Hollow Degree of Hollow Cylindrical Roller Bearing
Hollow Degree of Hollow Cylindrical Roller Bearing
1 Design of hollow cylindrical roller bearings
1.1 Hollow Roller Features
Due to the hollow environment inside the hollow roller, more lubricating oil can be stored to improve the lubrication performance of the bearing; and the hollow roller structure increases the heat dissipation area of the bearing, and the lubricating oil stored in the hollow portion of the roller is in the process of bearing rotation. In the middle, the circulation flow takes away most of the heat generated by the friction when the bearing rotates at a high speed, which effectively reduces the temperature rise of the bearing, avoids the pitting and adhesion of the bearing surface caused by the excessive temperature, and reduces the bearing. Loss of precision.
1.2 Determination of hollow roller parameters
The hollow cylindrical roller bearing is shown in Figure 1. It consists mainly of the bearing inner ring 1, the hollow cylindrical roller 2 and the bearing outer ring 3. The hollow hole in the hollow cylindrical roller body is a single cylinder, and the geometrical dimensions are: cylindrical roller outer diameter d=
11mm, roller effective length L=21mm, journal diameter D 1 =40mm, bearing outer ring diameter D 2 =75.4mm [3]; roller and inner and outer ring materials are made of bearing steel GCr15SiMn, elastic modulus is 216GPa, mooring The loose ratio is 0.3, the mass density is 7820kg/m 3 ; the number of rollers is 16; due to the non-uniform distribution of bearing load surface, a radial load of 20kN is applied at the axis of the rotating shaft, and the equivalent bearing contact surface is affected. Force situation.
2 Study of hollowness
Hollowness is the most important parameter in the overall bearing design. If the hollowness is too small, the intended purpose is not achieved; if the hollowness is too large, the bearing strength of the bearing will be greatly impaired. Therefore, a reasonable choice of hollowness is a key step in the design of this bearing. If the direction of the load applied to the bearing is vertically downward, then when the roller is at the lowermost end, the roller is subjected to the greatest force, so only the case where the hollow roller is at the lowermost end is considered.
Define the hollowness H of the roller to be V 1 /V, where V 1 is the volume of the hollow part of the roller and V is the volume when the roller is not removed. The hollowness of the roller is 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, respectively. The SolidWorks software is used to model the hollow cylindrical roller bearing, and then the Simulation module in the software is used. Perform stress analysis of the hollow roller.
Interpretation of the curve, when the hollowness is below a certain value between 60% and 75%, the maximum equivalent stress increases slowly with the increase of the hollowness of the hollow cylindrical roller bearing; when it is higher than this value, Increase in hollowness, bearing
The maximum equivalent stress rises sharply, so this value is the optimum value of the hollowness. Then, the hollowness is divided into 15 equal parts in the case of 60%-75%, and the same amount of load is loaded.
When the hollowness is lower than 68%, the maximum equivalent stress of the bearing increases slowly with the increase of the hollowness; when the hollowness is higher than
At 68%, the maximum equivalent stress of the bearing increases sharply with the increase of the hollowness. Therefore, when the hollow cylindrical roller bearing hollowness H is 68%, the performance is optimal.
3 Conclusion
Through simulation analysis, the different hollowness H is compared, and the modeling and finite element analysis are carried out from 10%-80%. Finally, the optimum state of the hollowness is 68%, and when the hollowness is lower than 68%, the bearing is the largest. The effect force increases slowly with the increase of the hollowness; when the hollowness is higher than 68%, the maximum equivalent stress of the bearing increases sharply with the increase of the hollowness.