A tube stay mounting assembly includes a press assembly having a housing and a top block configured to flatten fins on a first surface of a finned tube. A press arm is operable to move the top block vertically with respect to the housing. A bottom block is configured to flatten fins on a second surface of the finned tube when the press arm is rotated and moves the top block downwardly. A tube stay clamping assembly includes a clamping housing configured to receive a tube stay having a top, bottom, rear, and front walls, the tube stay being configured to receive a flattened portion of the finned tube. A clamping arm is connected by linking arms to a clamping block, the clamping block configured to engage and force the front wall into snap-fit engagement with the top wall of the tube stay.

Methods for expanding a tube to create a tight fit or an interference fit with one or more fins for the manufacture of a heat exchanger are disclosed. The methods can include providing an internal pressure to the tubes in a successive pulsing manner with each pulse having a short duration. The methods can include creating a temperature differential between the bend sections of the tubes and the straight sections of the tubes such that the bend section has a lower temperature than the straight sections. The methods can include creating an external pressure differential between the bend sections of the tubes and the straight sections of the tubes such that the external pressure acting on the bend sections is greater than the external pressure acting on the straight sections.

Systems and methods for pressure expanding a tube to fit a heat exchanger fin are disclosed. The systems can include one or more pressure relief devices, and each pressure relief device can be configured to release at least some pressurized fluid via a respective auxiliary flow path in response to a pressure of the pressurized fluid being greater than a predetermined pressure relief threshold.

A heat exchanger includes a flat tube and a plurality of fins. The plurality of fins are arranged on the flat tube and inclined with respect to a longitudinal direction of a cross section perpendicular to an axis of the flat tube. The plurality of fins may be inclined at different angles with respect to the axis of the flat tube. The flat tube may include a straight portion on which the plurality of fins are arranged, and a bend on which at least one fin other than the plurality of fins is arranged. The at least one fin extends perpendicularly to the axis of the flat tube.

A tube stay mounting assembly includes a press assembly having a housing and a top block configured to flatten fins on a first surface of a finned tube. A press arm is operable to move the top block vertically with respect to the housing. A bottom block is configured to flatten fins on a second surface of the finned tube when the press arm is rotated and moves the top block downwardly. A tube stay clamping assembly includes a clamping housing configured to receive a tube stay having a top, bottom, rear, and front walls, the tube stay being configured to receive a flattened portion of the finned tube. A clamping arm is connected by linking arms to a clamping block, the clamping block configured to engage and force the front wall into snap-fit engagement with the top wall of the tube stay.

A heat exchanger includes a plurality of plate-shaped fins disposed at intervals, and a plurality of heat transfer tubes disposed to be inserted into through holes of the fins in a direction perpendicular to the fins. In each of the fins, a starting hole is formed between adjacent through holes, and the starting hole serves as a start point of bending of the fins and has a vertex portion at a bending portion of each fin which is close to an edge thereof. In each of the fins, a cut is made to connect the other edge of the fin and a side of the starting hole which is located opposite to the vertex portion of the starting hole. The above each fin is bent at the vertex portion of the starting hole, by opening the cut from the starting hole.

A heat exchanger includes a plurality of heat transfer tubes housed in a predetermined case, a connecting tube body for connecting the plurality of heat transfer tubes, a predetermined tube expansion portion provided on each heat transfer tube, a first peripheral wall portion provided on the tube expansion portion, and a second peripheral wall portion that is positioned on an end portion of the connecting tube body and fitted to the tube expansion portion, wherein the first and second peripheral wall portions have different sectional shapes and are fitted together in a partial contact state including predetermined contact and non-contact portions. According to this configuration, the heat transfer tubes can be fixed to a side wall portion of the case and the connecting tube body can be connected to the heat transfer tubes easily and appropriately.

A heat exchanger includes a heat exchange tube including a bent section, and first and second sections. The bent section includes a section to be bent before bending, and the section to be bent includes a protruding section. A plane parallel to a length direction of a first header and parallel to a length direction of the first section, and also perpendicular to a width direction of the first section is a first plane before the bent section is bent. In the first plane, a minimum distance from a projection line of a first side edge of the protruding section to a projection line of a first side edge of the first section is H, and a minimum distance from the projection line of the first side edge of the first section to the projection line of the first side edge of another adjacent first section is L, and H≥L.

Systems and methods for pressure expanding a tube to fit a heat exchanger fin are disclosed. The systems can include one or more pressure relief devices, and each pressure relief device can be configured to release at least some pressurized fluid via a respective auxiliary flow path in response to a pressure of the pressurized fluid being greater than a predetermined pressure relief threshold.

Disclosed is a method for producing a heat exchanger. The heat exchanger includes heat exchange tubes extending along a first direction and arranged along a second direction perpendicular to the first direction, and a fin. The fin is provided with fin grooves for mounting the heat exchange tubes, and each fin groove is provided with an opening on one side in a third direction perpendicular to the first direction and the second direction. The method includes: providing a heat exchange tube preform, the heat exchange tube preform having a maximum size in a second direction; providing a fin preform, a fin groove of the fin preform having a minimum size in the second direction, and the maximum size being greater than the minimum size; inserting the heat exchange tube preform into the fin groove of the fin preform, so as to generate a predetermined contact pressure between the heat exchange tube preform and the fin preform by means of the elastic deformation of at least one of the heat exchange tube preform and the fin preform; and welding the heat exchange tube preform and the fin preform together.