Yangzhou Dilong YD3500 Slewing Bearing Rock Pipe Jacking Machine has been successfully applied to the Power Transmission Line Relocation Project at Zengcheng South Station in Guangzhou and completed the full-length jacking works. Leveraging the structural merits of its dedicated slewing bearing and powerful hard rock tunnelling performance, the machine successfully overcomes challenges of long-distance excavation in ultra-high-strength rock strata. It maintained stable and efficient operation throughout construction with outstanding tunnel forming quality, demonstrating the top-tier construction capacity of our large rock pipe jacking equipment under high-strength rock conditions.
The Power Transmission Line Relocation Project at Zengcheng South Station, Guangzhou, is a vital supporting power infrastructure project in the region. It plays a key role in optimising the layout of regional power transmission lines, ensuring safe power delivery and improving the urban power infrastructure system. The tunnelling section consists of intact, dense and hard full-face rock strata with rock compressive strength reaching up to 130 MPa, representing an extremely challenging ultra-hard rock jacking condition within the industry. Tunnelling in ultra-hard rock generates heavy excavation resistance and poses great rock-breaking difficulties. Common challenges include severe cutterhead wear, tunnelling stagnation, delayed progress and attitude deviation. Therefore, stringent requirements are imposed on the equipment’s rock-breaking capacity, structural strength, wear resistance and stability during long-distance continuous tunnelling.
To address the construction difficulties of long-distance tunnelling in full-face 130 MPa ultra-hard rock strata, our YD3500 Slewing Bearing Rock Pipe Jacking Machine brings its exclusive core advantages into full play. Equipped with a high-quality slewing bearing structure, the machine features high load capacity, stable operation and superior wear resistance, perfectly adapting to continuous impact tunnelling in ultra-hard rock. Optimised specifically for hard rock applications, it is fitted with a high-strength dedicated rock-breaking cutterhead and delivers robust power output to efficiently crush rock with compressive strength up to 130 MPa. The equipment effectively avoids various mechanical risks and construction obstacles in hard rock tunnelling, precisely controls tunnelling attitude and tunnel alignment, and fully complies with rigorous technical standards for long-distance jacking in ultra-hard rock.
During the whole construction process, the YD3500 Slewing Bearing Rock Pipe Jacking Machine exhibited remarkable stratum adaptability. The unit operated smoothly with sustained and ample tunnelling power, coping effectively with heavy resistance from ultra-hard rock strata and steadily advancing long-distance jacking operations. All working parameters and tunnelling attitude remained controllable, and the tunnel cross-section was well formed without stagnation, deviation or safety hazards. The machine accomplished the full-face ultra-hard rock tunnelling task to high standards, fully highlighting the unique technical advantages of slewing bearing type rock pipe jacking machines under ultra-high-strength rock conditions.
The successful completion of the power relocation project in Zengcheng, Guangzhou, fully verifies the outstanding performance and reliable stability of the YD3500 Slewing Bearing Rock Pipe Jacking Machine for long-distance tunnelling in full-face rock strata with strength up to 130 MPa, and underscores the equipment’s distinctive structural advantages and powerful tunnelling capacity. Valuable practical experience has been accumulated for domestic long-distance pipe jacking projects of power pipelines in ultra-hard rock strata. It further enriches application cases of large rock pipe jacking machines under complex geological conditions and continuously promotes the high-quality upgrading of urban power infrastructure.