HYDRODYNAMIC DRAWING OF MULTIPLE GAUGE METAL STRIP

摘要

Multiple gauge metal strip is prepared by a process which comprises shaping strip material of rectangular cross section to form regions of at least two variable thicknesses defining a stepped surface configuration in at least one of the broad surfaces of said strip, and drawing the shaped strip through a die which defines said cross sectional configuration to produce a reduction of said strip to final dimension, wherein said drawing step is performed without direct surface-to-surface contact between said strip and said die, such that the width dimension of said strip is unchanged and the ratio of strip surface to strip cross sectional area changes by at least 30%. The drawing method of this invention employs hydrodynamic lubrication and can achieve one-pass cross sectional reductions of from 39 to 55%.