【History of Haichuan Pipelines】China’s independently laid longest domestic undersea pipeline

It is reported that once this gas field comes online, it will be able to provide long-term and stable energy supply to regions such as Guangdong, Hainan, and **. The South China Sea experiences frequent typhoons and large swells in winter, and the climate conditions are not suitable for offshore operations. The large-diameter submarine pipeline laid this time has a diameter of 80 centimeters, with each pipeline weighing 12 tons. The laying tension during normal installation reaches 160 tons, which is close to the upper limit for the normal operation of ships. Nevertheless, \"Offshore Oil 201\" managed to break the record for the laying speed of China’s 24-inch submarine pipeline \"S-LAY\" on four occasions, with the highest single-day laying distance reaching 4.02 kilometers.

It is worth mentioning that the \"Ocean Oil 201\", which was involved in the laying operations, is China’s first deep-water crane pipe-laying vessel. It can operate at depths of 3,000 meters and is capable of working in any part of the world except the Arctic; its overall operational capabilities place it at the forefront among similar engineering vessels internationally. The reporter learned that since its commissioning in 2012, the \"Ocean Oil 201\" has set the record for submarine pipeline laying in China 27 times. Among them, the daily pipe-laying speed reached as high as 6 kilometers, setting a record for the fastest pipe-laying speed in China’s offshore areas ； The maximum depth at which submarine pipelines were laid reached 1,409 meters, which is the deepest depth for pipeline laying in China and the second-deepest in the world for such \"S-LAY\" type pipelines. This achievement has helped raise China’s capability for independent pipeline laying to a leading level in Asia and among the advanced levels in the world, providing strong technical support for the development and utilization of marine oil and gas resources in China. (End)

It is worth mentioning that the \"Ocean Oil 201\", which was involved in the laying operations, is China’s first deep-water crane pipe-laying vessel. It can operate at depths of 3,000 meters and is capable of working in any part of the world except the Arctic; its overall operational capabilities place it at the forefront among similar engineering vessels internationally. The reporter learned that since its commissioning in 2012, the \"Ocean Oil 201\" has set the record for submarine pipeline laying in China 27 times. Among them, the daily pipe-laying speed reached as high as 6 kilometers, setting a record for the fastest pipe-laying speed in China’s offshore areas ； The maximum depth at which submarine pipelines were laid reached 1,409 meters, which is the deepest depth for pipeline laying in China and the second-deepest in the world for such \"S-LAY\" type pipelines. This achievement has helped raise China’s capability for independent pipeline laying to a leading level in Asia and among the advanced levels in the world, providing strong technical support for the development and utilization of marine oil and gas resources in China. (End)

The ship is designed as a double-deck deep-water pipe-laying vessel with self-propulsion capabilities, capable of operating at depths of up to 3000 meters. It is equipped with a dynamic positioning system, and a pipe-laying line is located along the longitudinal centerline of the main deck. A stern tube holder is present on the hull, along with seven fully rotatable propellers. Another important feature of this ship is its ability to carry out offshore engineering lifting operations; it is fitted with a heavy crane having a lifting capacity of 3500 tons (4000 tons when in a fixed stern configuration), which is mounted on cylindrical supports located along the longitudinal centerline of the hull. The interior layout is designed to accommodate 380 people, and a helicopter platform is available on the top deck, sufficient to accommodate the landing of Sikorsky S61N helicopters.

Main dimensions and parameters: Total length ~204.15 meters, Beam between perpendiculars 185.00 meters, Breadth 39.20 meters, Depth 14.00 meters, Draft 7.00 meters. Main generator: Diesel generator sets, 5440kW×6. Service speed: 12.0 knots

【History of Haichuan Pipes】The summary post is being updated continuously; learn about the development process of various pipes at https://bbs.hcbbs.com/thread-3068575-1-1.html (Source: Haichuan Chemical Industry Forum)

The significant development of the manufacturing sector has provided other industries with specialized construction machinery and equipment, turning what was once impossible into possible and resolving many difficulties

Regarding your comment, you can take a look at the related post: ‘==================== [History of Haichuan Pipelines] China’s first fully domestically produced natural gas project – the China-Russia East Route Natural Gas Pipeline https://bbs.hcbbs.com/thread-3075574-1-1.html (Source: Haichuan Chemical Forum)’

China’s Largest Offshore Self-operated Gas Field Shows Continued Productivity Reporters recently learned from relevant departments of CNOOC that A10H, an adjustment well at Dongfang 1-1 – China’s largest offshore self-operated gas field – has maintained a high level of natural gas production. Since it began operating in March this year, as of late July, this well has produced a total of 19 million cubic meters of gas. The Dongfang 1-1 gas field is showing new vitality, with a continuous supply of clean energy that will help Hainan advance the development of its free trade zone and free trade port. The high production of Well A10H is a reflection of CNOOC’s new round of basic geological and reservoir research, as well as its efforts to further optimize existing oil and gas fields in recent years. According to statistics, since the Dongfang 1-1 gas field was fully completed and put into operation in 2006, it has supplied over 30 billion cubic meters of gas to Hainan to date. However, as the development period lengthens, gas field production declines, making it difficult to meet the needs of downstream users; there is an urgent need to increase production by tapping into potential reserves. To this end, CNOOC has intensified its geological and reservoir research on gas fields in an effort to identify potential areas for further development. It is reported that alone in the Dongfang 1-1 gas field, 15 adjustment wells are planned to be drilled during the 13th Five-Year Plan period, which is expected to increase gas production by 6.9 billion cubic meters and reduce the rate of decline in the field’s output by 4 percentage points. Six adjustment wells have been completed, resulting in an increase of 2 million cubic meters of gas production per day. The Dongfang 1-1 gas field is located in the Yinggehai Basin of the Beibu Gulf in the South China Sea, about 110 kilometers away from Dongfang City. In 2003, the first phase of the Dongfang 1-1 gas field was put into operation. The natural gas produced there was mainly supplied to facilities such as the Fudao Phase II project, which was launched in the same year and represented China’s largest urea production facility at that time; this project is located in the Dongfang Industrial Park. In 2006, the second phase of the Dongfang 1-1 gas field was put into operation successfully, and the natural gas produced was primarily used to supply the 600,000-ton methanol project in our province.