Charles L Durbin

US Patent:

40488349, Sep 20, 1977

Filed:

Apr 15, 1976

Appl. No.:

5/677505

Inventors:

Charles R. Durbin - Louisville KY
Bernard W. Schoenbachler - Louisville KY

Assignee:

General Electric Company - Louisville KY

International Classification:

B21D 1107
B21D 5306

US Classification:

72294

Abstract:

A machine for forming a serpentine heat exchanger having a predetermined length from a continuously formed spine fin tubing. A supply of continuously formed spine fin tubing is directed to a forming and bending head in predetermined increments where it is bent in alternate directions about a central axis to form the serpentine heat exchanger. Prior to the bending action the portion to be bent is deformed into a cross section having its major axis parallel with the longitudinal axis of the tube and perpendicular to the central axis. The following bending operation causes the tube diameter across the major axis to decrease as the wall in the area of the outer curve migrates radially inwardly due to its failure to elongate sufficiently, in effect, the cross sectional area in the completed bent portion is substantially equal to the cross sectional area of the tube before the deforming and bending operation.