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Technical principles

The bearings are standardized components of machinery that transmit forces, moments and rotation movement. Due to the wide range of types, designs and existing sizes in the industry there is a bearing adapted to almost any existing application.

Definition and bearings application

The bearings develop to eliminate the slide friction. This resistance happens when an object slides on other. In some applications the friction for slide is eliminated by a mechanized dry sherry or an element of rolling support that they slide on surfaces smoothed with a thin layer of lubricant.

Using rolling elements is often the best way of reducing the friction for slide. Placing balls or rollers between the surfaces in movement replace the friction by slide for rotary movement. This principle is the base of all the bearings.

Rolling bearing components

Practically all the bearings are formed by 4 fundamental parts: an interior ring, an exterior ring, a few rolling elements, and an element retainer or divider.

The interior ring, the exterior hoop and the rolling elements support the load of the bearing. The separative ring or retainer maintains the separation between the adjacent rolling elements. Without these separative elements, on having entered or having gone out of the load area, the change of speed suffered by the rolling elements gives as turned out impacts, hammering and friction in the rolling elements at big slide speeds.

The divider limits and absorbs some of the forces that the rolling elements suffer while they provide guidance and separation.


The surface on which they roll the rolling elements is called a rolling hoop. Generally the internal hoop is fixed in the axis and the external hoop in the accommodation.

Rolling elements

The rolling elements classify in two big families: balls and rollers.

The rollers bearings can be cylindrical, needles, conical and spherical.

In the ball bearing the contact of the balls with the hoop of rolling of the interior and exterior hoop is theoretically punctual, while the contact in the rollers bearings with the rolling hoops is theoretically linear. For a given load, in case of rollers, the contact pressure between rolling bodies and track is distributed along a line.

In case of balls, it concentrates on only one point. For it, for the same dimensions, the rollers bearings support higher charges and speeds limit less. 


The function of the cage is to separate the rolling bodies so that they preserve its equidistance. In case of bearings of conical, cylindrical rollers, to patella, they make the rolling bodies united with one of the rings.


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