Getting the best ball bearings involves asking and answering a series of questions. This Q&A from Schatz Bearing, a leading provider of precision ball bearings, can get you started.
What is the application?
The best ball bearings are used in applications ranging from aerospace, space, and defense to medical and semiconductor equipment. There are many different types of bearings, and the type of product that’s used with a ceiling fan doesn’t have the same degree of precision as a bearing used in a jet engine.
What is the speed at which the bearings will operate?
Bearing speed is typically measured in revolutions per minute (RPM). If your application exceeds the RPMs for which a bearing is rated, excessive heat from friction could result in premature wear or failure. For bearings with contact seals, the limiting speed usually determines their maximum operational capacity.
Do you need bearings for full rotation or oscillation?
Oscillating bearings wear differently than rotational bearings. That’s because their repeated back-and-forth movements can evacuate the grease in raceways. In high-speed applications, lubrication is especially important to avoid metal-to-metal contact.
What are the loading conditions?
Ball bearing loading conditions include radial, axial (thrust), and moment loads. Radial loads are perpendicular to the axis of the shaft, parallel to the bearing’s radius. Axial loads or thrust loads act parallel to the axis of the shaft. Moment loads attempt to rotate bearing rings perpendicular to the rotational axis.
What is the bearing configuration?
A bearing configuration, or arrangement, supports and locates a shaft relative to other components, such as housings. There are many configurations that can be used in a given application, such as radial, single-row, double-row, self-aligning, and angular contact bearings.
Angular contact bearings can be arranged to operate as pairs. There are four main angular contact bearing configurations: face-to-face or double-face(DF), back-to-back or double-back (DB), tandem or duplex tandem (DT), and universal.
What is the bearing material?
Ball bearing material options include SAE 52100, 440C, and 440C modified steel. EMS138 stainless steel offers very good corrosion resistance and excellent wear resistance. M50 is an aerospace bearing material with excellent fatigue resistance. Hybrid bearings with steel rings and ceramic balls are also available.
What is the operating environment?
The operating environment includes both the ambient temperature and the range of operating temperatures, or service temperatures. It’s also worth considering whether the environment is clean or dirty since the presence of dust or particulate matter could affect bearing lubrication.
What is the life expectancy?
Bearing life expectancy is the amount of time that a ball bearing can be expected to perform as required under pre-determined operating conditions. Primarily, it’s based on the number of rotations a bearing can complete before it begins to show spalling, stress cracking, or other symptoms of fatigue.
What is the estimated annual usage?
Estimated annual usage (EAU) refers to the number of bearings that you plan to buy in a year. Bearing manufacturers ask for this information so that they can plan their production schedules, inventory levels, and budgets.
How long will the program last?
Program life is related to EAU, but typically lasts for multiple years. With aerospace and defense projects, program life extensions may require bearings to be available for decades. For example, the F-16 was introduced in the 1970s but will remain in service until 2050 because of a program life extension.
When is bearing hardware needed?
Bearing hardware includes the cages that are used to hold rolling elements in the proper orientation so that they remain separated and follow the correct rolling path. If your application needs bearing hardware, remember to consider the potential effects of vibration, friction, and contamination.
Has a target price been established?
A ball bearing’s target price is a function of target costing, a strategy to set the price point for a product and then engineer it to that point. To avoid cost overruns, it’s important to account for all of your costs, including transportation and storage.
Who are the typical bearing suppliers?
The suppliers for a ball bearing can vary by degree of precision, industries served, and geographic location. For example, if you’re looking for a Made in America bearing that meets Boeing or MIL-SPEC standards, you won’t find it by searching overseas for low-cost, low-precision products.
Are there any pain points in the bearing supply chain?
The best ball bearing suppliers minimize supply chain risks by keeping sufficient quantities of materials in stock and maintaining their ability to scale up production in response to rising demand. If you’re ready to work with the best ball bearing supplier for precision products, contact Schatz
