Development of Coated Tubing for Oil/Gas Production in Sour Environment

To develop inside coated tubing for sour environments, a joint research program has been conducted by japan Research and Development Center for metals (JRCM) and Japan National Oil Corporation (JNOC). The aim of this project is to develop a cheap oil country tubular goods (OCTG) with high corrosion resistance in sour environment using new coating technology on carbon steel. Coating facilities by plasma transferred arc hard facing (PTH) process that was applied for tubing, was constructed. Developed coated tubing (5 m long x 89 mm O.D. x 76 mm I.D) and connection was manufactured and tested corrosion resistance and joint performance. Antigalling property and gas tightness is equivalent to conventional joint coated tubing and connection evaluated corrosion resistance in dynamic corrosion tester and field test. No corrosion damage was observed after tests. These results suggest that developed tubing and connection can be used in deep sour wells.