基于油气润滑的超高转速电主轴轴承润滑性能的试验研究

Experimental Study of the Lubricating Performances for Electric Spindle Bearings Running in Ultra High Speed Lubricated by Oil-air

超高转速条件下主轴轴承内部的润滑特性,是制约电主轴所能够达到的最高转速和影响其动态稳定性的主要因素之一。在油气润滑条件下,利用超高转速电主轴结构,通过改变供油量、转速、轴向预载荷等状态参数,测试反映主轴轴承润滑性能的油膜电阻和轴承部位的温度,对轴承内部的润滑状态性能进行试验研究。结果表明,转速和供油量是影响轴承内部润滑油膜电阻和轴承温升的主要因素,对应于某一转速等特定工况,总存在一个最佳供油量,使轴承能够处于最佳润滑状态;在超高转速条件下,轴承内部会出现严重的"乏油"现象,易导致润滑性能变差、轴承工况条件恶化等。

The lubricating performance is one of the main factors to limit the increase of spindle bearing speed and influence the dynamic stability of the spindle bearings running in ultra high speed. Under the oil-air lubricating condition the lubricating performances of the ultra high speed electric spindle were studied by changing the oil-supply, the working speed, the axial preload of the bearings and so on, and measuring the resistance of the oil film and the temperature of the bearing which affect the lubricating performances of the bearings. The results show that the working speed and the oil-supply are the important factors affect the lubricating performances of the spindle bearings, and in a speed there will be an oilsupply that makes the bearing be in the optimal lubrication state. In ultra high speed, it could appear serious stared phenomenon in bearings.