Disclosed is a tube bending system for forming a hairpin tube, the tube bending system including: a supply of lubricant; a supply of atomizing medium; a bend mandrel, the bend mandrel comprising: a mandrel body and a mandrel head, the mandrel head being positionable within a length of a tube to be bent, the mandrel head including a downstream end with an orifice configured for injecting lubricant into the tube.

A heat exchanger includes tube expansion portions provided respectively on a plurality of heat transfer tubes such that outer peripheral surfaces of the heat transfer tubes are respectively pressed against inner peripheral surfaces of a plurality of first holes provided in a side wall portion of a case, and a plurality of first concave surface portions provided in an outer surface of the tube expansion portion so that first gaps, into which brazing material of a first brazed portion advances, are formed between the outer surface of the tube expansion portion and the inner peripheral surface of the first hole. At least one of the plurality of first concave surface portions is positioned in an outside peripheral surface portion of the outer peripheral surface of the heat transfer tube. According to this configuration, the strength with which the heat transfer tubes are attached to the case can be increased while simplifying a manufacturing operation and reducing the manufacturing cost.

A heat exchanger includes tube expansion portions provided respectively on a plurality of heat transfer tubes such that outer peripheral surfaces of the heat transfer tubes are respectively pressed against inner peripheral surfaces of a plurality of first holes provided in a side wall portion of a case, and a plurality of first concave surface portions provided in an outer surface of the tube expansion portion so that first gaps, into which brazing material of a first brazed portion advances, are formed between the outer surface of the tube expansion portion and the inner peripheral surface of the first hole. At least one of the plurality of first concave surface portions is positioned in an outside peripheral surface portion of the outer peripheral surface of the heat transfer tube. According to this configuration, the strength with which the heat transfer tubes are attached to the case can be increased while simplifying a manufacturing operation and reducing the manufacturing cost.

An apparatus for forming and sealing an adjustable duct member for use in an air handling system. At least one work station accommodates a tapered work piece. A repositionable die is positioned relative to the work piece, and a cutting and forming assembly cooperates with the repositionable die to cut the work piece and form a coupling bead to reconnect the members together. A sealing assembly cooperates with the first repositioning die to seal the coupling bead in the first and second members. The work station includes an insertion channel having predetermined dimensions to accommodate at least a portion of the work piece. A clamping assembly is associated with the insertion channel to securely hold the tapered work piece at the predetermined position during the cutting and forming and sealing operations.

An apparatus for forming and sealing an adjustable duct member for use in an air handling system. At least one work station accommodates a tapered work piece. A repositionable die is positioned relative to the work piece, and a cutting and forming assembly cooperates with the repositionable die to cut the work piece and form a coupling bead to reconnect the members together. A sealing assembly cooperates with the first repositioning die to seal the coupling bead in the first and second members. The work station includes an insertion channel having predetermined dimensions to accommodate at least a portion of the work piece. A clamping assembly is associated with the insertion channel to securely hold the tapered work piece at the predetermined position during the cutting and forming and sealing operations.

A method for producing a microchannel bundle heat exchanger (1) includes providing a multiplicity of tubular microchannels (2); incorporating the microchannels (2) in a weaving device; interweaving the tubular microchannels (2) with a plurality of warp wires (3) in the weaving device, and generating at least one heat exchanger mat (4) from the tubular microchannels (2) which are connected to one another by means of the warp wires (3); shaping at least one heat exchanger pack (8) from the at least one heat exchanger mat (4), in particular by folding and/or rolling up the heat exchanger mat (4); and adhesively bonding the tubular microchannels (2) at two mutually opposite end sides (9, 10) of the heat exchanger pack (8).

A method for producing a microchannel bundle heat exchanger (1) includes providing a multiplicity of tubular microchannels (2); incorporating the microchannels (2) in a weaving device; interweaving the tubular microchannels (2) with a plurality of warp wires (3) in the weaving device, and generating at least one heat exchanger mat (4) from the tubular microchannels (2) which are connected to one another by means of the warp wires (3); shaping at least one heat exchanger pack (8) from the at least one heat exchanger mat (4), in particular by folding and/or rolling up the heat exchanger mat (4); and adhesively bonding the tubular microchannels (2) at two mutually opposite end sides (9, 10) of the heat exchanger pack (8).

The present invention is directed to providing a tube assembly for a heat exchanger or heat management apparatus in which the tube assembly can be integrally assembled using inner fin tubes having a two-row structure and drainage performance and corrosion resistance performance can be improved. The tube assembly for the heat exchanger or heat management apparatus includes a first- and second- row tube including an inner fin type tube respectively, a central connection portion that connects the first-row tube to the second-row tube, and a header in which a first- and a second-row tube hole, into which ends of the first- and the second-row tube are inserted, are arranged, wherein a cut portion formed in the direction opposite to the ends of the first- and the second-row tube inserted into the header is included in the central connection portion.

A heat exchanger includes plural flat tubes each having a flat cross section, and plural flat-tube U-bends each having a flat cross section and a U-shape in external appearance. Plural flat-tube columns each made up of the plural flat tubes installed in plural tiers in a set direction are arranged in a direction intersecting the set direction and in a staggered manner. Each of the plural flat-tube U-bends is placed in a pair of coupling portions of the plural flat tubes. Each of the pair of coupling portions is placed in one of a pair of the plural flat-tube columns. The plural flat-tube U-bends are twisted such that major axes of flat cross sections in both end portions of each of the plural flat-tube U-bends are oriented in the same directions as major axes of flat cross sections of the plural flat tubes connected to the both end portions.

A heat exchanger includes plural flat tubes each having a flat cross section, and plural flat-tube U-bends each having a flat cross section and a U-shape in external appearance. Plural flat-tube columns each made up of the plural flat tubes installed in plural tiers in a set direction are arranged in a direction intersecting the set direction and in a staggered manner. Each of the plural flat-tube U-bends is placed in a pair of coupling portions of the plural flat tubes. Each of the pair of coupling portions is placed in one of a pair of the plural flat-tube columns. The plural flat-tube U-bends are twisted such that major axes of flat cross sections in both end portions of each of the plural flat-tube U-bends are oriented in the same directions as major axes of flat cross sections of the plural flat tubes connected to the both end portions.