Note:  Do not rely on this information. It is very old.


Journal, in engineering, is that part of a shaft or or an axle that is supported at the bearings. It must be circular in section, and is usually made cylindrical with slight enlargements at each end to prevent lateral motion of the axle. The journal requires careful designing; if the amount of bearing surface is too small, it will become heated under the excessive pressure, the lubricating material will be squeezed out, and the journal will cut into the bearing.