按机械工作条件选用润滑油原则
Principle of selecting lubricating oil according to mechanical working conditions
负荷
load
负荷大，应选用粘度大或油性、极压性好的润滑油。反之，负荷小，应选用粘度小的润滑油。间歇性的或冲击力较大的机械运动，容易破坏油膜，应选用粘度较大或极压性较好的润滑油，或用这种润滑油制成的锥入度较小（较硬）的润滑脂。
If the load is large, the lubricating oil with high viscosity or good oiliness and extreme pressure should be selected. On the contrary, the load is small, should choose low viscosity lubricating oil. It is easy to damage the oil film in intermittent or large impact mechanical movement. The lubricating oil with higher viscosity or better extreme pressure property or the grease with smaller cone penetration (harder) made of this lubricating oil should be selected.
速度
speed
速度高，需选用粘度较小的润滑油或用粘度较小的润滑油制成的润滑脂；反之，则用粘度较大的润滑油或用粘度较大的润滑油制成的润滑脂。对于高速滚动轴承的选脂，为了补足所有脂的机械安定性和成渠性，以及克服离心力的作用，最好选用稠度较大的3号润滑脂；对一般转速不太高的轴承来说，为了降低轴承的转矩，特别是启动转矩，则尽可能选用低稠度的润滑脂。
If the speed is high, it is necessary to select the lubricating oil with lower viscosity or the grease made from the lubricating oil with lower viscosity; otherwise, it is necessary to use the lubricating oil with higher viscosity or the grease made from the lubricating oil with higher viscosity. For the grease selection of high-speed rolling bearing, in order to make up for the mechanical stability and channeling of all grease, and overcome the effect of centrifugal force, it is better to choose the grease with higher consistency No. 3; for the general bearing with low rotating speed, in order to reduce the torque of bearing, especially the starting torque, it is better to choose the grease with lower consistency as far as possible.