MSE Colloquium: Douglas P. Fairchild, Local Hard Zones in Sour Service Pipe Steels

Abstract

Many oil and gas resources contain the byproduct of hydrogen sulfide (H2S).  The materials used to construct sour service facilities, and in particular the pipelines, must be resilient against degradation mechanisms like sulfide stress cracking (SSC) and hydrogen induced cracking (HIC).  In 2013, the Kashagan project in the North Caspian region of Kazakhstan experienced the failure of its main pipelines.  These pipelines were brand new and fabricated from thermomechanical control process (TMCP) steel.  TMCP technology is arguably the steel industry’s most significant development in the last half century and the failure of the Kashagan pipelines has motivated re-evaluation of the technology.  The failure mechanism was identified as SSC that initiated in hard spots (zones) in the steel.  The remediation has been estimated to cost ~$3.6G.

TMCP plate steel used for sour service pipe utilizes a combination of key microalloy elements (Nb, Ti), intensified rolling within particular temperature regimes, and a final step of accelerated cooling using a massive volume of high pressure cooling water delivered through thousands of spray nozzles.  Only a few mills worldwide are capable of applying this technology.  Investigations by ExxonMobil indicate that upsets in the accelerated cooling process can cause cooling rates that are an order of magnitude higher than intended.  Such upsets are believed to be rare, but possible using commercial TMCP equipment.  This presentation will explain TMCP technology and what is believed to be the root cause of Kashagan local hard zones.

Bio

Doug holds BS, MS and PhD degrees in Welding Engineering from OSU and he joined Exxon in 1982.  He has worked primarily in R&D focusing on the areas of welding engineering, physical metallurgy, fracture mechanics, and failure analysis.  Doug has conducted extensive work in the area of high strength steels.  His work has applications to the design and fabrication of structures used for the exploration and production of oil and gas.  These structures include pipelines, offshore structures, ships, pressure vessels, and liquefied natural gas facilities.  His work on, and the naming of, local brittle zones provided the basis for the industry standard API RP2Z.  Doug’s work also includes the welding technology that was used to construct the world’s strongest pipeline, X120, in 2004.  Doug was a 2018 recipient of a Distinguished Alumni award from OSU’s College of Engineering and is the 2019 recipient of the annual Jin Chung award for career achievement from the Int’l Society of Offshore and Polar Engineers.  Doug has produced about 75 publications and 12 patents.