TABLE OF CONTENTS Lubricants are the lifeblood of a machine tool. Without adequate lubrication, spindles would seise, slides could not slide and gears would rapidly disintegrate. However, the reduction of bearing friction, vital though it is, is by no means the only purpose of machine-tool lubrication. Many machines are operated by hydraulic power, and one oil may be required to serve as both lubricant and hydraulic fluid. The lubricant must be of correct viscosity for its application, must protect bearings, gears and other moving parts against corrosion, and, where appropriate, must remove heat to preserve working accuracies and alignments. It may additionally serve to seal the bearings against moisture and contaminating particles. In some machine tools the lubricant also serves the functions of a cutting oil, or perhaps needs to be compatible with the cutting oil. In other tools an important property of the lubricant is its ability to separate rapidly and completely from the cutting fluid. Compatibility with the metals, plastics, sealing elements and tube connections used in the machine construction is an important consideration.
In machine-tool operations, as in all others, the wisest course for the user is to employ reputable lubricants in the manner recommended by the machine-tool manufacturer and the oil company supplying the product. This policy simplifies the selection and application of machine-tool lubricants. The user can rest assured that all the considerations outlined above have been taken into account by both authorities.
The important factors from the point of view of lubrication are the...
