Recently, the vessel “Jun Zheng Chengdu (SC CHENGDU)” successfully completed all repair works and departed slowly from the COSCO SHIPPING Heavy Industry (Shanghai) shipyard. After meticulous construction and rigorous inspections, the ship, entrusted with maritime missions, set sail again with a renewed appearance, heading back to the vast blue seas.
As the key focus of this repair project, the overhaul of critical ship components was managed with precision throughout the entire process by the project management team. For conventional outfitting components, the team implemented systematic replacement operations—from the installation accuracy of small connectors to the integrated testing of entire equipment sets—all strictly adhering to international maritime standards, ensuring seamless operation of all onboard systems. Simultaneously, the hull’s steel structure underwent “medical checkup-style” repairs, with ultrasonic flaw detection identifying potential defects and targeted reinforcement applied to worn areas, fortifying the vessel’s “steel skeleton” to fundamentally guarantee hull strength and sailing stability.
The specialized repair of the liquid cargo tanks was the “toughest battle” of this project. The “Jun Zheng Chengdu” features all-stainless-steel liquid cargo tanks, renowned for their superior corrosion resistance—a vital asset for ocean transport. However, after prolonged loading and unloading operations, minor cracks appeared locally on the tank walls. Left unaddressed, these “tiny flaws” could compromise cargo safety. Faced with this technical challenge, the project team demonstrated exceptional expertise: the hull supervisor led technical experts in analyzing ship documentation and comparing over a dozen material performance parameters, ultimately selecting 2205 duplex stainless steel (known as “super stainless steel” in the industry) as the repair material. This material combines high strength with corrosion resistance but demands “millimeter-level” precision in welding: temperature and current must be precisely controlled to prevent thermal cracking; welding rods require strict moisture and oxidation protection, along with special pre-use drying—any oversight could lead to repair failure.
Tasked with this mission, the hull workshop, embodying the state-owned enterprise’s commitment to “tackling challenges head-on,” deployed a specialized team with stainless-steel repair experience. Welders operated their torches with embroidery-like precision. After crack repairs, dye penetrant inspection was immediately applied, using developer reactions to scrutinize weld integrity, ensuring every repair met “zero-defect” standards. Finally, passivation treatment formed a dense protective film on the stainless-steel surface, boosting the tank walls’ corrosion resistance by 30% compared to pre-repair conditions—erecting a “long-term protective shield” for the liquid cargo tanks.
From “meticulous refinement” in routine maintenance to “breaking barriers” in technical challenges, the completion of “Jun Zheng Chengdu” represents not just a comprehensive upgrade in vessel performance but also a vivid demonstration of COSCO SHIPPING Heavy Industry (Shanghai)’s dedication to “craftsmanship.” The shipyard will continue leveraging technological innovation to enhance repair quality, empowering vessels to traverse vast oceans, driving high-quality enterprise development, and striving to build a flagship green, low-carbon, and intelligent ship and offshore engineering repair and conversion facility!
