冷却塔风机齿轮失效的弹性流体润滑分析

Analyses of elastohydrodynamic lubrication for failure gear in cooling tower fan

针对大型冷却塔风机的减速器齿轮失效情况,在校核了圆柱和圆锥齿轮的设计强度的基础上,应用弹性流体润滑的理论,根据可压缩流Reynolds方程所建立的膜厚公式,计算出齿面润滑油膜厚度,并据此研究了工作中的齿轮润滑状况和齿面损伤机理,确定齿轮过早失效的主要原因不是由于齿轮的设计强度不足,而主要是无法在齿面间形成有效油膜,齿轮工作中两齿面有直接接触现象造成,分析出失效的原因是齿轮的润滑不良。并提出相应的解决办法和改进建议,可作为齿轮传动设计和故障分析的参考依据。

Aiming at gear failure of gear box of large cooling tower fan,and based on verifying the design strength of cylinder and bevel gear,the lubricating oil film thickness of tooth surface was calculated with application of elastic fluid lubrication theory and according to film thickness formula established by compressible flow Reynolds equation.On these grounds,the lubrication of the working gear and the damage mechanism of tooth face were researched to make sure that the premature failure of gear was not because of insufficient design strength of gear,but mainly because the effective oil film couldn＇t form between tooth face and the two faces of the working tooth contacted directly.So the reason of gear failure was the poor lubrication of gear.Relevant solution and the improvement suggestion were put forward as the reference for drive design and fault analysis of the gear.