Congratulations to the "Zhenxing" tunnel boring machine on the successful completion of its cutter inspection!
2020-07-03
The "Zhenxing" tunnel boring machine used for the right line of the Yanlu Passage over-river project is a 15-meter-class, ultra-large-diameter slurry shield designed and manufactured by CCCC Tianhe specifically for Nanjing's cross-river tunnel. The tunnel’s shield-driven section spans a total length of 2,975 meters. This project features significant characteristics such as a large cross-section, high water pressure, extended distances, and exceptionally abrasive ground conditions. Moreover, most of the construction lies beneath the riverbed, with the hardest rock layers in the hard-rock sections exceeding 70 MPa in strength. The diverse and complex geological conditions place extremely stringent demands on the cutting tools used during excavation.
Used for the right line of the Yanlu Passage across the river ” Revitalization Ship ” The tunnel boring machine was designed and manufactured by CCCC Tianhe specifically for Nanjing's cross-river tunnel. A 15-meter-class, ultra-large-diameter slurry shield tunneling machine—tunnel shield section with full length 2975 Mr., this project features characteristics such as a large cross-section, high water pressure, long distances, and high abrasiveness—and most of the construction sections lie beneath riverbeds, with the maximum rock strength in the hard-rock zones exceeding 70MPa , geological diversity and complexity place extremely high demands on cutting tools.
Our company has addressed the tooling requirements and project geological characteristics raised by the host manufacturer, while leveraging our expertise gained from the heavy-duty tearing cutter used in the Nanjing Weisan Road project. Over 2,500-meter successful cases without tool changes demonstrate thorough research into similar tool application scenarios, careful selection of appropriate cemented carbide parameters and welding techniques, the use of wear-resistant and more versatile materials with superior performance, optimized adjustments to the positioning of wear-resistant coatings and the precise ratio of cemented carbide to other components, and the design and development of initial cutting tools tailored to meet the specific requirements of equipment manufacturers.
The right-line tunnel boring machine for the Yanlu Passage crossing the river was 2019 12 Month 25 Departure at dawn, deadline by sunset 2020 Year 6 The first monthly tool inspection has been completed. 820 Rice, primarily for cross-border travel 20 Rice, solid form, and 800 Rice flour and fine sand layer. During this warehouse opening project, the project team inspected the normally pressurized, replaceable cutters installed along different trajectories on the cutterhead, randomly selecting those representing the most challenging and unfavorable working conditions. 6 The cutting tools were inspected, and their wear levels were all within the acceptable range. 5mm Right, the minimum wear amount is just 2mm The cutting tools showed no signs of uneven wear or chipping. Combined with the analysis of parameters during the TBM’s propulsion process, it was determined that the initially installed cutting tools remain intact and exhibit minimal wear. Based on this assessment, the initially fitted replaceable cutting tools are expected to last throughout the entire tunnel segment. 1600 Dominant soft soil and soft sand strata.
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