Patent ID: 8661866
Filing Date: 2014-03-04
Classification: B21C,F28D

Abstract:
1. An apparatus for producing a flat tube comprising: a material feed unit configured to feed a material to be worked; a tool unit configured to bend said material to be worked fed from said material feed unit; a tension roller unit configured to draw said material to be worked from said tool unit so that said material to be worked is gradually bent by drawing through said tool unit, and for finish correcting said material to be worked that is bent while drawing said material to be worked; and a delivery roller unit configured to deliver a worked product in the form of a flat tube from said tension roller unit; wherein said material feed unit on the upstream of said tool unit is provided with pre-bending means for forming a pre-formed groove in said material to be worked along the longitudinal center axis thereof by pre-bending, wherein the tool unit is configured to bend the material around the pre-formed groove, and wherein said tension roller unit for finish correction has protruded and recessed correction portions for removing work strain occurred in said material to be worked due to the pre-bending, wherein the protruded correction portion is provided with convex correction portions near the end thereof.