How to solve the problem that the guide bearing temperature of CNC lathe is too high

The guide bearing temperature of CNC lathe is too high, which is a common failure problem. Here’s how to deal with high temperature problems in CNC lathe bearings.

1. The function of guide bearing

The purpose of setting up CNC lathe guide rail bearings is to limit the work of the generator spindle so that it can only bear the radial load on the generator spindle within the clearance range of the guide rail bearings.

2. Working principle of guide bearing

The working principle of the thin oil lubricated block bearing is that when the unit rotates at high speed, the lubricating oil enters the joint surface of the bearing bush and the journal to lubricate the Tin Bronze Motor Spherical Oil Bearing bush. After being cooled by the oil cooler, the lubricating hot oil enters the bearing bush and journal again. joint surface. As the unit operates, the lubricating oil is automatically cooled through reciprocating circulation. When the main shaft rotates, a stable oil wedge is formed between the journal and the bushing surface, which bears the radial load and transfers it to the guide bearing seat and then to the frame.

3. Composition of guide bearing

CNC lathe guide bearing is a thin oil lubricated block bearing, which is mainly composed of bearing cover, lubricating oil tank, cooler, oil return pipe, bearing sleeve, bearing seat, load screw, thermometer, etc. The guide bushes of the two units at station B are divided into eight guide bushes, which are evenly distributed on the generator main shaft guide journal according to the circumference.

4. Analysis of the causes of increased bearing temperature and unit vibration

Through operation observation and maintenance analysis, it is believed that there are two main reasons for the increase in bearing temperature and vibration of the unit:

The main results are as follows: The increase in bearing clearance is much greater than the clearance required by the design, which makes it difficult for lubricating oil to form an oil wedge when entering the bearing tile surface, resulting in poor lubrication, causing the temperature of the guide bearing to increase and the vibration of the unit to increase;
The contact points on the 2-axis tile surface are small and Laser Cutting And Bending UAV Body Shell is insufficient, which does not meet the equipment specifications.

5. Solution to guide bearing temperature rise

According to the manufacturer’s design requirements, when the CNC lathe is running continuously, the maximum temperature of the cooling water should not exceed 25°C, and the maximum temperature of the ceramic tile temperature and oil temperature should not exceed 65°C. Changes in wattage and oil temperature are not only related to the temperature of the cooling water, but also to the circulation of lubricating oil and the clearance between the spindle shaft and journal.

The allowable clearance of CNC lathe guide Powder Metallurgy Sector Gear is 0.2~0.3 mm (two-way clearance), and the lower part of the bearing is immersed in lubricating oil. When the spindle rotates clockwise, lubricating oil can easily enter the bearing surface of the guide bearing and create an oil wedge. When lubricating the surface of ceramic tiles, even through the large swing point of the spindle, although the matching gap is small, due to the short distance, good lubrication conditions, less heat generated by friction, and good cooling effect, generally it will not cause the bearing temperature rise phenomenon, nor will it cause Tile burning.