1. Chemical reactions

Components of grease base oil prices and thickener) because of the action of diffusion, heat and air, qualitative change is likely to produce air oxidation, base oil price by air oxidation to form a small amount of organic matter, aldehyde, ketone and lactone, thickener in oleic acid, organic chemistry, metal salt may be dissolved and produce a small amount of organic matter, etc., thus, Cause the acid and alkali substance (the acid value of grease expands) cause the erosion of the lubricated parts until rust, and lose the lubrication and safety protection effect.

2. Change of state of matter

Because the effect of mechanical equipment makes the structure of grease worse or even destroyed, the consistency of grease mortar is reduced, the actual lubrication effect is worse, or because the sealing standard of mechanical equipment lubrication parts is not good, resulting in the infiltration of soil, residue and water in the grease and the grease quality is worse.

Identification way: grease human eyes or touch dust, mechanical equipment residue, or because of infiltration of water grease emulsion and whitening, light, or mortar consistency significantly reduced, or there is significant grease rancidity odor, can show that the quality of grease change.

Using analytical chemistry, the most immediate identification is to take a few applied samples and measure them with an NIR spectrometer for a 1720cm-1 digestion and absorption peak. Or the ratio of 1710cm-1 and 1378cm-12 digestion and absorption peaks of the conversion carbonyl index of the adsorption peak before and after application of the sample was measured. Or immediately measure the acid value of the sample, if the acid value exceeds 1.0mgKOH/g, the table establishes that the grease has gradually changed