Evaluating the Condition of Sliding Bearings

The assessment of the sliding bearing’s serviceability is primarily determined by the brass bushing. It takes into account the degree of damage, mechanical performance, its role, operating conditions, and the time until the next maintenance schedule of the unidirectional bearing. If certain defects, such as cracks or notches, are identified on any part of the inner ring, outer ring, rolling body, or cage, the sliding bearing can no longer be used and must be replaced.

Why Replace Sliding Bearings?

A myriad of factors can cause damage to sliding bearings, and often it is a combination of these reasons. It may be due to the bearing being subjected to loads exceeding its estimated capacity, ineffective sealing, or inadequate clearance resulting from an overly tight fit in the composite sliding bearing. Each of these causes will leave distinct patterns and trails of damage, facilitating diagnosis. It is generally accepted that a third of the bearing damage results from fatigue, another third from inadequate lubrication, and the remaining from contaminants entering the bearing or improper handling during installation.

Other potential causes for damage can be excessive load (or preloading), high operating speeds, insufficient clearance, intrusion of water or other foreign matter. If these are not the culprits, it’s likely that the accuracy of the shaft and bearing housing is poor or the shaft deflection is significant.

Extending the Service Life of Sliding Bearings

To improve the longevity of sliding bearings, the choice of lubricant and lubrication method is crucial. Choosing the right compound sliding bearing lubricant, its quantity, as well as the correct bearing type can make a significant difference. In addition, it is vital to properly calibrate the fit, bearing clearance, and preloading, and improve the sealing mechanism.

1. Bearing Maintenance: To ensure the bearings remain in optimal condition for as long as possible, regular maintenance and overhauling are necessary to prevent breakdowns, guarantee operational reliability, and enhance productivity and economy. Monitoring operational status, replenishing or changing lubricants, and conducting regular disassembly inspections are integral parts of maintenance.

2. Cleaning of Sliding Bearings: When disassembling the bearing, documenting the bearing’s appearance, verifying the amount of residual lubricant, sampling the used lubricant for inspection, and then washing the bearing is recommended. The cleaning process involves both rough cleaning and fine cleaning, and attention must be paid not to damage the bearing surfaces during this process.

3. Maintenance and Evaluation of Sliding Bearings: Following cleaning, the bearings need to be inspected to determine if they can be reused. This involves examining the state of the raceway surface, rolling surface, and mating surface, the wear of the cage, the increase in unidirectional bearing clearance, and any damage or abnormality unrelated to the decrease in dimensional accuracy.

By providing comprehensive maintenance and consistently monitoring the condition of your sliding bearings, you can ensure their optimal performance and longevity. At Viiplus, we offer the latest and highest quality products to meet your sliding bearing needs. Join our community today and discover the Viiplus difference.

Sliding bearings, often known as plain bearings or bushings, come in a variety of types, each designed to meet specific application requirements. Below are some of the most common types of sliding bearings:

1. Plain Bearings: These are the most straightforward type of sliding bearings. They consist of a bearing surface with no rolling elements and are often used in applications that require high load capacity at lower speeds, where oscillating movements are involved.

2. Flange Bearings: Flange bearings are essentially plain bearings that have a flange on one side. The flange provides axial guidance, which prevents the bearing from slipping out of the assembly.

3. Thrust Bearings: These are specialized sliding bearings designed to handle axial loads. They can be found in applications like automotive transmissions and gearboxes where support for axial loads is required.

4. Linear Bearings: Linear bearings are used in applications where linear motion is required, as opposed to rotational motion. These bearings provide low friction movement along a single axis.

5. Spherical Plain Bearings: These types of bearings feature an inner ring and an outer ring with a spherical sliding surface. They are designed to accommodate misalignment and pivoting motion, making them ideal for articulating joints.

6. Composite Bearings: These bearings are made from a combination of materials, usually a metal-polymer composite. The metal provides strength and rigidity, while the polymer offers a low friction surface.

7. Bi-metal Bearings: These types of bearings consist of two layers: a steel backing for mechanical strength, and a bronze overlay for superior anti-friction characteristics.

8. Hydrodynamic Bearings: Hydrodynamic bearings are a type of sliding bearing where the motion of the parts causes a lubricant (like oil or air) to be pulled into the bearing. This “wedge” of lubricant supports the load and reduces friction.

The selection of the appropriate type of sliding bearing depends largely on the application in question, including factors like load type, load magnitude, operating speed, temperature, and environmental conditions.