【Ten Years of Rapid Development in Chemical Engineering Equipment】From 2031 to 2026, CNOOC Engineering has mastered welding technology for ultra-high-strength steel at 865 MPa

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Let’s give praise and encouragement to the achievements made in China’s chemical engineering technology and equipment; your participation in discussions is the greatest encouragement. **********************【Ten Years of Great Progress in Chemical Engineering Equipment】Regular updates and summaries are available – feel free to join the discussions: https://bbs.hcbbs.com/thread-3576046-1-1.html *****************On April 26th, it was reported by Offshore Oil Engineering Co., Ltd. that significant progress has been made in the welding technology for 865 MPa-grade ultra-high strength steel, a technology developed independently by Offshore Oil Engineering’s Qingdao branch. This technology was successfully applied in the welding of support structures for the 6S project in Qatar, where 100% ultrasonic and magnetic particle testing was carried out successfully, with all parameters meeting the required standards. This development fills a gap in China’s capabilities in welding ultra-high strength steel, providing essential technical support for the exploration of deep-sea oil and gas resources as well as for the construction of major projects in deep waters. As marine equipment moves into deeper waters, ultra-high strength steel is being used more and more frequently due to its advantages of being \"stronger, lighter, and safer.\" However, for a long time, the welding of ultra-high-strength steel has faced various challenges such as difficulty in welding, tendency to crack, and sensitivity to deformation. Welding ultra-high-strength steel with strengths above 800 MPa is considered a significant technical challenge on a global scale, and only a few developed countries have previously mastered this technique. Faced with this challenge, CNOOC Engineering Qingdao Company developed an innovative collaborative problem-solving model that combines senior engineers and skill masters. The welding technology team devised specialized process solutions to address the key issue of the high sensitivity of 865 MPa-grade steel to cold cracking. The team of skill masters, relying on their practical experience, ensured precise control over weld quality, creating a seamless loop from process design to actual implementation on site. This process is akin to performing a precise \"minimally invasive surgery\" on the steel material: by carrying out welding within a precisely controlled temperature range, it maximizes the preservation of the material’s original mechanical properties, ensures that the strength of the weld matches that of the material, and reduces welding residual stresses as well as the likelihood of cracks through measures such as controlled cooling. In this way, the long-standing problem of brittle fracture during welding of ultra-high-strength steel was successfully overcome. This successful breakthrough in technology signifies that the company has joined the international forefront in the field of welding ultra-high-strength steels at pressures above 800 megapascals, further enhancing China’s competitiveness in the international high-end offshore engineering market.