In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.

A support form defining a longitudinal axis is provided. The support form includes a first section, a second substantially solid section, and at least one flow feature form. The first section includes a plurality of unit cells of a first material joined together to form a lattice. The second section includes a second material and surrounds the first section. The at least one flow feature form is defined in the second section and is configured to generate a flow feature on a heat exchanger tube formed by plating the support form.

In one aspect, the present invention relates to a furnace having a heated portion arranged adjacent to an unheated portion. A plurality of straight tubes are formed of a first material and are at least partially disposed in the heated portion. A plurality of return bends are operatively coupled to the plurality of straight tubes. The plurality of return bends are formed of a second material and are at least partially disposed in the unheated portion. The first material exhibits a maximum temperature greater than the second material thereby facilitating increased run time of the furnace. The second material exhibits wear-resistance properties greater than the first material thereby facilitating wear-resistance of the furnace.

A wound tube heat exchanger 10 article that receives a heat exchange fluid and its method of manufacture. The exchanger 10 has one or more layers 12 of a tube 14. In one embodiment, the tube surface is bare. In other embodiments, the outside tube surface is enhanced to produce turbulence. At least some of the layers 12 have an ovate oblong configuration. A pair of opposing linear runs 16,18 is connected by a pair of opposing curved sections 20,22. In some embodiments, the layers are circular, oval or rectangular with radiused corners. An elongate spacer member 24 has forwardly 26 and rearwardly 28 facing edges. Defined within those edges are engagement surfaces 30 that detachably retain the opposing linear runs 16,18.

The present disclosure is directed to a method of making a heat exchanger tube, such as multichannel tubes. The heat exchanger tube may include a plurality of generally parallel flow paths extending between opposite ends. The method may include removing a section of an outer wall along the length of the tube to expose at least some of the plurality of generally parallel flow paths.

A system for preserving and capping tubes includes a compressed air reservoir for storing compressed air, a preservative reservoir containing a supply of a preservative, a nozzle in fluid communication with the compressed air reservoir and the preservative reservoir for injecting the preservative into the interior of a tube, and a capping device configured to insert a cap onto the end of the tube.

A support form defining a longitudinal axis is provided. The support form includes a first section, a second substantially solid section, and at least one flow feature form. The first section includes a plurality of unit cells of a first material joined together to form a lattice. The second section includes a second material and surrounds the first section. The at least one flow feature form is defined in the second section and is configured to generate a flow feature on a heat exchanger tube formed by plating the support form.

A bent heat exchanger includes a first manifold, a second manifold, and a plurality of flat tubes each being configured to communicate the first manifold with the second manifold, and fins between the flat tubes; wherein the flat tube includes a first straight section, a second straight section and a bent section connecting the first straight section with the second straight section. The bent section includes the first twisted section connected to the first straight section, the second twisted section connected to the second straight section, and the connecting section connecting the first twisted section with the second twisted section, and the connecting section of the flat tube has a substantially flat shape or a flat arc shape. In this way, the height of the bent heat exchanger can be reduced, which facilitates the installation and improves the heat exchange performance of the heat exchanger.

A method and system for manufacturing a hairpin tube. The method includes cutting a coil of tube to provide a plurality of lengths of tubes, and bending each length of tube to form a plurality of hairpin tubes. A lubricant is then atomized with an injector nozzle, and injected into at least one open end of each hairpin tube. After lubricating the hairpin tubes, the legs of each hairpin tube are expanded.

A heat exchanger having a primary flow path arranged to contain a first heat exchanging medium. A secondary flow path arranged to contain a secondary heat exchanging medium, wherein the primary flow path surrounds the secondary flow path for exchanging heat between the two paths.