On the morning of June 26, the world’s largest ordinary self-propelled 73,000 DWT deck carrier (NY035) commenced construction smoothly at China Railway Baoji Bridge (Yangzhou) Co., Ltd. The launch of this project marks that China Railway Baoji Bridge Group has successfully broken through its inherent traditional business boundaries, achieving a significant breakthrough from “bridge building on land” to “shipbuilding at sea.”
Representatives from Zhongyuan Shipping, Jingjiang Nanyang Shipbuilding Co., Ltd., China Classification Society, FLEET MANAGEMENT LIMITED, Shanghai Weifang Ship Technology Co., Ltd., Jiangsu Dagen Offshore Engineering Service Co., Ltd., and the project management team of China Railway Baoji Bridge Group gathered at the site to jointly witness the important moment of the project’s commencement.
All participating representatives unanimously stated that they will maintain efficient coordination and collaborative攻坚 throughout the entire process. China Railway Baoji Bridge Group will strictly control construction standards, coordinate resource allocation, and strictly manage block construction quality; Jingjiang Nanyang will refine the construction schedule, closely monitor milestones, and execute precision construction; China Classification Society will provide full follow-up, offering professional technical support and quality supervision; Zhongyuan Shipping will ensure overall coordination and connection, with all parties strictly controlling quality and steadily advancing construction to fully guarantee the high-quality and on-time delivery of the vessel.
The 73,000 DWT ordinary self-propelled deck carrier that commenced construction this time is the world’s largest vessel of its type, with leading hardware parameters in the industry: total length of 256 meters, molded breadth of 62 meters, molded depth of 13.5 meters, design draft of 8.6 meters, in-port operating draft of 11.4 meters, and a deadweight capacity of 73,000 tons.
China Railway Baoji Bridge Yangzhou Company is primarily responsible for the manufacturing of the cargo hold section hull blocks. The entire cargo hold area is divided into 11 ring sections, each ring section is divided into 10 blocks, totaling 110 blocks. The maximum single block size is approximately 13 meters x 13 meters x 7 meters, with a maximum single weight of about 190 tons.
Facing challenges, the project team of China Railway Baoji Bridge Group implemented precise measures and tackled problems one by one: To address issues of no-margin manufacturing for oversized blocks, susceptibility to welding deformation, and excessive butt-joint tolerances, a set of processes including CNC precision cutting with reserved shrinkage allowance, rigid jig unified datum, symmetrical light welding plus temporary support reinforcement, and total station re-measurement and rectification were adopted to precisely control construction errors and ensure assembly accuracy.
To tackle the difficulties of complex hull coating systems, multiple overlapping construction processes, and stringent quality control requirements, a customized zoning coating special plan was formulated. Strict control over construction temperature and humidity, and rust removal grades was implemented, edge pre-coating operations were strengthened, and film thickness and adhesion were inspected section by section, achieving one-time compliance for anti-corrosion and tightness acceptance.
At the same time, the project also applied a number of advanced manufacturing processes to create a benchmark for efficient construction. The project team optimized the thin plate back-gouging-free submerged arc splicing process, eliminating the traditional back-gouging procedure, achieving one-time forming, and reducing welding defects and base material damage. Collaborative welding robots were deployed, adapting to the complex conditions of the cabins to ensure standardized weld quality. The direct welding process on weldable primer was applied, allowing welding without extensive grinding, balancing anti-corrosion performance and construction efficiency. The combined application of this series of advanced processes significantly improved the project’s construction quality, efficiency, and standardization level.
As the core construction unit for this project, China Railway Baoji Bridge Group Yangzhou Company, relying on the complete hardware facilities and mature intelligent manufacturing system of its 5G smart factory, provides full support for the high-quality advancement of the project, comprehensively demonstrating its strong capabilities in marine engineering construction. The company is equipped with 4kW CNC laser cutting equipment, achieving high-precision intelligent blanking. The fully self-developed electric beam transport vehicles enable unmanned transportation of workpieces, replacing imported fuel equipment, offering advantages of green energy saving and convenient operation and maintenance, suitable for various workpiece transfer needs. The professional heavy steel structure plant is equipped with large heavy-duty crane equipment, possessing strong lifting and carrying capacity, capable of efficiently completing the hoisting and transfer of large and heavy workpieces, meeting the production needs of large-scale precision machining.
Meanwhile, the factory dock has 4 specialized berths, of which No. 1 is a 3,000-ton general cargo berth with an annual throughput capacity of 280,000 tons; Berths 2-4 include three 5,000-ton general cargo berths with a total length of 390 meters and a maximum annual throughput capacity of 458,000 tons, providing complete logistics support for ship construction, workpiece transfer, and finished product delivery.
The commencement of this project is a key breakthrough for China Railway Baoji Bridge Group’s strategic upgrade from “land-based steel structures” to “marine heavy steel structures.” In the future, China Railway Baoji Bridge Group will continue to deeply cultivate the marine engineering field, optimize production processes, tackle core technologies, empower industrial upgrading with new quality productive forces, strive to create benchmark quality projects, and cultivate a second growth curve for enterprise development.
It is understood that China Railway Baoji Bridge Group Co., Ltd., a subsidiary of China Railway Group Limited, is a large state-owned enterprise specializing in the manufacturing of steel bridges, steel structures, railway turnouts, urban rail transit equipment, and large lifting machinery. Its subsidiary, China Railway Baoji Bridge (Yangzhou) Co., Ltd., is located in the Guangling District Industrial Park, Yangzhou City, covering an area of 689 mu. It houses a 63,500 square meter large riveting and welding combined plant and machining plant, a 3,000 square meter painting plant, a 6,900 square meter sandblasting plant, a 3,000-ton material intake dock, a 5,000-ton basin dock, as well as over 400 units of various transportation equipment and large machinery, with an annual production capacity of 150,000 tons of steel girders and steel structures.
