超深矿井提升机制动盘热性能分析与优化

超深矿井提升机制动盘在紧急制动过程中由于受到摩擦循环热载荷的作用,内部产生较大的热应力,同时高温会导致制动盘和闸片摩擦制动性能下降甚至失效。针对制动盘制动热性能问题,根据热传导理论和有限元分析方法,建立了制动盘组件三维有限元模型,采取直接耦合方法对制动盘制动过程中的热应力场进行模拟研究,并通过实验验证了仿真参数设置的正确性。分析了闸片数量和排布方式对制动工况下制动盘温度和应力分布的影响。结果表明,在制动阶段,制动盘摩擦面温度先急剧上升,后缓慢下降,摩擦面温度呈现锯齿状波动性变化,制动过程中应力变化规律与温度变化规律相同。原制动盘在制动过程中的最高温度为134.8℃,最大应力为230.2MPa,高温和大应力区域集中于摩擦面附近;增加闸片数量的制动盘最高温度为142.4℃,最大应力为251.1 MPa,高温和大应力区域同样集中于摩擦面附近;改变闸片排布方式的制动盘最高温度为86.5℃,最大应力为119.1MPa,高温区域和大应力区域范围较小。由此可知,改变闸片排布方式更能显著降低制动盘温度和应力,并且温度场和应力场分布更均匀。研究结果可为制动盘热性能优化设计提供理论参考。

Analysis and optimization of thermal performance of brake disc of ultra deep mine hoist

When subjected to cyclic frictional thermal load during the emergency braking process, the brake disc of ultra deep mine hoist generates large internal thermal stress. In the meantime, the high temperature can decrease the friction braking performance of brake disc and brake pad and even cause brake disc failure. Aiming at the thermal performance problem of brake disc, based on the heat conduction theory and the finite element analytic method, the three-dimentional finite element model of the brake disc component was built. The thermal stress field during the braking process was simulated by direct coupling method, and the validity of the simulation parameter setting was verified by experiments. The influences of number and arrangement of brake pads on temperature and stress distribution of brake disc under braking condition were studied. The results indicated that the temperature and stress on the friction surface rose sharply firstly, and then dropped slowly during the braking stage, and the temperature had serrated fluctuations. In the braking process, the variation of stress was the same as that of temperature. The maximal temperature of the original brake disc during the braking process was 134.8℃, while the maximal stress was 230.2 MPa. Also, the high temperature and large stress areas were concentrated near the friction surface. The maximal temperature of the brake disc with increased number of brake pads during the braking process was 142.4℃, the maximal stress was 251.1 MPa, and the high temperature and large stress areas were also concentrated near the friction surface. Through optimization of the arrangement of brake pads, the maximal temperature of brake disc was 86.45℃, the maximal stress was 119.1 MPa, and the high temperature and large stress areas concentrated in a smaller range. It could be seen that change of the arrangement of brake pads could significantly reduce the temperature and stress of the brake disc, and the distribution of temperature field and stress field become more even. The research results can provide a theoretical reference for thermal performance optimization design of brake disc.