METHOD OF MAKING BUILTUP PRODUCTS WITH LENGTHWISE LAMINARITY Russian patent published in 1998 - IPC

FIELD: plastic metal working, particularly processes for making builtup-thickness blanks for manufacturing tubes with clad working surfaces. SUBSTANCE: method for making builtup products with lengthwise laminarity includes steps of arranging one hollow blank inside another with use of inner blank made of less strength material than outer one; assembling blanks and fixing them one relative to another; heating builtup blank; placing it onto needle for further extruding through cone die due to placing said blank in container and applying axial compression effort to its ends. Novelty is arranging one of said blank only along a part of length of other blank, applying axial compression effort to end of blank of less strength material for forming thickened portion turned towards contacting surface; axially moving blank of less strength material in conditions of active friction; displacing said thickened portion relative to joined surface of blank of less strength material. EFFECT: enhanced efficiency. 6 dwg