Detail of JB/T 6541-2004

Introduction of JB/T 6541-2004

1 Scope This standard specifies the shape and structure elements the cold extrusion pieces shall conform to. This standard is applicable to cold extrusion pieces of ferrous metal and nonferrous metal. 2 Symbol r1, r2- inner surface corner radius of cold extrusion pieces, mm R1, R2- external surface corner radius of cold extrusion pieces, mm 2a- Inlet angle of forward extrusion cavity die, (°); β- cone apex angle of backward extrusion terrace die, (°)； S- Wall thickness of extrusion piece, mm h- Flange thickness or base thickness of extrusion pieces, mm; h1- the gross thickness of extrusion pieces, mm; d1- internal diameter of cold extrusion pieces, mm; D1- outerior diameter of cold extrusion pieces, mm; D0- blank diameter, mm; L0- blank diameter, mm; L1- The partial extrusion length of forward extrusion piece, hole depth of backward extrusion cup shell, mm; l1- the recess depth of extrusion pieces, mm; 3 Classification of Cold Extrusion Pieces 3.1 Cold Extrusion Pieces In Shape Classification a) rotational symmetry pieces b) Simple axial symmetry and asymmetric pieces c) The extrusion pieces in the groove and tooth form. 3.2 Cold Extrusion Pieces Are Classified According to Processes 3.2.1 Forward extrusion

Contents of JB/T 6541-2004

Foreword I 1 Scope 2 Symbol 3 Classification of Cold Extrusion Pieces 3.1 Cold Extrusion Pieces In Shape Classification 3.2 Cold Extrusion Pieces Are Classified According to Processes 4 Structural Elements of Cold Extrusion Pieces 4.1 Determined General Principals of Structural Elements 4.2 Draw Ratio of Backward Extrusion Cup Shell Pieces 4.3 Ratio of The Base Thickness and Wall Thickness of Cup Backward Extrusion Piece 4.4 Recess Die Inlet Angle of Forward Extrusion 2 and Terrace Die Cone Apex Angle of Backward Extrusion 4.5 Gross Position and Thickness of Combined Extrusion Pieces h 4.6 Fillet Radius and the Round Radius of Cold Extrusion 4.7 Recess Dimension and Position of Cold Extrusion Piece