The difference between innerfriction angel of sandy soil and natural slope angel of sandy soil is also put forward in this paper.
本文论述砂土内摩擦角的测定方法，及砂土内摩擦角与砂土天然坡角的区别。
2
For tapered roller large end and sliding friction between the inner wall, the speed limit is often lower than the same size cylindrical roller bearings.
因圆锥滚子大端与内圈挡边之间滑动摩擦，其极限转速往往低于同尺寸的圆柱滚子轴承。
3
Teflon Piston-ring integrated with piston, not only reduce the friction and noise, but also avoid inner-leakage.