Recently, located in the South China Sea, CNOOC Wenchang 19-1N and 8-3E oil field capacity release project seabed oil pipeline laying completed. This is the first laying of stainless steel composite double-layer submarine pipe in China, the operation is the most difficult in China, and the two new welding technologies are also applied for the first time.

The total length of the stainless steel composite double-layer sea pipe laid this time is 4.92 kilometers. The inner pipe is a 6-inch bimetal mechanical composite sea pipe with a 3mm stainless steel lining layer. The outer pipe is a 10-inch ordinary carbon steel pipe. The middle of the two sea pipes is filled with a 30mm thick insulation layer. Among them, the most important inner tube is manufactured by the aviation materials company under the Fourth Research Institute of Aerospace Science and Technology Group Corporation in Xi'an. At the same time, the company also provides an overall solution for on-site construction.

 
In this project, the aviation material company pioneered the narrow-cut, zero-gap butt welding process, and the total qualified rate of welding quality has been greatly improved, which not only proves that CNOOC has fully mastered the laying technology of composite submarine pipes, but also proves once again that the product quality and construction scheme provided by the aviation material company have reached the strict CNOOC standards.

In recent years, relying on the advantages of solid power technology, the Fourth Academy of Aerospace Science and Technology has vigorously developed dual-use products for military and civilian use. The bimetallic composite pipe produced by aerospace deflagration technology in China has significantly improved the corrosion resistance of the pipeline, extended the service life, and low cost. As early as 2011, the company broke the foreign monopoly in the international bidding of the large-scale subsea gathering and transportation pipeline project of China National Offshore Oil Corporation, and created the first time that CNOOC used domestic bimetal composite pipes in the subsea gathering and transportation pipeline system. A breakthrough in the application of bimetal composite pipes from land to marine applications.