The top part of one inner bolt which matches the blankhole channel of the outer hollow screw is also conical. The rear is provided with a thread and a tetragonal body for holding.
一与外空心螺钉的盲孔道相匹配的内螺栓，内螺栓的尖端部位亦为锥形，尾部设有螺纹和供握持用的四方体。
2
The blank design principle and method for rolling ring with stepped hole is developed based on the volume flow law and the comparison to the ring rolling experiment is done.
基于阶梯孔环件轧制体积流动规律，提出了阶梯孔环件轧制用毛坯设计原理和方法，并进行了轧制实验验证。
3
Decentraction of the conn-rod small end hole center with the excircle center of the conn-rod small end holeblank, which causes the hole wall of one side getting thin with the strength dropping.