The European and American experts through the study of rotating machinery plant found to cause loss of life of rotating machinery valid reasons are mainly three kinds:

One abandoned equipment; second accident equipment; third surface wear equipment components, which account for 15% of the loss of life, 15% and 70%, respectively, while surface wear including physical wear and tear (no lubricant) and fatigue (parts. overload), the former is due to the relative motion of the interface caused by improper lubrication, usually attributed to lubricant selection is incorrect, oxidative degradation of the lubricant, abrasive particles as well as parts of oil overload damage film; the latter in the due to some extent reflects the gap between the shaft and bearing improper adjustment, high stress moving unbalanced and oil particles in the presence of the shaft, and this fatigue is the main reason for the oil particles in high stress. Its mechanism is that the particles pass through the lubricant oil film formed on the surface of strong stress center member, the force due to the small size, particularly stress, which may lead to cracking and peeling of the metal surface. Rotating machinery and equipment usually wear but also with the following factors:

a. Parts of wear and the ratio of the particle diameter and bearing clearance related. The test results showed that when the particle diameter is equal to the bearing running clearance, the maximum wear particle diameter is much larger than or much smaller than the bearing running clearance, the wear will be significantly reduced.

pollution b. lubricating oil (ie particle number) degree will also affect the operation life of the equipment, the more serious pollution, the more particles, the shorter the operating life of the device, on the contrary, the longer operating life of the device.

c. lubricating moisture content increased, reducing the relative operating life of the bearing.

Thus, the lubricant is good or bad quality seriously affected the service life of mechanical rotating equipment, and therefore, it is detected by the oil will be appreciated that the health status of the equipment, and to determine treatment. Currently oil detection methods are mainly routine tests (such as viscosity and oxidation stability, etc.), spectroscopy, particle counter analysis method.

Although routine testing oil may have some physical properties of the oil, familiarize yourself with the oil itself, but this method of equipment wear very limited explanatory power; spectral analysis of oil in a variety of metals can be quantitatively analyzed, but the particle diameter detection of less than 5Lm effective, and can not explain the particle shape and size, it can not indicate the cause of the generation of particles and the like; particle counter method can give the number and size distribution of all kinds of particles, but can not distinguish between the various types of impurities, as well as wear and tear the difference between particles and other impurities.