取样量对润滑油中微量水分检测结果的影响

研究取样量对润滑油中微量水分测定结果的影响。基于卡尔·费休滴定法,在选定的测量条件下,用发生电极为有隔膜的自动库仑水分仪对基础油、有机热载体油、压缩机油、膨胀机油等新油和发动机油、汽轮机油、涡轮机油、压缩机油、齿轮油、液压油、导热油、船用油、电器绝缘油、风动工具油、金属加工油等在用油在0.1~2.0 g内各取9组不同质量的样品进行测定,得到了润滑油中微量水分准确测定所需的取样量。实验结果表明,新油取样量大于1.0 g,在用油取样量在1.0~1.5 g范围内,可以准确测定润滑油中微量水分含量。测定结果的相对标准偏差为0.83%~3.51%(n=10),样品加标回收率为95.0%~103.0%。在选择的取样量下,该方法具有良好的精密度、准确度,可连续测定多个样品,满足测定需求。

Influence on Test Result of Trace Water in Lubricating Oil by Sample Quality

The influence on determination result of trace moisture in lubricating oil by sampling quantity was studied. Based on the method of Karl Fischer titration,under the selected measurement condition,using the automatic coulomb moisture meter with the electrode of a diaphragm between the anode and cathode compartments was used to determine trace water in new oil of base oil, heat transfer fluids oil, compressor oil, expansion of the oil et al and old oil of engine oil, steam turbine oil, turbine oil, compressor oil, gear oil, hydraulic oil, hot oil, bunker oil, electric insulation oil, pneumatic tool oil, metal processing oil et al by taking 9 groups of different quality of 0.1-2.0 g samples, the sampling quantity for determination of trace water in the lubricating oil was obtained. The experimental results showed that when sample quality of new oil was more than 1.0 g,sample quality of old oil was in the range of 1.0-1.5 g,the trace water content in the lubricating oil could be determined accurately. The relative standard deviations of detection results were 0.83％-3.51％(n=10),the recoveries were 95.0％-103.0％. Under the selected sampling volume, the method has good precision and accuracy, it can measure multiple samples continuously and meets the demand of measurement.