AS9120B, ISO 9001:2015, and FAA AC 0056B Accredited

A Guide to Flange Bearings and How They Work

Bearings are hardware components found in a wide variety of settings and assemblies, generally performing the roles of facilitating motion, constraining movement, and reducing friction that occurs between moving parts. To accommodate diverse needs where factors such as loads, surface types, and other variations may exist, a number of bearings have been designed over the years. One common form of bearing is the flange bearing, a hardware component that is mounted within a cast iron flange.

Flange bearings can be further classified based on the flange style they present, the general types being four-bolt, three-bolt, and two-bolt flanges that are square, tri-cornered, or diamond-shaped respectively. Each subtype may also be further varied based on the bearing style as well, with ball, plain, needle roller, and roller bearings all being typical. Lastly, other ways in which flange bearings may differ is by the materials that are used for construction. While many are made from metals like bronze, plastic bearings are also a potential option.

Regardless of type, most flange bearing components are used to support a shaft that is perpendicular to the mounting surface of the bearing. This is important, as shafts have the potential of causing a variety of shaft flex, vibration, or axial load issues that source from high speeds or heavy loads. With a flange bearing, the shaft can be supported through load distribution, and the number of bearings needed will often come down to the length and rotational speed of the shaft. When choosing between flange bearing options, some important factors to keep in mind include cost, radial force levels, assembly space restrictions, and more.

When it comes to the installation process for flange bearing components, everything tends to be conducted at the shaft’s outer end to better guarantee smooth, low-friction rotary movement. With a plain bearing or bushing, the linear movement of a shaft can provide a smooth and flat surface that promotes increased control, and an oil-impregnated bushing can ensure a long service life without the need for frequent oiling or greasing. For the material of the bushing, bronze and nylon are the most common.

In applications where assemblies need support against radial loads while maintaining a low-profile design, flange-mounted, needle-type roller bearings are a good option. The flange present on these types of bearings may require the application or grease, though others are maintenance-free as they can remain operational without the need for continual application.

With a roller bearing flange, one can establish radial load support while also deterring any linear movement of the shaft. As compared to other options, the roller bearing flange offers the highest degree of load support. While this is very advantageous for a number of applications, it does come at the cost of higher price points for such hardware components.

If you are interested in procuring flange bearing components for your operational needs, look no further than Aviation Sphere and our unrivaled inventory of items. Owned and operated by ASAP Semiconductor, we offer customers access to an expansive inventory that contains a plethora of top-quality items tracing back to leading manufactures that we trust. With our easily navigable catalog right at your fingertips, we encourage you to take the time to explore our offerings at your own leisure.

Once you find items of interest, be sure to request a quote for your comparisons at your earliest convenience. Upon our review of your submission, a member of our staff will reach out to you in 15 minutes or less to continue the purchasing process. If you would like to directly reach out to our team to discuss your needs, we are always happy to take your call or answer any emails you send our way. Get started today and see how we can operate as your strategic sourcing partner for all your operational needs!


Recent Twitter Posts

Semiconductor's Certifications and Memberships
The only independent
distributor with a
  • All Orders are Fulfilled in the U.S.A
  • All shipments must comply with U.S.A export laws.
  • No exceptions.

“We Proudly Support Intrepid Fallen Heroes Fund that serves United States Military Personal experiencing the Invisible Wounds of War : Traumatic Brain Injury (TBI) and Post Traumatic Stress (PTS). Please visit website ( and help in their valiant effort”.

Thank You for Visiting.

We Hope that You Will Visit Us Again the Next Time You Need NSN Parts and Make Us Your Strategic Purchasing Partner.

Request for Quote

We use cookies to ensure that we give you an amazing experience on our website. If you continue to use this site we will assume that you are happy with it.