DESIGN CONSIDERATIONS
LENGTH / DIAMETER RATIOS
For most press fit sleeve type METALON a bearing, a length/diameter ratio of 1.25:1 is optimum and generally provides lowest friction. In the marine field, for water lubricated propeller shaft bearings, a standard length/diameter ratio of 4:1 has been used. With METALON this can be reduced to 2:1.

WALL THICKNESS
In most existing applications, where METALON is used as a replacement bearing, configuration of the equipment governs the wall thickness. Ideally, wall thickness need be only governed by required wear-down potential and what is needed for a secure interference fit. A metallic bushing can be used together with METALON to reduce wall thickness if desired. If wall thickness can be controlled, generally a thinner wall is preferred because this will facilitate heat dissipation and improve the shape factor.
FITTING
METALON presents few fitting problems and recovers quickly from rough handling during fitting. The easiest way to fit an METALON bearing is by freezing it first. It can, however be pressed into the housing. In no case should the housing be heated to facilitate fitting. Practical experience suggests that small bearings are easily pressed. While longer ones are shrunk using dry ice or liquid nitrogen. An entry chamfer on the bearing and/or a rounded corner on the housing will facilitate press fitting.

LIMITED WARRANTY AND LIMITATION OF LIABILITY
METALON can be specified as non-lubricated for relatively low & ,medium speed applications where regular lubrication is not possible or where abrasives may be attracted to grease lubrication. METALON - OILON exhibits the best properties for dry running due to the high lubricant content of its formulation. Built in lubricants are released as pressure is exerted on the bearing which in turn reduces friction and heat generation. The appropriate method of lubrication can be selected by referring to the Design Guide Section.

WEAR
Wear is destructive removal of material from contacting surfaces moving relative to one another. Wear can take several forms and, as a highly complex process, is difficult to predict.

ADHESIVE WEAR
Adhesive wear occurs when minute peaks of two rough surfaces contact each other and wed or stick together removing a wear particle.  Adhesive wear of METALON is very minimal at normal temperatures and pressures, nut becomes the dominant wear mode at very high temperatures when surface melting starts to take place. An important point is that friction is not involved in adhesive wear. A common misconception is that wear increases as friction increases and although this can occur, it is not always the case. In metals, this type of wear is called “ scuffing if not too severe and “ galling , “ scoring , or “ wiping , if it is severe.

ABRASIVE WEAR
Abrasive wear involves the wearing of a soft surface by a hard particle. Examples are sandpaper or a grinding wheel (two body abrasion) or sand particles between a bearing and shaft (three-body abrasion). The best method for minimizing abrasive wear is to have one surface very hard and the second relatively soft and complaint. Abrasive particles are allowed to be pushed into the soft surface and roll or slide through the contact sector with very little damage to the shaft or bearing. Tests have shown that optimum life in an abrasive environment for a very hard shaft and an METALON Composite bearing. Other types of abrasive wear common to bearings include impact abrasion and slurry abrasion. Impact abrasion would occur in a chute liner pumping and slurry abrasion in a pump when pumping slurry.

WEAR COMPARISON
Extensive wear testing of METALON has been done in Indian industry. All the bearing materials were compared in tests on a specially designed machine using circulating abrasive slurry.

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