将机油滴在白纸上,油内各种杂质会随着油向四周扩散.杂质的粒度不同,扩散的远近也不同,在纸上形成深浅不同的环形斑痕.斑痕的核心是油内粗颗粒杂质的沉积物集中的地方,由核心区颜色的深浅可以粗略地判断油被污染的程度.核心区外围是悬浮在油内的细颗粒杂质向外扩散留下的痕迹.机油中有清净分散添加剂时扩散的宽度就比较大,而且四周呈花边状.扩散区外是油痕,随着使用时间的增加,油发生氧化,颜色由浅黄色变为棕红色.色泽越暗,表明油的氧化越厉害. The oil drops on the white paper, the oil will be a variety of impurities with the oil spread around the impurities of different particle size, diffusion is also different from the depth of the paper to form a different depth of the scar. The core of the scar is coarse particles of oil Impurities where the sediment concentration, the color depth of the core area can be roughly judged by the degree of oil pollution. The core area is surrounded by the suspension of fine particles of oil in the outward spread of the traces left in the oil dispersion additive clean When the proliferation of the width is relatively large, and surrounded by a lace-like shape. Outside the diffusion area is the oil marks, with the use of time increases, the oil oxidation occurs, the color from light yellow to brown red color darker, indicating that the oil oxidation Amazing