Designing to Lower Cost – Selecting the Right Bearing
The majority of applications can be effectively handled using a “standard bearing.” A “standard bearing”, in this case, refers to a ball bearing that is in such worldwide demand that large volumes are produced. This virtually guarantees continuity of supply while assuring pricing benefits for the customer. The selection of a “standard bearing” at the design stage cannot be overemphasized. The considerations necessary to design for lower cost include:
Cage style (retainer)
Assembly and fits
Although different designers may vary in their approach to bearing selection, the following is one method that works well.
Establish operating, environmental and performance requirements such as load, speed noise, etc.
Select a bearing configuration to meet the above requirements.
Some examples of configuration types are:
Flanged or unflanged
With or without a snap ring
Determine bearing envelope to accommodate shaft and housing requirements. This step is critical to cost. It is quite often more cost-effective to design the housing and shaft around a popular bearing size than vice versa.
Specify enclosures as necessary. Be careful not to specify a more expensive enclosure than necessary to perform properly in the application.
Specify the required cage type. For the majority of cases, the standard cage for a particular chassis size will be adequate.
Determine the bearing noise rating that is required for the application. In most cases, our stand “No Code” noise rating will provide quieter bearing operation than most other components in the system. For extremely noise-sensitive applications, a quieter noise rating can be specified.
Determine the degree of precision needed for the ball bearings to achieve the performance requirements (ABEC Level). Do not overestimate what is truly necessary to achieve the desired performance.
Determine the radial play specification of the ball bearings. The standard radial play specification for a chassis size will be adequate to handle normal press fits, moderate temperature differentials, and normal speeds.
Determine bearing lubrication requirements. This should include lubrication characteristics and the amount of lubricant needed for the bearing. This is a critical step in the performance and reliability of the bearing in the application.
Care should be taken throughout the design process with respect to both cost and performance. The key to designing for the lowest total cost is to involve the sales and application engineering staff early in the selection process. Ball-bearing costs will be impacted greatly if the envelope dimensions are not given consideration at the time of bearing selection. Application engineers are there to help you in the design and selection process of the ball bearing, ensuring your success.