How to Choose Heavy-duty Bearings

The bearing is an important part of contemporary machinery and equipment. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement, and ensure its rotation accuracy. The bearings we often talk about include spherical plain bearings, rod end joint bearing, etc.

 

When choose different bearings, we need to pay attention to different parts. For example, when choosing rod end joint bearings, we need to consider rod ends. So what do we need to consider when choosing a heavy-duty bearing?

 

1. The main points of choosing heavy-duty bearing are basically the same as those of high-rigidity bearings.

The application of heavy-duty bearings must be considered in conjunction with the working characteristics of heavy-duty bearings. Heavy-duty bearings are often in a state of high stress during operation, and the bearings are sensitive to high stresses. Therefore, the application technology should strive to reduce the stress of the bearings, and the reduction of stress is very beneficial to extend the life of the bearings. For example, under the condition that the axial position allows, the high-load machine doubles the original single bearing of a certain fulcrum to two to bear the radial load, and despite the effect of uneven load, under the same workpiece conditions, the service life of the two bearings of the fulcrum can be increased by more than 2 times compared with the original single bearing. In fact, heavy machinery often uses multiple bearings or multiple rows of bearings at a fulcrum to bear radial loads.

 

 

2. Coordination, clearance and lubrication of heavy-duty bearings

The coordination, clearance and lubrication of heavy-duty bearings must be considered uniformly. In order to reduce the stress of heavy-duty bearings, it is desirable that the lubricating film layer is thick, so it is preferred to use a higher viscosity lubricating oil or a grease with a higher viscosity oil as the base oil, and at the same time, we hope that under the conditions of ensuring good lubrication, the friction torque due to the viscosity of the lubricant should not be too high.

 

The interference fit of the heavy-duty bearing rotating ring is larger than normal bearings, and this has an adverse effect on the deformation of the raceway and the service life of the bearing. Therefore, if possible, it is desirable to reduce the interference amount appropriately, which requires reducing the toughness of the mating surface. At the same time, keep the lubrication normal, because in the event of lubrication failure, the excessive friction torque on the surface of the raceway under heavy load strengthens the creeping trend of the mating surface, and even slips. Although most of these phenomena occur in the outer ring, but in serious cases, the inner ring is inevitable. It should be noted that the actual fit of the outer ring should not be too large, so as to prevent grease from infiltrating into the surface.

 

Only after carefully taking effective countermeasures, it is allowed to appropriately reduce the interference of heavy-duty bearings. Although the interference is slightly reduced, the improvement of the bearing stress state is greater. Of course, the benefit of thickening the oil film is greater. Due to the large contact area of the rolling surface of the bearing under heavy load, the fit is tight, and the deformation of the bearing ring is large, so the clearance of the bearing is usually also large.

 

 

3. Improve bearing use conditions from the design of the main engine.

All the transmission shafts in the transmission chain of the main engine should be properly taken at a higher speed until they are reduced to the working speed. The mounting components left for the spindle bearing should also be larger, which makes it easier to choose larger bearings, which are beneficial to the bearings.