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Understanding the influence of bearing component manufacturing errors and roller number on the rotational accuracy of rolling bearings is crucial in the design of high precision bearings. The rotational accuracy of an assembled bearing is dependent upon roller number and manufacturing error of the bearing components. We propose a model for calculating the rotational accuracy of a cylindrical roller bearing; we experimentally verified the effectiveness of the model in predicting the radial run-out of the inner ring proposed in the previous paper in this series. We sought to define the key contributing factors to the rotational accuracy by studying both the influence of the coupling effect of the roller number and the influence of the manufacturing errors in the inner raceway, outer raceway, and rollers on the motion error. The model and results will help engineers choose reasonable manufacturing tolerances for bearing components to achieve the required rotational accuracy.

As the rotation of roller bearings is carried out under geometrical constraint of the inner ring, outer ring and multiple rollers, the motion error of the bearing should also be resulted from geometric errors of bearing parts. Therefore, it is crucial to establish the relationship between geometric errors of bearing components and motion error of assembled bearing, which contributes to improve rotational accuracy of assembled bearing in the design and machining of the bearing. For this purpose, considering roundness error and dimension error of the inner raceway, the outer raceway and rollers, a prediction method for rotational accuracy of cylindrical roller bearings is proposed, and the correctness of the proposed prediction method is verified by experimental results. The influences of roller's geometric error distribution, roller's roundness error and the number of rollers on the runout value of inner ring are investigated. The results show that, the roller arrangement with different geometric errors has a significant impact on rotational accuracy of cylindrical roller bearings. The rotational accuracy could be improved remarkably when multiple rollers with different dimension error are distributed alternately according to the size error. Even-order roundness error of rollers has a significant effect on the rotational accuracy, and the decrease level depends on the orders of roundness errors of bearing parts and the number of rollers. But odd-order roundness error of rollers has almost no effect on the rotational accuracy. The rotational accuracy of assembled bearing would be significantly improved or decreased when even order harmonic of rollers and the number of rollers satisfy specific relationships. The greater the order of roundness error of the rollers, the more severe the influence of the roller number on rotational accuracy of assembled bearing. The rotational accuracy can not be always improved with the increase of the number of rollers.

It is a stringent requirement for China to develop the technology on the measurement for the unavoidable micro residual unbalance of tiny cylindrical rollers of the high-speed precision bearings, which are widely equipped on high-end advanced equipment. During the measurement process, the vibration response excited by micro unbalance, which is easy to be messed up with background noise, is hard to be detected and a soft support mounting bracket is proposed to enhance the amplitude of vibration response, while maintaining the steady rotation of test roller. Accordingly, a dynamic model of both test roller and mounting bracket is constructed to analyze and simulate the vibration response. Furthermore, a μm level high precision laser-based non-contact measurement system consisting of a roller rotation drive system and a vibration signal acquisition system is developed to measure the synchronized vibration of the unbalance. Finally, by comparing experiment results of a standard roller with a special prepared unbalanced roller and comparing experiment results with simulated results, the validity of the proposed measurement method is verified.

Aiming at the problem that the measuring precision of thin-walled bearing's outer diameter in our country is not high enough to match the precision and capability of production completely, on the basis of studying the principle of contact and non-contact measurement at home and abroad, the characteristics of thin-walled bearings with high precision and high surface quality are analyzed. A new method of measuring external diameter is proposed by using IFS2403-0.4 high precision spectral confocal sensor produced by German Iridium Company as measuring tool. It not only ensures the surface quality of the measured parts, but also reduces the mechanical errors caused by the mechanical structure and vibration. At the same time, it can effectively avoid the rotary errors and improve the measuring accuracy. Finally, the experimental results show that the method is simple, efficient and highly accurate, and can be used for production.

The antifriction bearing is the basic component in modern machine which kinematic accuracy affects directly machine performance. Besides influenced by the design, manufacture and environment, it is more important that the kinematic accuracy of bearings is influenced by dimension and shape precisions of inner raceway, outer raceway and rollers. For cylindrical roller bearing, the principal index of the kinematic accuracy is the radial run-out of the bearing inner-outer ring. The dimension-shape error of the components and interaction among them can induce the radial run-out of the bearing. There are dependent relationships between the bearings kinematic accuracy and component geometrical precision which actions are very complicated and extremely difficultly described by mathematical formula. But, the component geometrical error and the radial run-out of the bearing inner-outer ring follow mathematical statistic law and have their distribution characteristics. So, the joint copula distribution function can be introduced to establish the transmit relationships that join the radial run-out of the bearing to multiple components geometrical precision distribution. Based on the copula estimation of distribution algorithm, the mathematic modeling of the run-out of inner-outer ring can be built to forecast bearings kinematic accuracy.

According to the geometrical characteristics of cylindricity error, a method for cylindricity error evaluation using Geometry Optimization Searching Algorithm (GOSA) has been presented. The optimization method and linearization method and uniform sampling could not adopt in the algorithm. The principle of the algorithm is that a hexagon are collocated based on the reference points in the starting and the end measured section respectively, the radius value of all the measured points are calculated by the line between the vertexes of the hexagon in the starting and the end measured section as the ideal axes, the cylindricity error value of corresponding evaluation method (include minimum zone cylinder method (MZC), minimum circumscribed cylinder method (MCC) and maximum inscribed cylinder method (MIC)) are obtained according to compare, judgment and arranged hexagon repeatedly. The principle and step of using the algorithm to solve the cylindricity error is detailed described and the mathematical formula and program flowchart are given. The experimental results show that the cylindricity error can be evaluated effectively and exactly using this algorithm.

A new method for roundness error evaluation using polar coordinate system, named as polar coordinate transform algorithm (PCTA), was presented in this paper. The algorithm first allocates a circular region around the least square circle center following certain rules, then calculates the polar radius for all measured points by translating polar coordinate system to each point in the region in turn, and finally obtains minimum circumscribed center point, maximum inscribed center point and minimum zone center point from comparing each polar radius relative to each polar coordinate system. With accurate center point, the algorithm could give more accurate roundness evaluation. In the paper, the process of PCTA was described in detail including the algorithm formula and flowchart. Theoretical calculation and testing results show that PCTA can evaluate roundness error effectually and accurately.

For the rotary motion of a rolling bearing implemented by bearing components under geometric constraints, the rotational accuracy of assembled bearing should also be the result of interaction among geometric errors of bearing components. Therefore, it is significant to research the relationship between geometric errors of bearing components and rotational accuracy of assembled bearing for the design and prediction of bearing accuracy. An accuracy prediction method is proposed to study how the geometric errors of bearing components affect the radial runout of outer ring of cylindrical roller bearings in this article. Furthermore, the calculation model for the orbit of outer ring center is established from which the radial runout of outer ring can be predicted while dimension and roundness errors of raceways and rollers are given arbitrarily. Theoretical algorithms with two typical shapes of outer raceway are deduced to verify the prediction method. In addition, a test on the radial runout of outer ring in a cylindrical roller bearing is performed. The results indicate that prediction results are in good agreement with experimental and analytical results.

This paper describes a calculation model for pre-stressed bolted joints used to connect turntable bearing to the flanges. A traditional pre-stressed bolted joint calculation model is described and its insufficiencies for the direct application on turntable bearings are pointed out. The suggested stress analysis is done by modeling the most loaded single bolt segment of the turntable bearing assembly, applying the preload and the working load on it. The alternating stress in the bolt is done by finite element analysis. The results show that the alternating load of the bolt is significantly decreased and is lower than the fatigue limit of the bolt under the condition of the larger tightening force. Therefore, it should be possible to increase the preload in the conditions that the maximum stress of bolt is below its yield limit stress situation.

A new method for evaluating roundness error using polar measurement data, which named as polar mesh searching algorithm (PMSA), has been presented in this paper. The principle of the algorithm was that series of polar-coordinate mesh points were collocated around the periphery of the least square circle according to certain rule, the radius of all the measured points were calculated by regarding each mesh point as the ideal center, and the roundness error from minimum circumscribed circle method, maximum inscribed circle method and minimum zone circle method were achieved accurately through comparing these radius. In the paper, the process and steps using the PMSA to solve the roundness error were described in detail and the mathematical formula and program flowchart were given. The simulation and experiment results show that roundness error can be evaluated effectually and accurately by this algorithm.

A pulsed laser fabrication method is used to prepare fluorescent microstructures on silicon substrates in this paper. A 355 nm nanosecond pulsed laser micromachining system was designed, and the performance was verified and optimized. Fluorescence microscopy was used to analyze the photoluminescence of the microstructures which were formed using the pulsed laser processing technique. Photoluminescence spectra of the microstructure reveal a peak emission around 500 nm, from 370 nm laser irradiation. The light intensity also shows an exponential decay with irradiation time, which is similar to attenuation processes seen in porous silicon. The surface morphology and chemical composition of the microstructure in the fabricated region was also analyzed with multifunction scanning electron microscopy. Spherical particles are produced with diameters around 100 nm. The structure is compared with porous silicon. It is likely that these nanoparticles act as luminescence recombination centers on the silicon surface. The small diameter of the particles modifies the band gap of silicon by quantum confinement effects. Electron-hole pairs recombine and the fluorescence emission shifts into the visible range. The chemical elements of the processed region are also changed during the interaction between laser and silicon. Oxidation and carbonization play an important role in the enhancement of fluorescence emission.

This paper analyses the computation model of preloaded bearing which connects turntable bearing with Flange plate, provides the computation model which connects traditional utation model to the computation of turntable bearing directly. Adopting two ways of preload and service load, this thesis analyzes the maximum loading stress of every single bolt which is connects with turntable bearing. Analyzes and Computes the stress of bolt by utilizing finite element.