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铁路机车车辆的轮对是高负荷部件,要求有高的安全可靠性。对整体车轮材料强度检验的实施过程在检验规范中规定。这种车轮材料强度检验与机械强度和热负荷检验不同。承受机械负荷的能力是以疲劳强度来检验的。在特定情况下,可以采用由工作强度定义的当量应力来检验。由此表明,由于车轮承受着非常高的总应力循环次数,所获得的检验结果与所采用的应力损伤累积假设密切有关。该假设以韦勒(WHLER)疲劳特性曲线和负荷组合的关系表示。如果采用这种方法,则必须有符合法规的、标准的检验规范。车轮在极限磨耗尺寸下运转时,由于车轮的磨耗会导致负荷的显著增加,所以对轨道状态也有很大影响。轮轨作用力产生的应力将与车轮制造和运行产生的附加应力相迭加。制造应力是指车轮轮圈(轮缘)调质所产生的内应力以及组装时的装配应力。运行附加应力是指由车轮离心力和车轮圆盘制动及闸瓦制动发热所产生的应力。闸瓦制动对车轮材料提出了极高的要求。在这些情况下,今后对车轮强度检验过程的管理及相应的规范应做进一步的改进。通常,除闸瓦制动力以外,轨道作用在车轮上的力和侧向力对车轮工作负荷有很大的影响。亦已证明,运行附加应力相当低。这个论断已被应力分析所证实。
Railway rolling stock wheels are high-load components, requiring high safety and reliability. The whole wheel material strength test implementation process specified in the inspection specification. This wheel material strength test and the mechanical strength and heat load test different. The ability to withstand mechanical loads is checked by fatigue strength. In certain cases, it can be tested using the equivalent stress defined by the working strength. This shows that due to the fact that the wheel is subjected to a very high total stress cycle, the test results obtained are closely related to the cumulative stress damage assumptions used. This assumption is expressed in terms of WHLER fatigue characteristics and load combinations. If you use this method, you must have in line with regulations, standards of inspection specifications. When the wheel is running at the limit wear size, the track condition is also greatly affected by the significant increase in load due to the wear of the wheel. The stress generated by the wheel-rail force will be superimposed with the additional stress generated by the wheel manufacturing and operation. Manufacturing stress refers to the wheel wheel (rim) quenching and tempering caused by the internal stress and assembly of the assembly stress. Additional stress is run by the wheel centrifugal force and wheel disc brake and brake brake the heat generated by the stress. Brake brake on the wheel material made of high requirements. Under these circumstances, future improvements to the management of wheel strength testing procedures and the corresponding codes should be further improved. In general, with the exception of the brake shoe braking force, the forces acting on the wheel and the lateral forces exert a great influence on the wheel work load. It has also been demonstrated that the additional stress at work is quite low. This assertion has been confirmed by stress analysis.