Bearings and Their Resistance to Friction
Built as a rolling mechanical assembly, bearings facilitate different types of load, thrust, and radial movement between moving parts along a track. Constructed in multiple forms to support various applications, bearings are used to constrain relative motion along a track while ensuring a desired motion is achieved. This dramatically reduces friction between all moving parts, providing high rotational speeds for rotating or oscillating machinery. Operating off of their own unique set of principles, common bearing types include: plain bearings, rolling element bearings (i.e., ball bearings, roller bearings), jewel bearings, fluid bearings, magnetic bearings, flexure bearings, and more.
Necessary for promoting rolling motion along a track, rolling element bearings are a cost-effective solution which help to promote minimal part degradation over time by mitigating friction between parts in a system. Rather than moving in a sliding motion, an action which can generate unwanted friction, balls or rollers are placed along two tracks, rings, or races. The structure of a rolling element bearing acts to minimize rolling and sliding resistance; therefore, rolling element bearings improve a system’s efficiency and power output for rotating or oscillating machinery.
are the most common type of rolling element bearing, but are often only used for smaller radial or thrust applications. Limiting contact with each ball and their connection to a track, an overloading of balls can lead to overcrowding, ultimately increasing the risk of part deformation and instability.
Often used as a step-up solution to ball bearings, roller bearings
are manufactured to withstand high axial and radial load capacities. Similar in use to a conveyor belt, roller bearings implement cylinders along a track or race — unlike the balls from a ball bearing. Providing an increased surface area between all rollers and bearing parts, roller bearings should only be employed for applications that require distributing a load over a larger area. Additionally, roller bearings should not be used when thrust support is needed as they are not designed for such applications.
Needle Roller Bearings
Providing necessary stiffness while coming in a compact design, needle roller thrust bearings are an economical solution for those who are looking for a bearing that is available in a diverse set of sizes, tolerances, and applications. Similar to roller bearings, needle roller bearings
function with small cylindrical rollers
to evenly distribute a load. Though, unlike standard roller bearings, needle roller bearings are meant to support radial loads and rotational speeds, alondsige a combination of various other attributes such as thrust. As such, needle roller bearings can be found in the following types: drawn cup, precision race, caged roller, and thrust roller. Often used for industrial or automotive transmission systems, needle roller bearings can also be used for gearboxes, two or four stroke engines, air compressors, and more.
Primarily manufactured to support axial loads, thrust bearings
are not recommended for any system requiring high speeds. Capable of supporting up to two axial loads rotating in opposite directions, thrust bearings can often also be applied to accommodate radial loads if necessary.
Posted on September 28, 2021