JOURNAL BEARING

A 'journal bearing' is a simple bearing in which a shaft, or "journal", rotates in the bearing with a layer of oil or grease separating the two parts through fluid dynamic effects. The shaft and bearing are generally both simple polished cylinders with lubricant filling the gap. Rather than the lubricant just "reducing friction" between the surfaces, letting one slide more easily against the other, the lubricant is thick enough that, once rotating, the surfaces do not come in contact at all. If oil is used, it is generally fed into a hole in the journal under high pressure, as is done for the most heavily-loaded bearings (main, big-end and camshaft) in an automobile engine. A simple oil "slinger" in the sump and an appropriate feed hole in the bearing shell are considered adequate for small single-cylinder engines, such as those used in lawnmowers.
Common materials used for journal bearings include white metal, babbit metal and phosphor bronze.

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See also

External links

See also

★ Plain bearing

★ Fluid bearing

External links

★ Reliability Direct: Field Application Note: Journal Bearing