Steven D Nelson

US Patent:

42625181, Apr 21, 1981

Filed:

Jul 16, 1979

Appl. No.:

6/058058

Inventors:

Todd D. Creger - Peoria IL
Steven R. Nelson - Dunlap IL
Paul L. Wright - Peoria IL

Assignee:

Caterpillar Tractor Co. - Peoria IL

International Classification:

B21D 4102

US Classification:

72393

Abstract:

A tube expander (10) for extrudably deforming tubes (12) into conformity with a flange (16) has a plurality of first and second forming members (28,30) circumferentially arranged on a mandrel (20). In an initial position, the forming members (28,30) are axially offset and radially retracted for ease of insertion into the bore (13) of the tube (12). After insertion, the mandrel (20) is partially withdrawn by an actuator (64) and by such action, the forming members (28,30) are brought together in an abutting, axially aligned, and radially expanded relationship such that workpiece-contacting surfaces (40,42) of the forming members (28,30) are brought into substantially continuous circumferential contact with the tube bore 13. The workpiece-contacting surfaces (40,42) are maintained in continuous circumferential contact with the tube bore 13 as the forming members (28,30) and the mandrel (20) are withdrawn from the tube end, thereby uniformly extruding the tube.