Selecting Bearing Vibration Group
Introduction
The selection of the bearing vibration group is obviously a difficult and complicated task. Establishing the appropriate vibration group based on the specific application requirements is essential for the service life and performance of the bearing. This undertaking involves multiple steps, from choosing the correct bearing type, verifying load and speed conditions, determining required clearance and preload, to selecting a calcium soap based grease and seal type. This paper proposes an approach to select the most suitable bearing vibration group for a specific application.
Selecting the Bearing Type
The first step in selecting the bearing vibration group is to choose the applicable bearing type. The selection of the bearing type is based on the nature of the application environment, such as the operating temperature, the rotational speed, the spatial parameters, the load direction and magnitude, etc. The available bearing types can be divided into three categories:
• Radial Bearings: Radial bearings are bearings that are intended to support axial loads and are suitable for operation under medium and high speeds. This type of bearing is typically used in engines, pumps and gearboxes.
• Thrust Bearings: Thrust bearings are intended to support both axial and radial loads and are suitable for low and medium sized speed applications. This type of bearing is typically used in conveyors and rotating machines.
• Mixed Bearings: Mixed bearings combine the advantages of radial and thrust bearings and can be used for a wide range of applications. These bearings can carry both radial and axial loads and are suitable for medium and high speed operations.
Verifying Load and Speed Conditions
Once the bearing type has been selected, the next step is to verify the load and speed conditions. These parameters are essential for understanding the force that the selected bearing must be able to bear. In general, radial bearings are capable of handling higher speed loads, whereas thrust bearings can handle higher static load. If the speed and load conditions of the application are not appropriate for the selected bearing type, a different bearing type must be chosen.
Determining Required Clearance and Preload
Another important factor in establishing the appropriate bearing vibration group is determining the required clearance and preload. The clearance is the difference between the outer diameter of the inner ring and the bore of the housing. The preload is the force created by the axial components of the bearing loading. Depending on the application, it is possible to have either low, medium or high preload in order to decrease the vibration levels. If a preload is added, it is necessary to ensure that the possibility of damaging the bearing is decreased.
Selecting a Grease and Seal Type
Once the bearing type and the load and speed conditions are determined, the next step is to choose the appropriate grease and seal type. Depending on the application type, different types of grease and seal can be chosen. For general purpose applications, a calcium soap based grease is usually recommended. However, for high temperature and high speed applications, synthetic oils and lip seal types may be more suitable.
Conclusion
The selection process of the bearing vibration group is highly complex and requires careful consideration of multiple parameters. This article has proposed an approach to select the most suitable bearing type, verifying the load and speed conditions, determining required clearance and preload, and selecting a calcium soap based grease and seal type for a specific application. By taking these steps carefully, engineers can ensure that the bearings are at the optimum performance and remain serviceable for a longer duration.
