing with sour gas has led the industry to develop new drill pipe grades with enhanced resistance to SSC. Material selection for drill pipe in a sour environment is significantly unclear, mainly due to the absence of existing international standard specifically related to H2S resistant drill pipe. Nonetheless, Canada has led the way by publishing their "Industry Recommended Practices" (IRP) Volume 1 in 2004; the standard was created to insist on people safety, and provide specification and guidelines to manufacturers on material properties, quality control, testing and inspection of drilling products intended to be used in critical sour wells. Sour Service Drill Pipe as defined in the IRP has been used for over a decade in Canada, as well as in other parts of the world. Manufacturers have also developed a variety of other proprietary Sour Service grades of drill pipe and BHA. This paper proposes a review of different field cases in the Middle East and Asia, as well as an outlook of the different practices for material selection and qualification guidelines which have emerged since the past 10 years. With the current increasing demand of domestic gas in different part of the world, some highly sour oil and gas reservoirs are being explored with H2S contents beyond what could have been imagined a decade ago. To explore, appraise and eventually develop such fields, most of the time combined with complex well profiles or deeper reservoirs, significant technical challenges need to be addressed regarding drill pipe integrity and operations safety. This paper proposes a non-exhaustive review of the newest emerging industry trends as far as international standard guidance, regional normative initiatives, and new steel developments.