Sou Hu Cai Jing·2026-01-07 12:25Group 1 - The State Intellectual Property Office of China shows that China National Petroleum Corporation (CNPC), China National Petroleum Group Marine Engineering Co., Ltd., and China National Petroleum Group Marine Engineering (Qingdao) Co., Ltd. have applied for a patent titled "Quality Control Method for Prefabrication and Welding of Skirt Piles Applicable to Deepwater Jacket Structures," published under CN121267444A, with an application date of December 2024 [1] - The patent pertains to the field of welding technology and introduces a method for quality control in the prefabrication and welding of skirt piles, which consist of more than N conduits, where N is greater than or equal to 2. The method includes steps such as building a prefabrication platform, layered splicing, and full splicing of conduits, aimed at reducing the number of components and assembly time while ensuring structural strength and improving installation and welding efficiency [1] Group 2 - CNPC was established in 1990 and is based in Beijing, primarily engaged in oil and gas extraction. The company has a registered capital of 48.69 billion RMB and has invested in 107 enterprises, participated in 5,000 bidding projects, and holds 1,447 trademark records and 5,000 patent records [2] - China National Petroleum Group Marine Engineering Co., Ltd. was founded in 2004, also located in Beijing, with a registered capital of 659.353 million RMB. The company has invested in 4 enterprises, participated in 1,983 bidding projects, and holds 16 trademark records and 521 patent records [2] - China National Petroleum Group Marine Engineering (Qingdao) Co., Ltd. was established in 2006 in Qingdao, focusing on general equipment manufacturing, with a registered capital of 500 million RMB. The company has participated in 580 bidding projects and holds 68 patent records [2]