How to optimise the rotational accuracy of crossed roller bearings?|Shandong XingMao Bearings Co., Ltd.

How to optimise the rotational accuracy of crossed roller bearings?

Crossed roller bearings are widely used in mechanical transmission, robot joints, aerospace and other fields due to their high precision, high rigidity and compact structure. However, with the increase of use time or changes in operating conditions, the rotational accuracy of crossed roller bearings may gradually decline, affecting the normal operation of equipment. Therefore, it is important to understand the causes of accuracy degradation and take optimisation measures to extend bearing life and improve equipment performance. This article will give you a detailed introduction on how to optimise the rotational accuracy of crossed roller bearings.

How to optimise the rotational accuracy of crossed roller bearings
First. Material selection and optimisation
1. High-performance materials
Material properties: selecting materials with high strength, high hardness, high wear resistance and high corrosion resistance can improve the wear resistance and service life of crossed roller bearings. For example, the use of chromium-molybdenum alloy steel or high-carbon chromium steel can improve the strength and wear resistance of the bearing, while ceramic materials have higher hardness and corrosion resistance.
Material applications: In high-load, high-temperature or corrosive environments, the use of high-performance materials can improve the rotational accuracy and stability of crossed roller bearings. For example, in the aerospace field, ceramic materials are often used to manufacture bearings to meet the requirements of high precision and high reliability.

Second, structural improvement and optimisation
1. Increase the number of rollers
Optimisation method: By optimising the internal structure of the bearing and increasing the number of rollers, the load carrying capacity and rigidity of the crossed roller bearing can be improved. More rollers can better disperse the load and reduce the stress of individual rollers, thus improving the precision of the bearing.
Optimisation strategy: At the design stage, the arrangement and size of the rollers are optimised through finite element analysis to ensure that the overall performance of the bearing is not affected by increasing the number of rollers. For example, multi-row roller design can be used to improve the rigidity and bearing capacity of the bearing.
2. Optimise roller shape
Optimisation method: The use of optimised roller shapes, such as elliptical rollers or hyperbolic rollers, can better spread the load and improve the rigidity of crossed roller bearings. Optimised roller shape can reduce contact stress and improve the running accuracy of the bearing.
Optimisation strategy: determine the roller shape and size parameters through computer simulation and experimental verification. During processing, the manufacturing accuracy of the rollers is strictly controlled to ensure that their shape meets the design requirements. For example, use high-precision grinding process to manufacture the roller to ensure its surface finish and dimensional accuracy.
3. Increase the strength of the cage
Optimisation method: use high-strength materials to manufacture the cage, such as high-strength steel or high-performance plastics, and optimise the structural design of the cage. The strength of the cage directly affects the running accuracy and reliability of the crossed roller bearings.

Optimisation strategy: Optimise the structure of the cage through finite element analysis to ensure its stability and reliability under high load conditions. In the processing process, the manufacturing accuracy of the cage is strictly controlled to avoid the strength degradation caused by manufacturing defects. For example, the plastic cage is manufactured by injection moulding process to ensure its dimensional accuracy and surface quality.

Third, the optimisation of the lubrication system
1. Selection of suitable lubricant
Lubricant selection: according to the specific working conditions of the bearing to select the appropriate lubricant, such as high-quality grease or lubricant, can reduce the friction and wear of the crossed roller bearings. Lubricant selection should consider the operating temperature, speed and load conditions of the bearing.
Lubrication method: Optimising lubrication methods, such as micro-lubrication and the application of self-lubricating materials, can further improve the performance of bearings. For example, the use of micro-lubrication system can control the supply of lubricant, reduce the waste of lubricant and improve the lubrication effect.
2. Regular maintenance of the lubrication system
Maintenance measures: Regularly check the operating status of the lubrication system to ensure that the supply of lubricant is sufficient and uniform. Clean the impurities in the lubrication system to ensure smooth lubrication channels. For example, replace the lubricant regularly, clean the oil and impurities in the lubrication system to ensure the normal operation of the lubrication system.
Note: The replacement cycle of lubricant should be determined according to the actual operation of the equipment to avoid bearing wear due to lubricant deterioration. For example, for high load or high temperature operation of the cross roller bearings, the lubricant replacement cycle should be shortened to ensure the lubrication effect.

Fourth, the adjustment of preload
1. Importance of preload
Preload function: appropriate preload can eliminate the internal clearance of the bearing, improve the stiffness and precision of the bearing, reduce deflection and improve positioning accuracy. Adjustment of preload force is especially important for high precision applications.
Adjustment method: By accurately adjusting the preload, the deflection and vibration of the bearing can be reduced and its running accuracy can be improved. Adjustment of preload should be customised according to specific application requirements to ensure that the bearing maintains its ideal condition during operation.
2. Adjustment method of preload force
Adjustment tools: Use high-precision torque spanners and micrometers to ensure the adjustment precision of preload force. For example, the tightening torque of the nut is controlled by a torque spanner to ensure that the preload force is within the design range.
Caution: The adjustment of the preload force should be customised according to the specific application requirements to avoid damage to the bearings due to too much or too little preload force. For example, for high-precision robot joint applications, the preload force should be adjusted to the ideal state to ensure the positioning accuracy and operational stability of the joint.

fifthly. Improvement of assembly accuracy
1. Preparation before assembly
Cleaning parts: Before assembly, clean the bearings and mounting parts with detergent and a soft cloth to ensure that their surfaces are free of oil and impurities. Cleaning can reduce pollution during assembly and improve assembly accuracy.
Marking parts: Make clear marks on the corresponding surfaces of the shaft and housing, near the assembly chamfer on both sides, indicating the peak deviation and direction. Marking can help to locate and adjust the parts quickly during the assembly process.
2. Tips in the assembly process
Uniform application of force: In the installation process, the force should be applied uniformly to avoid local overloading of the crossed roller bearings. For example, use a mounting sleeve or press to gently tap the bearing to ensure that it fits tightly with the shaft and housing.
Gradual adjustment: Gradually adjust the clearance and position of the bearing to ensure its mounting accuracy. For example, gradually adjust the preload of the bearing by tightening the nut step by step to ensure that it is within the design range.
3. Inspection after assembly
Checking the mounting accuracy: After the mounting is completed, use high-precision measuring tools, such as micrometers and gauges, to check the radial and axial clearances of the crossed roller bearings to ensure that they are within the design range. For example, measure the radial clearance of the bearings by micrometer to ensure that it meets the design requirements.
Checking the operating condition: Rotate the bearing manually to check its operating condition and ensure that it can rotate freely without abnormal noise or vibration. For example, check the running sound of crossed roller bearings through a stethoscope to ensure that they run smoothly.

How to optimise the rotational accuracy of crossed roller bearings? It is the need to comprehensively consider a number of aspects such as material selection, structural improvement, lubrication optimisation, preload adjustment and assembly accuracy improvement. Through scientific optimisation strategies and technical improvements, the rotational accuracy of crossed roller bearings can be improved, their service life can be extended, and the operational efficiency and reliability of equipment can be enhanced. In practice, enterprises should make adjustments according to the specific situation, regularly check and maintain the equipment to ensure the long-term stable operation of the equipment.

We hope that the detailed analysis and optimisation methods in this article can help you to correctly optimise the rotational accuracy of crossed roller bearings and guarantee the normal operation of equipment.