A tube transition fitting is formed having a first end, a second end, a head, a body, a weld area, and a first wall thickness and second wall thickness. A tube seat is formed on a surface connected to the body, the surface being adjacent a transition from the first wall thickness to the second wall thickness. A tube transition assembly includes a header portion, the tube transition fitting, and a heat exchange tube, each being connected using one or more simplified and/or heat-optimized connections.

An aluminum alloy brazing sheet has a 3XXX, 1XXX or 6XXX core, an interliner and a 4XXX brazing layer without added Mg. The interliner has Bi and Mg, the magnesium migrating to the surface of the brazing sheet during brazing and reducing the aluminum oxide to facilitate brazing without flux in a controlled inert atmosphere with reduced oxygen.

A flat plate heat exchanger module for use in aerospace applications, automotive applications, industrial applications or similar. The flat plate heat exchanger module comprises a stack of heat exchanger plates, where at least one of the heat exchanger plates further comprises at least one elongated aperture extending across the surface of the heat exchanger plate. This elongated aperture is in fluid isolation from the fluid flowing across the surface of the heat exchanger plate. The use of at least one elongated aperture throughout the stack of heat exchanger plates minimises the overall effect of the expansion and contraction of the metal due to exposure to high temperature gradients. A method of manufacturing such a heat exchanger module is also provided.

Each heat exchange tube of a condenser is formed of a first brazing sheet having a core material and a first brazing material covering the core material. The tank body of each header tank is formed of a second brazing sheet having a core material and a third brazing material covering the core material and being lower in flowability than the first brazing material. In a region of a surface of each protrusion portion facing the corresponding heat exchange tube, the region having a predetermined width as measured from the projecting end, the core materials of the two brazing sheets are brazed together by means of the first brazing material. In the region other than the brazed portion, the core materials of the two brazing sheets are brazed together by means of a fillet formed of a mixture of the first and third brazing materials.

An enclosed heat sink with a side wall structure is provided. The side wall structure includes a welding body having a first welding plane and a side wall structure having a second welding plane. The first welding plane and the second welding plane are pressured and welded to each other, such that the welding body and the side wall structure encapsulate a cavity. A width of the second welding plane is smaller than a width between two side surfaces of the side wall structure.

A method of constructing a plate fin heat exchanger includes joining a first side bar formed from a nickel-iron alloy to a first end of a fin element formed from a nickel-iron alloy through a first nickel-iron alloy bond, and joining a second side bar formed from a nickel-iron alloy to a second end of the fin element through a second nickel-iron alloy bond to create a first layer of the plate fin heat exchanger. The fin element defines a fluid passage.

The method for manufacturing a heat exchanger plate includes a lid groove closing process to insert a lid plate into a lid groove formed at a periphery of a concave groove opening to a surface of a base member; and a primary joining process to perform friction stirring while relatively moving a primary joining rotary tool equipped with a stirring pin along a butting portion of a side wall of the lid groove and a side surface of the lid plate, and in the primary joining process, the rotating stirring pin is inserted into the butting portion, and the friction stirring is performed in a state of only the stirring pin being in contact with the base member and the lid plate.

Provided is ferritic stainless steel having excellent brazeability and excellent corrosion resistance to condensed water in an environment in which the steel is used for an exhaust heat recovery device or an EGR cooler. A ferritic stainless steel has a chemical composition containing, by mass %, C: 0.025% or less, Si: 0.40% to 2.0%, Mn: 0.05% to 1.5%, P: 0.05% or less, S: 0.01% or less, Cr: 16.0% to 30.0%, Mo: 0.60% to 3.0%, Ni: 0.10% to 2.5%, Nb: 0.20% to 0.80%, Al: 0.001% to 0.15%, N: 0.025% or less, and the balance being Fe and inevitable impurities, in which relational expressions (1) and (2) below are satisfied.
C+N≤0.030%  (1),
2Si+Ni≥1.0%  (2),
(in relational expressions (1) and (2), C, N, Si, and Ni each denote the contents (mass %) of the corresponding elements).

A heat exchanger includes a plurality of flat tubes and a coupling header. The flat tubes are disposed in multiple tiers along a predetermined tube tier direction and in multiple rows so as to be adjacent to each other in a tube row direction intersecting the tube tier direction and the longitudinal direction of the flat tubes. The coupling header is formed by joining a first member to a plurality of second members in the tube tier direction. The first member has a plurality of through holes through which pass the first end portions of the flat tubes. The second members when joined to the first member forming a plurality of coupling passages where the first end portions of the flat tubes adjacent to each other in the tube row direction communicate with each other.

One of a first metallic pipe containing a first metal as a main component and a second metallic pipe containing a second metal as a main component includes an expanded-diameter connecting part which is formed at an end part of the one metallic pipe. An inner diameter of the end part is greater than an inner diameter of an adjacent part that is adjacent to the end part. An intermetallic compound layer of the first and second metal is present at an interface of the first and second metal located between a brazing filler metal and the one or the other of the metallic pipes. A thickness of the intermetallic compound layer is configured such that the thickness of an end portion on the side of a base end is smaller than the thickness of an end portion on the side of an open end.