Principles of oil-impregnated bearings

The Peace-lon oil-impregnated bearings are produced on the basis of these principles.

Sintered oil-impregnated bearings are, when classified among bearings, a kind of "sliding bearings".

In general, sliding bearings are explained by a system called complete lubrication (oil film formation); the friction coefficient of oil-impregnated bearings is as large as 0.1 to 0.2, as opposed to other common bearings' 0.02 to 0.05, besides the rise in temperature gets rather high. However, other common bearings have a good performance only when oil is supplied in an ideal manner, and once oil supply stops, seizure can be a matter of concern.

Oil-impregnated bearings pose us very little concern like above. Actually, there have been many cases where they were operated without being seized with no oil supply and under severe conditions, even when they were already emitted smoke.

OIL CIRCULATION MECHANISM IN SINTERED OIL-IMPREGNATED BEARINGThe figure at the right gives a schematic illustration of the oil circulation mechanism during operation of a sintered oil-impregnated bearing ("bearing" hereafter).

It illustrates that oil from the internal pores of the bearing replenishes the oil in the bearing clearance through a pump-like action created by the rotation of the shaft, thus an oil film is formed on the sliding surface between the shaft and the bearing. It also explains that part of the oil in this film escapes through the pores in the lower sliding surface and migrates to the no-load region at the top through the pores of a bearing, and thus a circulation of oil is established.

The advantages of sintering technology

Sintering is the technology where metal powder is pressed together, heated to become a mass under the temperature of 700 to 1200 degrees.

  1. Avoiding waste of material
  2. Mixing various kinds of metal powders as you want
  3. Manufacturing parts from sintered metal, utilizing its charasteristic
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