Mechanical Testing of Cutting Fluids

THIS paper dealt with a very important branch of lubricant testing. Methods of field testing cutting oils have presented difficult problems since they were first used and laboratory tests are also difficult because of the many varying operating conditions during test. The author described tests for drilling and turning which are designed to evaluate cutting oils. This work emphasises the difficulties involved. The efficiency of a cutting tool is dependent mainly upon cooling and lubrication, the physical requirements of the former being known. Reduction in friction will lower the cutting forces at the tool and result in more economical cutting, but the complex nature of the cutting process does not lend itself readily to a fundamental study of these properties, for the many variables present influence the chip form on which depends the ability of the lubricant to penetrate into the cutting region.