摘要
液体静压电主轴系统的热变形严重影响机床加工精度,有必要对电主轴系统热变形的影响因素进行分析,以减小系统的热变形量。利用有限元法,分析在工艺参数和结构参数不同取值条件下某液体静压电主轴系统的热变形情况,重点分析冷却水流量、轴承供油压力、主轴转速、轴承结构参数对主轴热变形的影响。结果表明,电主轴系统的最大变形出现在主轴前端安装砂轮处;冷却水流量和供油压力的改变对主轴前端面径向最大热变形的影响规律显示,当冷却水流量和供油压力达到一定值时,系统的热变形已得到有效控制,若再增大冷却水流量和供油压力,热变形量减少的幅度较小;在不同的主轴转速下,润滑油的流动状态不同,润滑油在紊流条件下的主轴前端面径向最大热变形超过层流条件下的2倍。运用均匀设计试验,得到轴承长径比和轴承轴向封油边长度的优化参数值,使主轴前端面径向最大热变形控制为最小。
The thermal deformation of the hydrostatic motorized spindle affects seriously machining precision,so it is necessary to analyze the effect factors of the thermal deformation of motorized spindle system. The process parameter and structural parameter are significant factors,such as the flow-rate of cooling water,the input pressure of bearing oil,the spindle speed and the bearing＇s structural parameter. The results show that the maximum deformation of the motorized spindle system was in the place where the grinding wheel was installed. The variations of the flow-rate of cooling water and the input pressure of bearing oil affected the maximum deformation on the front surface of the spindle. When the flow-rate of cooling water or the input pressure of bearing oil was at a certain value,the thermal deformation was brought under effective control. If the flow-rate of cooling water or the input pressure of bearing oil increased more,the reduction of the thermal deformation was less. As the speed changed,the flow condition of the bearing oil was different. The maximum deformation of the spindle ＇s front surface in the condition of turbulent flow was more than two times of that in laminar flow. The bearing＇s length-to-diameter ratio and the length of bearing axial sealing edge were optimized,which minimized the maximum radical thermal deformation on the front surface of the spindle.
出处
《机械强度》
CAS
CSCD
北大核心
2017年第1期154-159,共6页
Journal of Mechanical Strength
基金
国家重大科技专项(2011ZX04016-041)资助~~
关键词
静压轴承
参数优化
电主轴
热变形
Hydrostatic bearings
Parameter optimization
Motorized spindle
The thermal deformation
