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With many thousands of "cheap bearings" in our Manchester based warehouses and instant access to all major European manufacturers' current output, often at less than wholesale trade prices, bearings index is your first point of reference for bearing procurement.

Bearings are simple machines found in all those instruments and machines, which roll or tend to roll and are responsible for making the things roll. It is only because of the bearings that electric motors and inline skate wheels spin so smoothly without making much noise. If there were not bearing in our life then we would be constantly replacing machines parts and instruments wore out from friction. Bearings have made several things in our life possible. 

Bearing is a mechanical hardware device that allow constrained relative motion between two parts, typically linear or rotational movement. It supports two parts and reduces friction between them. The main objective of bearings is to enable smooth relative movement between two objects or different parts of the same object. 

Things tend to roll better than slide and that concept works behind bearings. For example wheels in your bike are same as bearings, which facilitate its movement. Just think how much it would be difficult without wheels. 

When things slide there is a relative motion between two surfaces involved. Due to the friction between the two surfaces a force tend to slow down the motion and finally stop the motion. But if the two surfaces roll over each other instead of sliding, friction is greatly reduced and the motion becomes smooth. nsk Bearings reduce friction by providing smooth metal balls, and a smooth inner and outer metal surface for the balls to roll against. These balls bear the load and allow the device to spin smoothly.

There is no definitive evidence but the concept of bearings date as back as construction of the pyramids of Giza. At those times tree trunks were used as linear bearing to laid down under sleds. The concept of ball bearings go all the way back to the Roman Empire as ball bearings were found on the Roman Nemi ships constructed in about 40 A.D. However Leonardo Da Vinci is credited with the first practical designs. In 1791 Philip Vaughn, an English carriage maker and inventor, patented the first axle assembly to use ball bearings. Self-aligning design of the ball bearing is attributed to Sven Wingquist of the SKF ball-bearing manufacturer, when in 1907 he was awarded Swedish patent No. 25406 on its design. 

Bearings are made of a variety of materials of which the most common and important is stainless steel. Since bearings have to bear a lot of stress, the steel with which it is made needs to be very strong. The quality of steel used determines the durability of the bearing. Cheap bearings are made of hardened carbon-steel or pressed sheet metal, both of which are usually not recommended. The standard industry classification for the steel in some bearings is 52100, which contains 1% chromium and 1% carbon. Such steels can be made very hard and tough by heat treating. 440C stainless steel are used to manufacture ntn bearings which can face rusting threats.

The diversified applications of bearings in different industry and instruments have forced engineers to discover new materials for making bearings that suit specific applications. For example ceramics has become quite popular in making skateboard bearings. Apart from stainless steel other materials used for manufacturing metallic bearings include bronze, nickel, brass, iron, aluminum, copper, etc. Materials used for manufacturing non metallic bearings include ceramics, glass, plastics (e.g., nylon, polyoxymethylene, teflon, UHMWPE, etc.), and even sapphire. Wood was the main material for making bearing in ancient ages. 

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