风电机组齿轮箱用润滑油的流变特性

Rheological Properties of Lubricating Oils for Wind Turbine Gearboxes

为对比不同类型风电齿轮箱润滑油的流变特性及润滑性能,利用球-盘点接触光干涉润滑油膜与摩擦力测量装置对不同类型润滑油(PAG油、PAO油和矿物油)的膜厚和摩擦系数进行测量,采用光干涉法测定了润滑油的黏压系数,并分析不同滑滚比和卷吸速度下润滑油摩擦系数的变化规律,结合最小膜厚明确了润滑状态与热效应机制,对比不同类型润滑油斯特里贝克曲线中摩擦系数的变化,分析其润滑性能优劣。结果表明:PAO油和PAG油动力黏度较小,受热效应的影响较小,矿物油受热效应影响最大;PAG油在较低载荷时几乎没有极限剪应力阶段,具有更好的剪切性能;相同工况下,PAG油的摩擦系数最小,润滑性能优于PAO油。

In order to compare the rheological properties and lubrication performance of different types of lubricating oils for wind turbine gearboxes,the film thicknesses and friction coefficients of different types of lubricating oils(PAG oil,PAO oil and mineral oil)are measured on a ball-and-disc point-contact optical interferometric lubricating oil film and friction force measuring device.The viscosity-pressure coefficients of lubricating oils are determined using optical interferometry.The change rule of friction coefficients of lubricating oils under different slip-roll ratios and entrainment velocities is analyzed,and the lubrication state and thermal effect mechanism are clarified in combination with minimum film thickness.The change of friction coefficients in Stribeck curves of different types of lubricating oils is compared to analyze the lubrication performance.The results show that PAO oil and PAG oil have smaller dynamic viscosity and are less affected by thermal effect,while mineral oil is most affected by thermal effect;PAG oil has better shear performance because it has almost no limit shear stress stage under lower load;under same working conditions,the friction coefficient of PAG oil is the smallest,and the lubrication performance is better than that of PAO oil.