A heat exchanger includes a tube expansion portion provided on a heat transfer tube such that an outer peripheral surface of the heat transfer tube is pressed against an inner peripheral surface of a first hole provided in a side wall portion of a case, and a first concave surface portion that is provided in a part of an outer surface of the tube expansion portion and forms a first gap, into which brazing material of a first brazed portion advances, between the outer surface of the tube expansion portion and the inner peripheral surface of the first hole. Thus, the attachment strength of the heat transfer tube can be improved by means of a simple configuration.

A heat exchange cell is described comprising a containment casing comprising a rear wall, a front wall and a peripheral side wall, a helically-shaped heat exchanger comprising at least one tubular duct for the flow of a first heat transfer fluid coiled about a longitudinal axis of the helix according to a plurality of coils and mounted in the containment casing; a feeding zone of a second heat transfer fluid, intended for the heat exchange with the first heat transfer fluid, defined in the casing coaxially and internally with respect to the heat exchanger; a first chamber for collecting the second heat transfer fluid externally defined with respect to the heat exchanger between a radially outer wall thereof and the peripheral side wall of the containment casing; and a second chamber for collecting the second heat transfer fluid at least partially delimited by at least one separating element.

A transfer tube for a thermal transfer device can include at least one wall having an inner surface and an outer surface, where the inner surface forms a cavity, where the at least one wall further has a first end and a second end. The first end can be configured to couple to a terminus of a heat exchanger of the thermal transfer device. The second end can be configured to couple to a collector box of the thermal transfer device. At least a portion of the at least one wall can be disposed in a vestibule of the thermal transfer device. The cavity can be configured to simultaneously receive a first fluid that flows from the first end to the second end and a second fluid that flows from the second end to the first end.

A heat exchanger disposed on a downstream side of a gas flow passage of combustion exhaust gas ejected from a burner comprising a plurality of heat exchange units stacked in a gas flow passage direction of the combustion exhaust gas, an inlet pipe, and an outlet pipe, wherein the inlet pipe and the outlet pipe are provided so as to protrude from a most downstream heat exchange unit located on a most downstream side of the gas flow passage of the combustion exhaust gas toward the downstream side of the gas flow passage of the combustion exhaust gas.

A heat exchanger for a heating device includes a plurality of tubes arranged in a juxtaposed configuration, and at least one first manifold member on the outside of the tubes. Each tube is wound in a spiral having a plurality of substantially co-planar turns including at least one inner turn and at least one further turn around the inner turn. At least one first tube has a first end portion, which extends starting from the inner turn towards the outside of the corresponding spiral, with at least one part of the first end portion that is superimposed on the at least one further turn in a position corresponding to a major face of the spiral, for connection to the at least one first manifold member. The at least one first tube has at least one transverse depression in which a corresponding part of the first end portion is at least partially received.

A fluid heating system for heating a production fluid using a thermal transfer fluid, the production fluid being contained in a vessel includes an electric blower configured to receive ambient air and electrical input power and to provide output source air, a combustion system configured to receive the source air from the electric blower and to receive fuel and to provide the thermal transfer fluid, a heat exchanger configured to receive the thermal transfer fluid from the combustion system and configured to provide heat exchange from the thermal transfer fluid to the production fluid, and to provide output exhaust gas, and wherein the electric fan provides a predetermined volume flow rate of the output source air at a predetermined blower efficiency such that the fluid heating system has a Bulk Heat Flux of at least about 14.7 kBTU/Hr/ft.sup.2 and a Pressure Drop of at least about 0.7 psi.

The present invention relates to a heat exchanger enabling the reduction of the number of components constituting the heat exchanger, the simplification of the coupling structure thereof, and also, the decrease of combustion gas flow resistance and the minimization of noise and vibration generation, the heat exchanger being provided with a heat exchange unit having heating medium flow channels through which a heating medium flows and combustion gas flow channels through which combustion gas combusted in the burner flows to be alternately formed and adjacent to each other in spaces between a plurality of plates, wherein the heat exchange unit comprises: a sensible heat unit which surrounds the outer side of a combustion chamber, is formed of one side area of the plates, and heats the heating medium by using sensible heat of combustion gas generated by the combustion of the burner; and a latent heat unit which is formed of the other side area of the plates, and heats the heating medium by using latent heat of water vapor included in combustion gas that has finished undergoing heat exchange in the sensible heat unit, wherein bent flange units are formed on the edges of the plurality of plates, and in a state where the flange units of neighboring plates overlap, certain areas among the edges of the plurality of plates have formed thereon combustion gas pass-through units having combustion gas flowing through the combustion gas flow channels pass therethrough.

The notched base ring comprises a base ring sheet body including a top portion, a bottom portion, a first end connecting the top portion to the bottom portion, and a second end connecting the bottom portion to the top portion. The top portion includes a plurality of attachment lugs and defines a plurality of notches, each notch being at least partially defined by two lugs disposed on opposite sides of the notch, the top portion also including an angled top edge that is disposed at each of the attachment lugs, and the bottom portion includes a bottom support edge.

A heat exchanger for an apparatus including a burner has at least one tube extending along a centerline from an inlet end adjacent the burner to an outlet end. A plurality of indentations is formed in the tube adjacent the inlet end and extend radially inward towards the centerline. The indentations are formed in opposing pairs extending towards one another to a depth sufficient to create turbulent fluid flow through the inlet end of the tube.

A heat exchanger includes a plurality of heat transfer tubes extending in a first direction and aligned in a second direction intersecting with the first direction, and a plurality of fins disposed in the first direction. The fins each include a plurality of fin main bodies aligned in the second direction, and a bridging portion connecting two adjacent ones of the fin main bodies. At least one of the fin main bodies is provided with a through hole next to the bridging portion in the second direction.