By Joyce Laird, Contributing Editor
What makes flanged ball bearings different than other ball bearings?
A flanged ball bearing is not truly a different type of bearing. Just as ball bearings are offered sealed or open, they are also available flanged or plain. The flange is just another option given to the design engineer by the bearing manufacturer. A flange is an extension, or a lip, on the outer ring of the bearing, designed to aid the mounting and positioning of a bearing in a delicate or problematic application.
Why are these types of bearings needed?
Dave Nufer, Sales Engineer – Turbo, Specialty and Ball Bearings for NMB Technologies Corporation, explains, “Flanged bearings are most commonly used when the application requires the bearing to be locked in place. The design engineer will want to lock the bearing axially, along the shaft, or perpendicular to the shaft, radially, depending on his application. A flanged bearing is used in this instance to help withstand axial thrusting. If there is any axial load or axial push on the bearing, the flange will prevent the bearing from moving axially.”
What applications benfit from these types of ball bearings?
Any application that will require a bearing to be mounted in a high vibration area, as well as any application that requires high axial loads, will benefit from using a flanged bearing. “Automotive applications are a good example; all vehicle components must be able to withstand high vibrations.”
The design engineer needs to be able to select and assemble a bearing that will withstand vibrations, as well as high temperatures. Therefore, adhesive or interference fit in the assembly of a bearing into an automotive application is often insufficient. In order to insure long life and durability of the bearing the selection comes down to a flanged bearing. A flanged bearing will maintain its position and will survive the hostile environment and vibration within the vehicle. If necessary, assembly of a flanged bearing can also include a secondary attachment, like a retaining clip.”
He adds that very high temperatures will also require the selection of a flanged bearing. Under the hood applications, where temperatures are often around 180°C and the presence of materials such as those between a ball bearing and a housing or shaft, will create a different rate of thermal expansion.
“For example, a steel bearing is pressed into aluminum housing; the housing may expand earlier than the steel bearing thus losing the interference with the bearing. The use of a flanged bearing in this application will hold the bearing in place–axially–regardless of the imbalance in expansion rate.”
Flanged bearings are most commonly used in light duty applications, such as food processing machinery, conveyors, material handling, belt drives in HVAC, textile, baggage systems, medical processing and various other light duty industrial applications.
How are these bearings installed?
Once the decision has been made that a flanged bearing is necessary for the application, then the installation of the bearing is not complicated. The drawback is that many types of flanges are expensive to manufacture, and will increase the cost of the application design.
In closing, Nufer says that it’s rare to encounter an application where a flanged miniature ball bearing is required. “It is important for the design engineer to discuss all application alternatives with their bearing supplier because there is a cost increase by selecting a flanged bearing. The design engineer needs to make sure that he is not over designing the application in relation to the need for a flanged bearing. He may find that there are often less expensive options available for bearing control. However, for some applications, flanged bearings are the only good alternative. Therefore, definitely talk to an expert to be sure before making a final decision.”