A bearing “bears” and controls the load of machine parts. They are devices that support, guide, and reduce the friction of the motion of a rotating, sliding, or oscillating shaft or disk. They come in many forms, and Nordex provides a full range of precision bearing assemblies and components.
Bearings, Bushings and Idlers
Bushings are simple one-piece tubular sleeves that can receive a shaft and support its static or moving position. They are mainly used for alignment. Bushings may be straight-sided or flanged.
Journal bearings (aka journal assemblies) or plain bearings are assemblies that consist of a shaft (journal) that rotates in a supporting sleeve (bushing) comprised of a single material or material blended with a polymer or babbit layer, either lubricated or self-lubricating-dry. This type of assembly has no rolling elements and has fewer moving parts and greater friction than ball or linear bearings.
Ball Bearings and Linear Bearings are assemblies with rotating elements such as balls or needles (rollers) inside retainers comprised of inner and outer raceways. They are designed to constrain and move loads with a minimum of friction. Linear bearings facilitate linear motion and may be comprised of a circular bearing and shaft, or a slide plate/slide table and matching surface.
Idlers are devices that tension timing belts but do not transmit power. Instead of a shaft rotating within a sleeve, the sleeve (idler) rotates around the shaft, providing nearly frictionless movement of a belt across the idler. If you think of old film projectors, the film in simplest terms is a timing belt, and you see several of these idlers in the projector. Another way to visualize it is as a pulley that provides a frictionless way to move a belt or cord over a support.
Ball bearings are precision instruments, and Nordex is expert in ball bearing handling techniques. The company maintains a Class 100 Certified Clean Room which is used for cleaning and lubricating ball bearings. A lubricated bearing has a shelf life of one year, after which it must be cleaned and relubricated. The techniques used in the process of relubrication are those used by New Hampshire Ball Bearing. We were trained by NHBB as a re-lubrication facility.
Here are just a few of the guidelines we follow, which we also recommend to our customers:
- Never use bare hands; use talc-free surgical gloves or finger cots
- Wear caps, shoe covers and smocks made of lint-free plastic yarn
- Work space must be a clean, uncontaminated area
- Store bearings in their original container until they are installed
- Never leave bearings exposed in uncovered containers
- Bearings should not come in contact with any source of magnetism
- Keep bearings in a dry environment to prevent corrosion
Hundreds of lubricants are available for ball bearings, each type having particular characteristics. Contact the engineering staff at Nordex with your tribology questions to ensure selection of the proper lubricant for your specific application.