论文部分内容阅读
应力在各种类型曲拐上的分布可以用应力集中系数来表示。但是用曲拐上开孔或开穴来減小应力的方法研究得还很少。因此,有时孔或穴开得不得法会得出相反的效果。应用光测弹性方法和应变测量来研究工述問題,可以提供許多有用的經驗。通过在实际运轉的柴油机上所进行的测量,能夠确定曲轴各危險点的应力变量。可以将机器运轉时产生的最大应力值与根据簡化假設而得的结果进行比較。在試件和全尺寸曲拐上进行的研究表明:即使很小的微观裂缝、缎造缺陷和非金属杂质也将使鋼的动力性能大大降低。材料的断面收缩提供了确定疲劳极限的依据。最后,对如何从工艺观点改善曲軸疲劳強度的方法作了闡述。
Stress distribution on various types of crank can be expressed by stress concentration factor. However, there are few studies on ways to reduce the stress by using holes or holes in the crank. Therefore, there are cases where the hole or hole can not be given the opposite effect. The use of photometric elastic methods and strain measurements to study problems can provide many useful lessons. Through the actual operation of the diesel engine carried out on the measurements, to determine the dangerous point of the crankshaft stress variables. The maximum stress generated when the machine is running can be compared to the result based on a simplifying assumption. Research conducted on test coupons and full-scale crankcases has shown that even small microscopic cracks, satin defects and non-metallic inclusions will result in greatly reduced dynamic performance of the steel. The cross-sectional reduction of the material provides the basis for determining the fatigue limit. Finally, how to improve the fatigue strength of crankshaft from the viewpoint of technology is described.