Critical review of drawing with particular reference to lubrication

Abstract The following survey shows briefly the relationship between metalworking theory and modern lubrication theories. Lubrication phenomena cannot be explained by one exclusive theory. Evidence suggests that the so-called coefficient of friction remains constant over a wide range of lubricating conditions for the same pair of metals and this justifies its use for the calculation of drawing load and die bursting pressures. It is concluded from the literature that some form of hydrodynamic lubrication in drawing is desirable and the reduction in wear rate obtainable makes the effort of ensuring this justifiable. Research effort directed along PHL lines should cause considerable advances.