Research on high-end bearings

Bearing accuracy research
High precision is a typical feature of high-end machine tool bearings. The relevant theoretical research on bearing accuracy includes:
Method, the analysis of the influence of parts manufacturing errors, lubrication, etc. on accuracy, the formation mechanism of bearing non-reproducible accuracy, and the influence of working conditions on accuracy.
Bearing damage and failure mechanism
Due to the more complex structure and harsher working conditions, the mutual coupling effect of various factors is more significant, so high-end bearings
The damage and failure mechanisms are far more complicated than conventional rolling bearings. Take the aero engine main shaft bearing as an example, due to the high temperature and high speed
The surface interface damage that occurred under the system caused early failure, and the actual service life of most spindle bearings is far from based on
The life predicted by rolling contact fatigue theory. The early failures of aero-engine main shaft bearings mainly include slippage, injury and wear
Corrosion, scratching pits, cage damage and fracture, etc. These failure problems and the surface of the bearing under harsh working conditions
The interface behavior is closely related. The general bearing failure is characterized by the fatigue judgment caused by the generation and propagation of subsurface cracks,
In the 1940s, Swedish scientists Lundberg and Palmgren proposed the famous theoretical formula for predicting the rolling bearing fatigue life of bearings based on the Hertz contact theory under rolling contact conditions and considering the probability distribution of internal defects in the material.
(Referred to as LP theory), after decades of revisions, an international standard for bearing fatigue life design has been formed, but for
Surface fatigue and wear due to micro-contact damage from surface roughness peaks, damage caused by indentation of hard particles in lubricating oil, and
Surface corrosion and other problems, but there is no widely recognized life prediction model, and the common light load for aero engine spindle bearings
High-speed skidding and rubbing injuries such as failure modes, L-P theory is not applicable at all, and there is no reason to predict the occurrence and degree of injury
On the formula. Therefore, theoretically analyzing and predicting these bearing surface interface failure problems requires rolling fatigue in existing bearings
On the basis of the theoretical framework of mechanics, a cross-scale theoretical model is developed, which goes deep into the microscopic, nanoscopic organization and structure of the subsurface of the material.
Lubrication and adhesion behavior of the contact interface Although the above research has made some progress, but due to the complexity of the internal contact and lubrication of the bearing, there is still much work to be done on the theoretical model and calculation method, such as due to the characteristics of the lubricant Uncertainty and complexity of rolling bearing motion laws, the results of dynamic analysis of rolling bearings are insignificant for design and application: due to incomplete research on the mechanism of bearing heating and heat dissipation, progress in bearing temperature prediction and thermal-mechanical coupling analysis has been slow
Based on the current theoretical development, the well-known foreign bearing companies, combined with the company ’s many years of research and development experience, are committed to more in line with
Development of performance analysis tools for actual bearing operating conditions, such as BEAST software developed by SKF does not use raceway control, etc.
Assuming dynamic simulation, NSK ’s BRAN software discards the assumption of “pure motion” in traditional bearing calculations.
The dynamic multi-function and all-round simulation analysis of the bearing rotation is now available.

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