Requirements for size control and pre tightening adjustment of cross roller bearings during hot inst
- 2025-03-03
In the assembly process of machine tools, cross roller bearings are usually used as bearings for machine tool turntables. However, during assembly, heating installation methods are often used. Due to the heating temperature and process, it is easy for the bearings to have dimensional deviations, which can affect assembly accuracy. Therefore, it is necessary to control the dimensions during the process. Here, the Ouna editor has compiled the requirements for size control and pre tightening adjustment of cross roller bearings during hot installation for your reference.
Hot installation size control of cross roller bearings
1. Heating before assembly
The outer and inner rings of cross roller bearings are usually interference fit or clearance fit with minimal clearance. Therefore, during installation, oil bath heating or induction heating methods are generally used to heat the relevant components. The heating temperature should not exceed 80 ℃. Generally, the bearing seat ring is heated first, and then the outer ring of the bearing is inserted into the seat ring hole. Then, the installed bearing and seat ring are heated simultaneously to expand the size of the inner ring of the bearing, and then the inner ring of the bearing is installed into the shaft. To use oil bath heating, it is usually necessary to design and manufacture heating oil tanks, heating electric heating tubes, temperature control devices, detection devices, etc. The use of induction heating requires temperature control and demagnetization treatment after heating.
2. Heating size control
Before the formal installation of the cross roller bearing, it is necessary to conduct actual testing on the size changes of the relevant parts after heating to determine whether the size after heating meets the installation requirements, in order to avoid installation failure due to insufficient size changes caused by part heating. The assembly control time for heating the seat ring and bearing, as well as the assembly control time for heating the bearing inner hole component and the shaft, should not exceed 30 minutes to ensure sufficient dimensional expansion during this time.
During the installation and adjustment process of cross roller bearings, an important adjustment task is pre tightening control. Usually, the pre tightening amount is controlled by adjusting the thickness of the gasket, and the torque of the rotary worktable is detected to verify the degree of pre tightening. When measuring torque, use a spring tension meter to measure the uniform tension of rotation, and at the same time measure the length of the force arm to calculate the torque.
When pre tightening the cross roller bearing, the torque consistency of each bolt should be controlled, and the tightening torque used should diagonally tighten the bolts 2-3 times. Afterwards, the cross roller bearings can be installed in the workbench system for trial cutting of the entire machine, and the roughness of the workpiece can be tested to reflect whether the bearings are preloaded. If necessary, the preloading of the bearings can be adjusted again until satisfactory roughness and usability are achieved.
The above is the size control and pre tightening adjustment requirements for cross roller bearings that the Ouna editor has compiled for everyone. We hope it can be helpful to everyone. The hot fitting size control of bearings is actually not the same as that of cross roller bearings. For bearings with high precision requirements for installation and use after installation, the hot fitting size accuracy has strict control requirements. We hope everyone can pay more attention to it during assembly. As a cross roller bearing manufacturer specializing in research and development, manufacturing, and sales, Luoyang Ouna Bearing Co., Ltd. can provide various series of high-precision bearing products. If you need, you can leave a message on our website or call customer service for detailed consultation.