某型装载机驱动桥内齿轮失效分析及技术改进

发布时间：2018-06-27 20:21

本文选题：内齿轮 + 失效分析　；参考：《广西工学院》2012年硕士论文

【摘要】：装载机驱动桥内齿轮是装载机行走机构中的重要零件之一，主要用来传递运动和动力。某型装载机在服役过程中，驱动桥内齿轮经常出现失效的情况，这不但影响了机器的正常使用，而且给用户和企业都带来了一定的经济损失。失效分析是可靠性工程的重要组成部分，是提高产品质量的有效途径之一。通过对失效件进行失效分析，找出产品失效的原因，可以有针对性地提出改进建议和预防措施，，提高产品质量，延长其使用寿命，且可增强装载机服役的安全性和可靠性。因此，对失效的内齿轮进行合理的失效分析，具有十分重要的意义。本文通过对失效件进行收集、统计、归纳，得出内齿轮的失效模式为：轮齿根部疲劳断裂和沿插齿刀退刀槽断裂。通过实验手段，借助于硬度计、光谱分析仪、金相显微镜、扫描电镜等试验设备，对内齿轮断口的宏观和微观形貌进行了全面地检测和分析，同时对内齿轮原材料质量、热加工质量、机加工质量也进行了系统的分析和总结，找出了导致内齿轮早期断裂失效的原因。针对失效的原因，提出了一系列的技术改进措施，通过这些措施可以有效控制内齿轮在制造过程中的加工质量，防止其发生早期的失效破坏。本文利用VDI2737-2005标准对内齿圈进行安全系数的校核，得出了内齿圈齿根弯曲疲劳强度安全系数设计过低的结论，并利用有限元软件Ansys对内齿圈进行仿真分析，验证了理论计算结论的正确性。在此基础上，通过对内齿轮有限元分析得出：内齿轮齿根弯曲疲劳安全系数设计过低，达不到齿轮设计标准中齿根疲劳安全系数的设计要求，这是导致内齿轮从齿根断裂的主要原因之一。以提高内齿轮齿根弯曲疲劳强度安全系数为主要目标，在保证不影响驱动桥结构设计及行星齿轮系统结构的前提下，选取不同齿根圆角半径和不同的内齿圈壁厚，按照VDI2737-2005标准分别计算，得出了计算齿根弯曲疲劳安全系数的变化情况，由此提出了内齿轮结构的改进建议，并利用有限元软件进行进一步的仿真分析，验证了改进建议下内齿轮结构的合理性。
[Abstract]:The internal gear of the loader drive axle is one of the important parts in the loader walking mechanism, which is mainly used to transfer motion and power. During the service of a certain type of loader, the gear in the drive axle often appears failure, which not only affects the normal use of the machine, but also brings certain economic losses to the users and enterprises. Failure analysis is an important part of reliability engineering and one of the effective ways to improve product quality. Through the failure analysis of the failure parts, the causes of the product failure can be found out, and the improvement suggestions and preventive measures can be put forward in order to improve the product quality, prolong its service life, and enhance the safety and reliability of the loader in service. Therefore, it is of great significance to analyze the failure of internal gears reasonably. In this paper, the failure modes of internal gear are obtained by collecting, statistics and summing up the failure parts. The failure modes are: fatigue fracture at the root of the gear and fracture of the receding groove along the gear shaper. By means of experiment, with the help of hardness meter, spectrum analyzer, metallographic microscope, scanning electron microscope and other test equipment, the macroscopic and microscopic morphology of internal gear fracture was comprehensively detected and analyzed, and the raw material quality of inner gear was also analyzed. The hot machining quality and machining quality are systematically analyzed and summarized to find out the causes of early fracture failure of internal gears. Aiming at the causes of failure, a series of technical improvement measures are put forward, which can effectively control the machining quality of internal gear in the manufacturing process and prevent its early failure. In this paper, VDI2737-2005 standard is used to check the safety factor of inner gear ring, and the conclusion is drawn that the safety factor of internal gear tooth root bending fatigue strength is too low, and the internal gear ring is simulated and analyzed by finite element software Ansys. The correctness of the theoretical calculation results is verified. On this basis, through the finite element analysis of internal gear, it is concluded that the design of bending fatigue safety factor of internal gear tooth root is too low to meet the design requirements of tooth root fatigue safety factor in gear design standard. This is one of the main reasons that cause the internal gear to break from the root of the tooth. In order to improve the safety coefficient of bending fatigue strength of internal gear root, and without affecting the design of drive axle and the structure of planetary gear system, different tooth root radius and different wall thickness of inner gear ring are selected. According to VDI2737-2005 standard, the change of bending fatigue safety factor of tooth root is obtained, and the improvement suggestion of internal gear structure is put forward, and the further simulation analysis is carried out by using finite element software. The rationality of the inner gear structure is verified.
【学位授予单位】：广西工学院
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：TH243

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