环烷基基础油和石蜡基基础油混合中的自降凝现象研究

针对润滑油基础油混合中出现的自降凝现象，即混合油品倾点低于两种组分油品各自倾点的现象，将不同环烷基基础油和石蜡基基础油调合，测定其低温性能，并结合油品理化性质进行分析，提出自降凝现象的作用机理。结果表明：自降凝现象在环烷基原油精制油品与石蜡基原油精制油品间混兑时比较明显；两种油品混合时，自降凝现象的明显程度取决于基础油类型、两种油品间的倾点差距及运动黏度（100 ℃）差距，3种因素对自降凝的影响依次减弱。两种油品的凝固方式差别越大、倾点越接近、运动黏度（100 ℃）越接近，则自降凝现象越明显。KN4010为环烷基基础油，HVIP8为石蜡基基础油，两者倾点都是-24 ℃，运动黏度（100 ℃）接近，其混合油品的倾点可以降低到-42 ℃。

POUR POINT REDUCTION PHENOMENON OF NAPHTHENIC BASE OIL AND PARAFFINIC BASE OIL MIXTURE

The paper reveals a phenomenon that the pour point of mixed base oil is below the pour point of each component of the mixture. The phenomenon is obvious when naphthenic base oil is mixed with paraffinic base oil. Pour point and other physicochemical properties of mixtures with different naphthenic base oil and paraffinic base oil ratios and component were all analyzed. A hypothesis for the phenomenon was proposed based on the carbon structures of base oils and mechanism of pour point depressant, combined with the analysis of oil properties. The obvious degree of the phenomenon depends on the types, the pour point difference and the viscosity (100 ℃) difference of the two components. Tests show that the influence of three factors on the low temperature performance is in turn. The greater the solidification mode difference, the closer the pour point and viscosity (100 ℃) of two components, the more obvious of the phenomenon is. KN4010 is naphthenic base oil and HVIP8 is paraffinic base oil. The pour points of the two component are both -24 ℃, their viscosities of 100 ℃ are close, the pour point of the mixed oil of two component can be -42 ℃.