共查询到19条相似文献,搜索用时 109 毫秒
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针对渗碳淬火20CrMnTi齿轮在磨齿时易产生磨削裂纹而报废的现象,通过多年的生产实践,总结和归纳和渗碳淬火齿轮磨削裂纹产生的原因和防止裂纹的工艺措施。 相似文献
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针对渗碳淬火钢齿轮在磨齿时,易产生磨削裂纹而报废的现象,通过多年的生产实践。总结和归纳渗碳淬火齿轮磨削裂纹的产生原因和防止工艺措施。 相似文献
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从磨削过程中磨削热、磨削力、齿面应力状态及磨削之前的渗碳淬火工序所得的显微组织等方面,阐述裂纹产生的原因.并提出从磨削工艺上降低磨削温度、从淬火处理上改善齿轮表面应力状态等措施,可有效控制和防止该齿轮的磨削裂纹的产生。 相似文献
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陈永道 《机械制造与自动化》2013,42(4)
根据典型大型渗碳淬火齿轮在磨削过程中出现裂纹的形态、数量以及分布特点,从渗碳淬火品质和磨削加工两个方面分析了磨削裂纹产生的原因,通过分析比较有磨削裂纹和无磨削裂纹处齿面的金相组织、有效硬化层深,得出致使局部出现磨削裂纹的主要原因是磨削前局部(出现磨削裂纹处的)齿形齿向出现了不规则变形(畸变高点),而磨齿校基准时,没有找到此畸变高点,导致在畸变高点附近的磨削切削量太大,且砂轮在靠近齿根处的线速度最大,致使在畸变高点附近的齿根处产生较大的拉应力,从而出现磨削裂纹. 相似文献
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试验分析了渗碳主轴产生磨削裂纹的原因。指出严格控制渗碳表面碳浓度、合理选择淬火温度和回火规范对防止磨削裂纹的产生有着重要作用。 相似文献
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大模数齿轮平行于磨削方向磨齿裂纹原因分析 总被引:1,自引:0,他引:1
根据磨齿裂纹的形态,判断出两类不同形态的裂纹源于截然不同的机理;找出大模数渗碳淬火齿轮齿面产生的和磨削方向平行的条数少、长而深的磨齿裂纹是由齿面上的巨大拉应力引起的。通过对渗碳淬火齿轮齿面产生残余应力的机理分析,证明齿面产生残余拉应力的可能性是存在的。齿面拉应力的存在可以较完满地解释产生所提磨齿裂纹的各种现象。最有效的预防措施是通过提高淬火油温控制心部表层马氏体转变的顺序,阻止表层在心部组织转变前产生转变,以保证最终在齿面形成残余压应力。 相似文献
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风机行星齿轮系统齿轮裂纹故障诊断 总被引:1,自引:0,他引:1
针对风力发电机实际行星齿轮系统,由于幅值及相位调制现象(各种制造误差不可避免等原因所导致)带来的故障诊断难题,搭建了含各种制造误差的动力学模型。模型考虑了出现裂纹故障以后,故障对时变啮合刚度以及传递误差的影响,通过数值求解,对比行星轮、太阳轮以及齿圈出现故障后与正常齿轮系统的包络谱结构特性,总结了故障特征频率。在风力发电机齿轮箱实验台上进行裂纹故障试验验证,结果表明所总结的故障特征频率可以作为风力发电机裂纹故障诊断及定位的依据。 相似文献
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Pitting phenomenon in gears was studied using a power recirculating type test rig. The study of gear failure by pitting was made by micro-photographic analysis. Microscopical examination of pitted areas revealed transcrystalline cracks as well as intergranular cracking, a mode of failure not previously reported. 相似文献
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This paper describes a magnetic detection system which has been developed for continuous monitoring of the surfaces of a system running under conditions where fatigue cracks are likely to occur. Experiments are described involving a disc-on-disc machine (which was made to simulate the contact conditions between gear teeth). The method is shown to be capable of detecting (i) initial surface fatigue cracks and (ii) the eventual pitting failure. It is also possible to use the detected signals to shut down the machine in order to facilitate microscope examination of the flaws to be carried out as soon as they are first detected.The method is compared with previously published attempts to detect and locate cracks and pits. The potentialities of the technique are also discussed. 相似文献
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《Mechanical Systems and Signal Processing》2007,21(1):177-192
For constant loading and speed conditions, the principal sources of vibration excitation arising from meshing gears, characterised by the “static transmission error” (STE) excitation, are geometric deviations of the working surfaces of the teeth from equi-spaced perfect involute surfaces, and tooth/gear body elastic deformations. Changes in these two sources caused by tooth-bending-fatigue damage on one or a few teeth are manifested primarily in the rotational-harmonic content of the STE of each individual damaged gear of the meshing pair, and are most effectively detected in the time domain. The optimum number of gear rotations to be used in synchronous averaging is specified, along with how such synchronous averaging can be used to eliminate the effects of the mating gear in the case of “hunting tooth” gear pairs, and to minimise these effects otherwise. Precision measurements made on the teeth of a gear failed in a tooth-bending-fatigue test strongly suggest that whole-tooth plastic deformation—i.e. yielding, rather than changes in tooth stiffness caused by tooth-root cracks, is the principal source of detectable damage in the case of tooth bending fatigue. Such plastic deformations are geometric deviation STE contributions. Differences in gear materials, materials processing, and gear operating properties may significantly affect the amounts of such plastic deformations before tooth breakage and the operating duration between initial damage detection and tooth breakage, thereby suggesting the need for testing to determine such dependencies. 相似文献
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齿轮状态监测和识别方法的研究 总被引:4,自引:1,他引:3
基于一致度分析,本文对常用的齿轮状态监测指标进行了优化。通过对优化监测指标集的主分量分析,给出了主分量识别和监测指标,实现了对齿轮状态的识别和监测,尤其是对齿轮出现裂纹的监测。 相似文献
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A crack fault is one of the damage modes most frequently occurring in gears. Identifying different crack levels, especially for early cracks is a challenge in gear fault diagnosis. This paper aims to propose a method to classify the different levels of gear cracks automatically and reliably. In this method, feature parameters in time domain, specially designed for gear damage detection and in frequency domain are extracted to characterize the gear conditions. A two-stage feature selection and weighting technique (TFSWT) via Euclidean distance evaluation technique (EDET) is presented and adopted to select sensitive features and remove fault-unrelated features. A weighted K nearest neighbor (WKNN) classification algorithm is utilized to identify the gear crack levels. The gear crack experiments were conducted and the vibration signals were captured from the gears under different loads and motor speeds. The proposed method is applied to identifying the gear crack levels and the applied results demonstrate its effectiveness. 相似文献
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服务机器人关节采用驱控一体化集成设计,并且传动系统采用小模数变位齿轮。关节频繁运动容易导致齿轮传动系统产生裂纹,裂纹引起刚度变化从而影响整个系统的动态特性。根据变位齿廓建立变位齿轮裂纹刚度计算模型,分别研究变位系数、多种裂纹形式对时变啮合刚度的影响;其次利用集中参数法构建了机器人关节机电耦合平移—扭转动力学模型,并将驱动电机的电磁特性、齿侧间隙等因素考虑入方程中;最后通过统计学分析裂纹对传动系统的影响。研究结果表明:正变位使刚度增大,负变位反之;双侧裂纹对刚度的影响明显大于单侧;随着裂纹加深,时变啮合刚度加速降低;随着传动系统级数的增加,裂纹对传动系统的影响逐渐减弱。研究结果为变位齿轮传动系统裂纹故障诊断提供理论基础。 相似文献