New Super Martensitic - Ferritic Stainless Steel has been developed for HPHT applications.

January 5, 2012: Sumitomo Metals has developed a new Martensitic-Ferritic stainless steel OCTG, SM17CRS-125 (Super 17Cr) which features excellent corrosion resistance up to 200 degC, whereas under similar conditions Super 13Cr steels suffer both SCC and high corrosion rates.

Super Martensitic steel OCTGs have been widely used for CO2 containing well applications.  However, for HPHT (High Pressure High Temperature) applications in presence of CO2, where Super 13Cr material has temperature limitation in terms of SCC (Stress Corrosion Cracking) resistance,  duplex stainless steels have been generally selected.  Duplex stainless steels have better CO2 corrosion resistance at high temperatures but because of their richer chemical composition as well as the cold working process required to manufacture them they are more expensive vs. Super 13Cr materials.
To respond to the growing demand for superior corrosion resistant OCTG in HPHT applications, Sumitomo Metals has developed Super 17Cr as a Martensitic - Ferritic steel meant to feature better corrosion resistance than Super 13Cr but with a leaner chemistry versus duplex stainless steels allowing usage of more traditional H/T manufacturing process to achieve the material final properties.
Super 17Cr shows excellent corrosion resistance up to 200 degC, whereas under similar conditions Super 13Cr steels suffer both SCC and high corrosion rates. 
Super 17Cr has been already introduced by Sumitomo Metals in September 2011 at the ISO15156 OSC / NACE TG299 Meetingfor OCTG corrosion resistant materials and at the SPE “High Pressure/High Temperature Wells” ATW workshop held in Thailand.  The introduction of this new material has attracted the attention of major oil companies for its future potential usage in critical environments, and Sumitomo Metals has started providing material samples for “fit for purpose” customer qualifications.

 Taking into account the increasing worldwide energy demand, Sumitomo Metals will keep on contributing to the challenging oil and gas development, by providing a wide, unique and innovative high tech product line to meet industry demand.