In the elevator transmission system, the traction wheel serves as the core load-bearing component of the steel wire rope, and its groove accuracy, coaxiality, and surface roughness directly determine the smoothness and safety life of the elevator operation (the national standard requires the service life of the traction wheel to be no less than 10 years/2 million starts and stops). A leading domestic elevator manufacturer once faced a bottleneck in the processing of traction wheels: for the Φ 800-1200mm ductile iron (QT600-3) traction wheel, traditional processing requires three steps: "horizontal lathe roughing → vertical milling machine milling rope groove → grinding machine precision grinding", with a single piece processing cycle of up to 45 minutes; Due to multiple clamping, the coaxiality error between the inner hole and the rope groove often exceeds 0.1mm, resulting in a wire rope eccentric wear rate of 12%; At the same time, the machining accuracy of the rope groove surface is insufficient (tolerance exceeding 0.08mm), and the elevator is prone to low-frequency abnormal noise during operation. The after-sales complaint rate accounts for 35% of mechanical failures.
In the elevator transmission system, the traction wheel serves as the core load-bearing component of the steel wire rope, and its groove accuracy, coaxiality, and surface roughness directly determine the smoothness and safety life of the elevator operation (the national standard requires the service life of the traction wheel to be no less than 10 years/2 million starts and stops). A leading domestic elevator manufacturer once faced a bottleneck in the processing of traction wheels: for the Φ 800-1200mm ductile iron (QT600-3) traction wheel, traditional processing requires three steps: "horizontal lathe roughing → vertical milling machine milling rope groove → grinding machine precision grinding", with a single piece processing cycle of up to 45 minutes; Due to multiple clamping, the coaxiality error between the inner hole and the rope groove often exceeds 0.1mm, resulting in a wire rope eccentric wear rate of 12%; At the same time, the machining accuracy of the rope groove surface is insufficient (tolerance exceeding 0.08mm), and the elevator is prone to low-frequency abnormal noise during operation. The after-sales complaint rate accounts for 35% of mechanical failures.
special fixture
In terms of technological innovation, the equipment has achieved a breakthrough in the "process integration" of traction wheel processing: integrating a 21 inch large-diameter chuck (with a clamping force of 80kN), an 8-station electric tool tower (with a tool change time of 1.8 seconds), and a specialized formed tool holder for rope grooves. It can complete the processing of traction wheel inner holes (tolerance H7), outer circles (tolerance IT6), end faces, and 6-8 rope grooves (groove shapes are U/V, groove depth tolerance ± 0.02mm) in one go. In response to the difficulty of forming the curved surface of the rope groove, the "segmented CNC interpolation" process is adopted. By collecting surface data at 1000 points per circle, the straightness of the rope groove busbar is stably controlled at 0.015mm/m; In response to the differences in traction wheel specifications for elevators with different loads (1000kg-3000kg), the equipment is equipped with 20 sets of process parameter templates, reducing the changeover time from traditional 2.5 hours to 20 minutes.
The implementation results are significantly in line with the strict standards of the elevator industry: the single piece processing cycle has been compressed from 45 minutes to 28 minutes, and the daily production capacity has been increased from 120 sets to 210 sets; The coaxiality between the inner hole of the traction wheel and the rope groove is stably controlled at ≤ 0.05mm, the rope groove tolerance is ≤ 0.03mm, and the surface roughness reaches Ra0.6 μ m, fully meeting the requirements of GB/T 13435-2008 "Elevator Traction Machine" standard; The wire rope eccentric wear rate has decreased from 12% to 1.5%, the elevator operation abnormal noise complaint rate has decreased by 90%, and the after-sales maintenance cost has been reduced by 40%. The intelligent monitoring module equipped on the equipment can collect key data such as spindle load (accuracy ± 1%) and cutting temperature (resolution 0.1 ℃) in real time. Combined with tool wear prediction algorithms, the tool life is extended by 35%, the comprehensive utilization rate of the equipment is increased from 78% to 92%, and the annual downtime is reduced by 420 hours.
VTC60 has enabled us to achieve a dual guarantee of 'precision and safety' for the traction wheel. ”The production director of the company stated, 'Our traction wheels have not only passed the rigorous certification of EU EN 81-1:2020, but also meet the ultimate requirements for transmission stability of super high-rise elevators (over 100 floors), laying a core foundation for us to explore high-end overseas markets.'. ”This case confirms that the CNC vertical lathe has become a key equipment for breaking through the "safety accuracy bottleneck" in the field of elevator traction wheel manufacturing through the deep collaboration of "rigid structure+precise shape control+process integration".
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