For better usage of oil-impregnated bearings (oilless bearings)

Oil-impregnated bearings are inexpensive and need little room to install, and a large quantity of them are used for micromotors, to take an example, as small bearings. Bearings have a certain standard to some extent but we should bare in mind that there is no bearing for all kinds of uses as opposed to the characteristic of ball bearings.

Manufacturing method and property of oil-impregnated bearings

Compression forming of metal powder and sintering it at 700 to 1200 degrees give rise to a mass of porous metal.

Sliding bearings that need no lubricating devices are created through impregnating voids (about 20VOL%) in pieces of porous metal with lubricant.

The bearings created through these methods are called oil-impregnated bearings that utilize porous material by powder metallurgy.

Oil-impregnated bearings have various kinds of creating methods depending on objectives. The materials used range copper, iron, alminum and steel. We should recognize that there is no versatile oil-impregnated bearing that can be used under any condition.

Setting conditions at designing phase

Condition-settings as below are needed at the phase of designing an oil-impregnated bearing.

  1. Making the objective of use clear: confirm what to create, for what it is to be used and where it is to be used ultimately
  2. Environment for usage, range of temperature in the environment
  3. PV value: P value (load), V value (velocity of shaft periphery)
  4. How to install them: would they be press fitted, caulked, self-aligned, open-side or supported at two ends
    Opposite materials: resin or other material, thickness and size tolerance of holes in case of iron boards
  5. Dimensional accuracy of bearings: it is desirable that bearings occupy as much volume in the dimensions as possible. Bearings's volume has its lowest limit.
  6. Kinds of lubricant and viscosity setting
  7. Precision of shaft installation and setting range of bearing's clearance

From the viewpoint of our experience and recognition we have earned through years, we are willing to make sure of your supposition in line with the settings and conditions above and we will be cooperating with you for better consequences offering advice or considering whether it is possible to supply them stably in case any problem or concern could be found.

Points to consider for installation (see our technical guide)

In not a few cases the characteristics of bearings can be ruined as a result of how precise the installation in concentricity, circularity and deformation degree could be.

Hence oil-impregnated bearings can offer the charasteristics of oil-impregnated bearings themselves like dimensional accuracy, oil content, material and other conditions; it is necessary to recognize that it is customers' precision of installation, conditions in use, precision of shaft, clearance and selection of oil that bring out the charasteristics of bearings as a unit.

We will ensure the stable supply of bearings customers designed along its specification. We can only entrust to customers how the characteristics of bearings should be assembled and how these are brought about.

In other words even though an oil-impregnated bearing has its own charasteristics, the technique to bring them out as a unit depends on the technique of assembling the unit in not a few cases.

Feel free to contact and consult with us when you have problems or concerns.

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