To systematically enhance the quality of core shipbuilding processes, Jiangsu Haizhouzhong Shipping Industry Co., Ltd. officially established the "Welding Quality Special Improvement Team" at the end of 2025. The team is led by the company's Quality Department and brings together technical experts from the block assembly and section workshops under the Production Department. Additionally, it includes on-site surveyors from the China Classification Society (CCS) as technical advisors, forming a collaborative "internal execution + external supervision" operational mechanism.
The team’s primary task is to standardize the processes for high-frequency welds in production. In the initial phase, the team focused on six common weld types, including fillet welds, vertical butt welds, and horizontal welds. Based on the latest national standards and classification society requirements, a comprehensive review and detailed revision of the existing process specifications were conducted. Key revisions included clarifying welding parameter ranges for different plate thickness combinations, standardizing pre-weld cleaning and preheating requirements, and unifying inspection criteria for weld appearance and internal quality. Based on these revisions, the team compiled illustrated versions of the New Edition Welding Operation Instruction Manual and the Typical Defect Identification and Repair Guide.
The new process documents were first piloted in the hull section workshop and some outfitting manufacturing areas. During the pilot phase, the team implemented a "process card" system, where welders worked daily using cards that clearly specified the weld joint type, applicable parameters, and key control points for their shift. Meanwhile, the frequency of quality inspections was increased, and rapid weld dimension measurement tools were introduced, enabling real-time recording and analysis of process data.
After nearly three months of pilot operation, the effectiveness of the specialized management was reflected in key data: the first-pass qualification rate for welding in the two pilot areas during classification society inspections steadily increased from an average of 92% before implementation to 95%. More importantly, rework hours caused by welding defects decreased by approximately 15%, not only improving production efficiency but also reducing secondary consumption of materials and energy.
"Quality improvement is by no means an overnight achievement; it is a process that requires continuous investment and meticulous management," said Business Director Lu Feng. "The pilot results validate the effectiveness of process standardization and stringent process control. However, we are well aware that stable quality ultimately depends on the skills and sense of responsibility of every welder."
Based on this, the next phase of the team’s work will focus on empowering "people." Starting next quarter, targeted training will be provided to 35 selected intermediate-level welders. The training will combine theoretical instruction and hands-on practice, emphasizing the understanding and implementation of new process standards, as well as defect prevention awareness. The company plans to gradually extend the mature process standards and quality management model, validated during the pilot, to all workshops and workstations involved in welding operations within the plant by the end of the year.
Deputy General Manager Deng Cihuo emphasized in conclusion, "Our goals are pragmatic. We hope that through this systematic approach, within the next two years, the average first-pass qualification rate for welding in the company’s ship products will be stably maintained above 96%, thereby laying the most solid foundation for the long-term structural safety and reliability of the ships." The continued advancement of this work also reflects Haizhouzhong Shipbuilding’s firm commitment to strengthening fundamental manufacturing capabilities and pursuing endogenous quality growth.