With the increasing soot level contaminating lubricatingoil, the oil viscosity increase and wear of engine components become more severe. And it shortens the life of engine.
柴油机油引起的粘度增长不仅缩短了柴油机的使用寿命，而且增加了零部件的磨损。
2
Bright stock Refined, high viscositylubricatingoil usually made residual stocks by suitable treatment, such as a combination of acid treatment or solvent extraction with dewaxing or clay finishing.