AS9120B, ISO 9001:2015, AND FAA AC 0056B ACCREDITED

Needle Roller Bearings and Their Functionality

Bearings are popular hardware elements that are found in a wide variety of applications, serving to facilitate and constrain the motion of moving parts in an assembly while mitigating friction. To meet the diverse needs of various assemblies, there are numerous types of bearings that have come about, each differing in design, load bearing capacity, etc. The needle roller bearing is a specialized type, notable for its long, cylindrical rollers that have a length that is four times the size of the diameter. While differing from typical roller elements, the design of the needle roller bearing and its races allows the component to excel in numerous applications, such as within automobiles. To help you better understand the use of the needle roller bearing, we will provide a brief overview of its design, functionality, and applications.

As the smallest and lightest option within the roller bearing family, needle roller bearings are quite useful for applications where weight and space is a concern. When compared to single-row ball bearings and roller bearings that have a similar outer diameter, there are certain advantages of the needle roller bearing in particular. For example, needle roller bearings exhibit higher load capacities, and they can take on larger, more rigid shafts when placed in an assembly. They also exhibit optimal rolling characteristics within a small cross section, and their lower price point makes them very useful when cost is a concern.

For those who want the most economically feasible option, the best bearing to use is one with a full-complement of loose needle rollers that are placed between a shaft and housing. For axial location to be established, hardened end washers are used. Generally, this form of needle roller bearing is popularly found in environments where the bearing outer ring is a hardened and grounded gear bore. Nevertheless, there are needle rollers with a wide variety of end configurations, ensuring that operators can have a solution for misalignment, deflection, stress distribution, and more.

Drawn-cup needle roller bearings are another common option, and they are best when an ease of handling and installation is desired. These options can perform as loose rollers in a unitized assembly. For the outer raceway or shell, low-carbon strip steel is used and case hardened. As there is no need for further machining, the drawn-cup needle roller bearing is another economical option.

When one uses a full-complement drawn-cup needle bearing, they can achieve load ratings that meet or surpass ball and roller bearings with a comparable outer diameter. With thin cross sections, drawn-cup needle roller bearings are provided with enhanced shaft diameters that they can operate directly on. As the loaded rollers create many contact lines, the bearing is optimal for static, oscillating, and slow rotating operations. Caged options are fairly similar to the full-complement type, albeit lacking some load capacity. Despite this, they are better suited for high speed and shaft misalignment applications as well as load deflection.

While caged assemblies are not always used, they are beneficial when one wants to ensure high load distribution between raceways and rollers. Additionally, cages also promote better capability for high-speed operations and bolster tolerance to load deflection and shaft misalignment. Generally, caged needle roller bearings are most suitable for planetary gears, idler gears, constant-mesh gears, and connecting rods.

For heavy-duty assemblies such as heavy machinery, hydraulic pumps, and automobile steering gears, a heavy-duty needle roller bearing will be needed. These options exhibit a ground outer ring that is machined and thick, allowing it to take on more shock and overload than conventional types. As the outer ring cross section is big, it allows for the bearing to be mounted within a split housing. With the general design and characteristics of heavy-duty needle roller bearings, such components excel in high-speed and misalignment applications.

Beyond such options, one may also procure needle roller bearings with thrust capabilities, track rollers, seals, and much more. Just like thirst bearings, ball bearings, and other bearing options, needle roller bearings often require lubrication oil to remain healthy with high integrity and performance. It is important that lubrication oil is correctly chosen based on the bearing and application in question. If you find yourself in need of needle roller bearings, thrust washer parts, lubrication oil, thrust bearings, or other such hardware, there is no better alternative to Stacked Aviation.

Stacked Aviation is a premier purchasing platform owned and operated by ASAP Semiconductor, and we present customers access to over 2 billion new, used, obsolete, and hard-to-find products. Take the time to explore our massive database at your leisure, and every listing is ready for purchase at any time. Once you have determined the particular items you are most interested in, fill out and submit an RFQ form as provided on our website. Once received, a member of our staff will reach out to you within 15 minutes to provide a customized solution that caters to your unique requirements.

Stacked Aviation is fully committed to quality, enacting a strict NO CHINA SOURCING pledge that guarantees that all parts trace back to a trustworthy manufacturer. Furthermore, countless items undergo rigorous quality assurance measures before shipping out, including comprehensive visual inspections, document verification, and more. As a result of our efforts, we proudly conduct business with AS9120B, ISO 9001:2015, and FAA AC 00-56B accreditation. Experience the future of part procurement today when you get in touch with a Stacked Aviation representative. 


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