After "cloud acceptance" and on-site acceptance, on July 1st, China Railway R303, a super-large diameter EPB shield machine developed by China Railway Industry, a subsidiary of China Railway, rolled off the production line in Tianjin, and will be applied to the Fortezza railway tunnel project in Italy, which is also the first remanufactured shield machine exported to Europe by China.
Remanufacturing of shield machine means to upgrade the original shield machine in an all-round way. In view of the engineering environment in which the shield machine will be applied, the application of geology, machine condition evaluation and key parts replacement are considered comprehensively, and the performance is upgraded from generation to generation, making it better than the original machine and reaching the performance of the latest generation tunnel boring machine. The data show that remanufactured products can save energy by 60%, material by 70% and cost by 50% on the basis of the quality and performance of new products.
"China Railway R303" shield machine was originally an extra-large diameter EPB shield machine exported by China Railway Industry to Dubai, United Arab Emirates, and was later repurchased. The excavation diameter of the reconstructed shield machine is 11.05 meters. According to the characteristics of high rock strength in the stratum of Fortezza Railway Tunnel Project and the needs of customers, China Railway Industry remanufactured the shield machine, and strengthened the structure of the cutter head panel by optimizing the hob trajectory, which made the original cutter head have stronger rock breaking ability and improved the tunneling efficiency.
China Railway Industry actively promoted technological innovation and technological innovation, vigorously carried out the remanufacturing business of shield machines, trained a large number of shield machine remanufacturing talents, and served a large number of key projects under construction. More than 100 remanufactured shield machines, such as the first remanufactured dual-mode and triple-mode shield machines in China, have been produced successively, and the remanufacturing tasks of various types of shield machines, such as new cutter head system and system transformation, have been completed. In 2017, the upgrading of the shield machine "China Railway No.1" was completed, and this "light of domestic products" bearing honor and history was reborn; In 2017, "China Railway No.209/No.210" completed the construction of the Tangshan Line of Singapore Metro. In 2018, China Railway Industry repurchased and remanufactured it and applied it to the construction of Fuzhou Metro.
At the same time, China Railway Industry is committed to the full-life cycle development of shield machines, and established Tianjin Company to build the largest shield machine manufacturing and remanufacturing base in northern China, as well as related parts storage centers and trading centers. Actively carry out research and development of main process characteristics and key technologies, and concentrate on overcoming key technologies such as maintenance and debugging of laser cladding pump/valve, maintenance and debugging of main drive and sealing system. At present, the shield machine testing center of Tianjin Company has been accredited by China Conformity Assessment and CNAS Laboratory, and has the technical ability to carry out testing services in accordance with relevant domestic and international accreditation standards, so that testing and maintenance can serve the whole process of shield remanufacturing production.
Up to now, China Railway Equipment, a subsidiary of China Railway Industry, has carried out 12 scientific research projects on shield remanufacturing, obtained a number of authorized patents, successfully selected into the fifth batch of green factories of the Ministry of Industry and Information Technology, and won the title of "Green Design Demonstration Enterprise for Industrial Products".
[Editor: Wen Cun]