OREANDA-NEWS. February 21, 2012. In the deep South China Sea there will soon be a steel "dragon", more than 170 kilometers of which is built of Baosteel steel pipes, reported the press-centre of Baosteel.

With the support of the relevant Baosteel Co.,Ltd. departments, recently, Tube, Pipe and Bar Business Unit successfully completes two contracts for the South China Sea Liwan 3-1 gas field: 4500-ton deep-sea seamless submarine linepipe and 43000-ton deep-water natural gas transmission UOE linepipe.

The South China Sea Liwan 3-1 gas field is China's first deep-sea (1500 m below water) gas field, as well as China's largest and deepest offshore gas field and it has very important strategic significance.

At the end of 2009, led by Tube,Pipe and Bar Business Unit, the team composed of relevant Baosteel Co.,Ltd. departments won the bid for Liwan 3-1 gas field seamless X65 submarine linepipe in competition with domestic and foreign steel companies and got  the first contract of seamless deep-sea seamless submarine linepipe in China. This project is Baosteel's first trial in mass production of X65 grade seamless line pipe in accordance with the norms of international DNV sea tube, with a total of seven specifications and 4500 tons. The contract requires high dimensional accuracy, complex process, narrow range of after heat-treatment performance requirements, high testing requirements and high hydrostatic test pressure. It also requires one-by-one tracking. It is the contract with greatest production difficulty since Tube, Pipe and Bar Business Unit's seamless steel pipe plant was built.

During the manufacturing process, with the support of Baosteel relevant departments, Tube, Pipe and Bar Business Unit adheres to refined work ethic, strictly follows Liwan sea pipe technical memos and post procedure standards, does technology research, optimizes production processes, strengthens internal process collaboration and product process tracking, be strict with product quality, strengthen coordination with the foreign supervision. After hard work, it successfully completes all contract production tasks. As a result, Tube,Pipe and Bar Business Unit forms DNV undersea linepipe production process and rolling technology specification and further enhances Baosteel excellent seamless steel pipe manufacturing capacity.

In November 2010, under the concerted efforts of Baosteel high-grade line pipe production, marketing and research team, Tube, Pipe and Bar Business Unit successfully obtained South China Sea Liwan 3-1 gas field 43,000-ton deep-water natural gas transmission line pipe contract. This project has very high steel pipe stability and security requirements and is of  manufacturing difficulty.

Led by Tube, Pipe and Bar Business Unit, the project team members from Baosteel Co.,Ltd. Manufacturing Department, Steel Mill, Heavy Plate Department, Baosteel Research Institute, Baosteel Technical Inspection and Analysis Center works together to formulate strict production plan, and organizes production in strict accordance with the user standards.Throughout the production process, Baosteel makes use of whole process technical management advantages from smelting to UOE pipe, overcomes technical problems in steelmaking, rolling and pipemaking. Tube, Pipe and Bar Business Unit's UOE production plant does 12 technological research such as edge-milling process optimization and take various measures to enhance the weld drying capacity and nondestructive testing capability. With the efforts of the project team, product quality is stable and mass production finished product rate achieves a good level. According to testing, the technical performance indicators all meet customer requirements and fully meet the requirements of the DNV standards.

The successful completion of the contract marks that Baosteel has the capacity to  produce UOE thick-walled sea premium welded pipe and fills China's blank in large-diameter thick-walled sea pipe and provides strong support for CNOOC to develop deep-sea oil and gas fields and improve localization.