3.Initial stage of wear and vertical scars
Wearing of contacting surface is an inevitable problem. Determination of the cause of wears and vertical scars is rather challenging because they are generated by overlapping various factors: material of packing, metal finish status on contacting surface, lubricating condition, bearing system, amount of eccentricity, unbalanced load, contamination of fluid. For instance, a lubrication condition consists with many factors: viscosity variance according to nature of operating fluid - initial viscosity - and its temperature shift. Speed of cylinder and frequency also are factors. Here are determination methods of causes focusing on wears and vertical scars.