汽车磨合期与正常使用期的发动机摩擦学状态监测

Tribological Condition Monitoring of Engine of Automobile at Running-in and Normal Working Stage

应用理化分析和铁谱分析方法,对汽车磨合期与正常使用期的发动机摩擦学状态进行了对比试验研究。结果表明:磨合期发动机润滑油粘度稍降,而正常行驶期粘度略升,变化趋势相反;磨合期和正常使用期润滑油的闪点基本相同,有略降趋势,而燃点基本不变;磨合期润滑油酸值基本不变,而正常行驶期酸值增加幅度大,可作为汽车正常行驶期主要监测指标;磨合期磨损烈度指数和大磨粒个数明显高于正常行驶期,可作为监测汽车发动机磨合状态的主要指标,并可监测汽车正常行驶期发动机异常磨损和预测剩余寿命。

Physicochemical property analysis and ferrography were applied to study the tribological condition of automobile engine at running-in stage and normal working stage. The result shows that the viscosity of engine oil decreases slowly at running-in stage and reversely at normal working stage, the flashing point is similar with a little decrease and the ignition point remains constant at both stages. At running-in stage, there is no big change in acid value and it dramatically rises at normal working stage, thus the acid value can be considered as main index to monitor tribological condition. At running-in stage,the severity of wear index and the counts of big abrasion particle are obvious higher than those at normal working stage, therefore they might be an important index to evaluate running-in effect, monitor abnormal abrasion at normal working stage and predict life-span of engine.