It was learned on August 29 that the largest domestic subsea pipeline end terminal (PLET) independently designed and built by China had been successfully installed in Lingshui waters of Hainan Island.

The installed subsea PLET, which is an important part of 20-inch long-distance pipeline in the second phase of the Deep Sea No. 1 project, is used to connect pipelines and other subsea production facilities. 

The PLET is made of stainless steel lined composite material, with a pipe diameter of 508 mm, a wall thickness of 37.9 mm, and a weight of 79 tons. During installation of the PLET, the deviation of ship heading must not exceed 1.5 degrees and the horizontal deviation must not exceed 2.5 degrees.

For this installation, COOEC independently developed five new technologies, such as "integral side installation of subsea PLET" and “high-precision positioning system for underwater monitoring”, and only took less than 3 hours to complete the lowering of the subsea PLET, with installation accuracy satisfying the needs of technical standard.

The proved gas reserves in the second phase of the Deep Sea No.1 project reach 50 billion cubic meters. With the innovative oil and gas exploitation mode of "underwater production system + shallow water jacket platform + deepwater semi-submersible platform remote control system", the Deep Sea No.1 large gas field can witness an increase of its peak annual output from 3 billion cubic meters to 4.5 billion cubic meters after being put into operation.