Provided are a method for manufacturing a Figure-T shaped metal part using a metal plate or a metal rod split by a method for splitting longitudinally an end part of the metal plate or the metal rod having a rectangular, polygonal, or elliptical shape, in which the length of incision in the split portion can be freely adjusted and smooth split face can be formed; a Figure-T shaped metal part manufactured by such method. The method for splitting is characterized by the process comprising the steps of securing a metal plate by pinching both sides thereof with a clamping device, or securing a metal rod by pinching at least two opposite-facing portions on the periphery thereof with a clamping device; splitting longitudinally by slitting or cleaving the metal plate, or the metal rod, by pressing a slitting punch or a cleaving punch against the face of one end of the metal plate, or the metal rod; and advancing the splitting further by repeating the same operation of pressing the same punch stated above against the cleft of the splitting; and is characterized further in that, in each time of the press-splitting operation, the position of the clamping device on at least one side is moved in advance of the next pressing by a stroke corresponding to the distance from one end of the metal plate, or the metal rod, to the distal end of a split-desired portion.

A material includes a sheet of metal having a first face and an opposed second face, and a metal grain direction. The first face is textured with a first set of texturing features. Each texturing feature of the first set includes, respectively, a groove cut into the first face and extending along a groove axis, and a barb extending from the groove and away from the first face. The texturing features of the first set are arranged in a plurality of rows, and the groove axes of the texturing features in a given row extend generally parallel to the given row. The rows are generally non-perpendicular to the grain direction.

A heat exchanger tube with a tube axis, a tube wall and with ribs extending around on the tube outer side. The ribs have a rib foot, rib flanks and a rib tip, wherein the rib foot projects substantially radially from the tube wall. The rib flanks are provided with additional structural elements which are arranged laterally on the rib flank. First material projections, which extend substantially in the axial and radial direction, adjoin second material projections which extend substantially in the axial and circumferential direction of the tube, wherein the first and second material projections have a common boundary line. The axial extent of the first material projections along this boundary line is less than the axial extent of the second material projections.

A method for texturizing a workpiece uses a die assembly installed within a press having a press ram. The method includes (a) delivering the workpiece onto a center die plate; (b) forcing the press ram against an upper die plate mounted above the center die plate to descend a first contact surface associated with the upper die plate and a plurality of blades mounted to the upper die plate toward the center die plate; (c) actuating horizontal movement of the blades; (d) driving the blades down into the workpiece; and (e) contacting the first contact surface to a second contact surface associated with the center die plate to descend the center die plate in unison with the upper die plate.

A heat exchanger tube with a tube axis, a tube wall and with ribs extending around on the tube outer side. The ribs have a rib foot, rib flanks and a rib tip, wherein the rib foot projects substantially radially from the tube wall. The rib flanks are provided with additional structural elements which are arranged laterally on the rib flank. First material projections, which extend substantially in the axial and radial direction, adjoin second material projections which extend substantially in the axial and circumferential direction of the tube, wherein the first and second material projections have a common boundary line. The axial extent of the first material projections along this boundary line is less than the axial extent of the second material projections.

A method for manufacturing a heat exchanger includes softening a base material having a predetermined hardness, forming fins by cutting and raising a surface of a softened base material by skiving, and hardening the base material by performing a heat treatment on the base material with the fins formed thereon.

A material includes a sheet of metal having a first face and an opposed second face, and a metal grain direction. The first face is textured with a first set of texturing features. Each texturing feature of the first set includes, respectively, a groove cut into the first face and extending along a groove axis, and a barb extending from the groove and away from the first face. The texturing features of the first set are arranged in a plurality of rows, and the groove axes of the texturing features in a given row extend generally parallel to the given row. The rows are generally non-perpendicular to the grain direction.

A method for texturizing a workpiece uses a die assembly installed within a press having a press ram. The method includes (a) delivering the workpiece onto a centre die plate; (b) forcing the press ram against an upper die plate mounted above the centre die plate to descend a first contact surface associated with the upper die plate and a plurality of blades mounted to the upper die plate toward the centre die plate; (c) actuating horizontal movement of the blades; (d) driving the blades down into the workpiece; and (e) contacting the first contact surface to a second contact surface associated with the centre die plate to descend the centre die plate in unison with the upper die plate.

A workpiece includes a material with a face and a first plurality of barbs and a second plurality of barbs extending integrally from the face. Each barb has a height above the face. The barbs of the first plurality are at least 10% higher than the barbs of the second plurality. The first plurality of barbs includes at least 10% of the barbs on the face and the second plurality of the barbs includes at least 10% of the barbs on the face. The barbs of the second plurality of barbs are bent and pointed.

Provided are a method for splitting longitudinally an end part of a metal plate or a metal rod having a rectangular, polygonal, or elliptical shape, in which the length of incision in the split portion can be freely adjusted and smooth split face can be formed; a metal part manufactured by such method; and a method for bonding such metal part. The present invention is characterized by the process comprising the steps of securing a metal plate by pinching both sides thereof with a clamping device, or securing a metal rod by pinching at least two opposite-facing portions on the periphery thereof with a clamping device; splitting longitudinally by slitting or cleaving the metal plate, or the metal rod, by pressing a slitting punch or a cleaving punch against the face of one end of the metal plate, or the metal rod; and advancing the splitting further by repeating the same operation of pressing the same punch stated above against the cleft of the splitting; and is characterized further in that, in each time of the press-splitting operation, the position of the clamping device on at least one side is moved in advance of the next pressing by a stroke corresponding to the distance from one end of the metal plate, or the metal rod, to the distal end of a split-desired portion.