游梁式抽油机曲柄销结构与工艺改进研究

Structure and Technology Improvement for Crank Pin in Beam Pumping Unit

在抽油机事故中,曲柄销过早损坏占事故总数的30%以上。采用常规的分析方法对曲柄销所作的改进,不能解决其过早损坏问题。利用微动磨损理论,分析曲柄销损坏特点,得出曲柄销过早损坏和微动有关。为了提高曲柄销寿命,在设计时,除保证通过力学计算和结构需要确定的直径、长度、螺距等主要参数外,还应重视其他细小部分参数,如锥面上空刀槽的尺寸和过渡结构、锥面锥度、螺纹退刀槽圆角半径等,它们对微动影响较大。同时,应保证曲柄销加工时特殊的工艺要求。

In the accident of pumping unit,the premature failure of the crank pin amounts to more than 30%. The improvement to the crank pin,using conventional analysis method,cannot solve the premature damage problems. Fretting wear theory was used to analyze the characteristics of the crank pin damages,and that the premature damage of the crank pin was associated with the fretting could be gained. In order to prolong the service life of the crank pin,excepting the diameter,length,pitch determined by the mechanical system and structure requiring,more attention should be paid to the parameters of other small parts,such as the size and the transition structure of the clearance groove on the pyramidal face,conical taper,and the radius of thread tool withdrawal groove,etc,which deeply influenced it. At the same time,the special technical requirements of the crank pin should be assured during the course of working.