On May 11th, China's first domestically produced deep-sea oil and gas production tree was installed in the sea area of Yinggehai, Hainan. The equipment is an important part of the underwater oil and gas production system engineering demonstration project led by CNOOC, marking a crucial step in the research and development of key technical equipment for China's deep-sea oil and gas development. The engineering demonstration and application project of the 500 meter underwater oil and gas production system implemented by CNOOC this time marks that China has the ability to design, construct, and apply complete sets of equipment.

The underwater production system is a key equipment for developing deep water oil and gas fields, including underwater wellhead, underwater Christmas tree, underwater control system, underwater manifold, and other equipment. For a long time, only 5 European and American companies worldwide have mastered integrated manufacturing technology for underwater production systems, resulting in long procurement cycles, high prices, and difficult maintenance of this equipment. In 2018, CNOOC took the initiative and boldly proposed the need to use self-developed 500 meter underwater equipment to develop deepwater oil and gas, accelerating the breakthrough of key deepwater core technologies.

The water pressure at a depth of 500 meters is equivalent to about 50 times the atmospheric pressure. In the face of complex environments such as low temperatures and complex landforms on the seabed, as well as the harsh conditions of 20 years of maintenance free, the sealing strength of underwater equipment, the pressure bearing capacity of materials, and the quality of processes face severe technical challenges. There is no chance of trial and error, and any negligence may cause irreparable huge losses.

Even so, Mi Lijun, the president of CNOOC Research Institute, who is responsible for the development and design of the engineering demonstration application project for the 500 meter underwater oil and gas production system, believes that the underwater production system is an important link in China's journey towards the deep sea, and has accumulated more than ten years of underwater design experience. It is the duty of CNOOC to develop deep water oil and gas in the South China Sea with independent technology.

To achieve the autonomy of underwater equipment, it is necessary to first achieve the autonomy of underwater design technology. However, it is not easy to independently carry out the design of underwater production systems. Firstly, the domestic underwater technology team is in the early stages, and there are only a few talents with experience in deepwater engineering; Secondly, the maturity of underwater equipment technology in China is generally low, and a complete underwater production system equipment industry chain has not yet been formed; The third is the lack of a systematic technical system. In order to control the reliability of independently designed underwater production systems from the source, CNOOC Research Institute has comprehensively explored and fully identified the risks of underwater production system solutions at the design source. However, the commonly used analysis solution internationally is based on mature components for underwater production systems, and the underwater equipment developed in this project generally uses domestic components. How to control the application risk of the first set of products depends on limited conventional technical means.

To ensure the smooth implementation and operation of this demonstration project, the research team has fully digested and absorbed international underwater product standards and technical management, and developed a technology maturity evaluation system based on self-developed underwater production systems according to local conditions. The hundreds of key components of each equipment have been analyzed item by item in a "puzzle like" manner, and only after passing the final evaluation can they be applied to ensure the high reliability of the product, Control the implementation risks of the first set of products from the source.