High temperature bearings

What is High Temperature Bearing ？

The so-called high-temperature bearing refers to the working temperature is higher than the temperature of the ordinary bearing, and the bearing used at a general working temperature of more than 150 ° is called a high-temperature bearing.

 

Characteristics of high temperature bearings:

 

1. Lifetime lubrication, no grease is added during use.

 

2. Cost-effective, the quality is dozens of times higher than that of ordinary bearings.

 

3. It has won the trust of our customers with a long service life.

 

4. High-temperature bearings are widely used in metallurgy, kilns, glass, blast furnaces, painting equipment and other machinery under high temperature operations.

 

High-temperature bearings are mainly used in aviation jet engines, gas turbines, nuclear reactor systems, X-ray tube tungsten discs, high-speed vehicles, rockets, and spacecraft.

 

Mounting of high-temperature bearings

In addition, if pressure is applied to one side of the ring (such as the outer ring), and the other side of the ring (such as the inner ring) is pressed into it through the rolling element, this will often cause indentation or abrasion on the rolling surface, and it must not be used, especially if the non-separable bearing is installed on the shaft and bearing housing at the same time.

 

In the process of heating and installing the bearing, it is necessary to understand the temperature range of the high-temperature bearing under different high-temperature bearings.

 

Fit of high-temperature bearings

1. Interference

 

The inner ring and outer ring of the rolling element are fixed on the shaft or bearing box, and when it is loaded, the ring and the shaft or bearing box do not have radial, axial and rotational relative movements, and this relative motion will cause friction, friction corrosion or friction cracks on the mating surface, so as to cause damage to the bearing, shaft and bearing box, and then the abrasion powder is mixed into the bearing, which becomes the cause of poor operation, abnormal heating or vibration.

 

As for the fixed bearing method, it is best to leave an interference amount on the mating surface of the ring and the shaft or bearing housing, and the static fit is optimal, so that the load of the thin-walled ring is evenly distributed on the circumference without affecting the load capacity of the bearing.

 

However, in addition to the inconvenience of attaching and dismounting the bearing, it cannot be used in all cases when the bearing is separated and cannot be moved axially when the bearing is separated when the bearing is used.

 

2. The choice of fit

 

The choice of fit is generally carried out according to the following principles:

 

(1) According to the direction and nature of the load acting on the bearing and which side of the inner and outer rings rotates, the load borne by each ring can be divided into rotary load, static load, or non-directional load, the ring that bears the rotating load and the non-directional load should take the static fit (interference fit), the ring that bears the static load can take the transition fit or dynamic fit (clearance fit), when the bearing load is large or bears vibration and shock load, the interference must be increased, when the hollow shaft, thin-walled bearing box or light alloy and plastic bearing box are used, It is also necessary to increase the amount of interference.

 

(2) When it is required to maintain high rotation accuracy, high-precision bearings must be used, and the dimensional accuracy of shafts and bearing boxes must be improved, so as to avoid excessive interference, if the interference is too large, the geometric accuracy of the bearing or axle box can affect the geometry of the bearing ring, thereby damaging the rotation accuracy of the bearing, if the inner and outer rings of non-separating bearings (such as deep groove ball bearings) are static fit, then the bearing installation and disassembly are extremely inconvenient, and it is best to adopt a dynamic fit on one side of the outer ring.

 

3. Cooperate is recommended

 

Regarding the shaft diameter and bore size tolerances of the shaft and bearing housing where the bearings are mounted, ISO283 (dimensional tolerances and fits) has been adopted in the metric series, so the fit tolerances have been determined according to the selected shaft diameter and bore size tolerances.