Carrier Corporation

Daniel P Gaffaney

Steven J Spencer

Amer F Ali

Kenneth P Gray

Neelkanth S Gupte

Robert H Chiang

Michael P McCabe

Xin Liu

Bruce J Poplawski

Thomas J Garosshen

Ross A Moyer

Donald L Bennett

Edward G Rottmann

Sandra Jayne Downey

Albert J Kallfelz

Michael L McDonough

Robert H Zimmerli

Robert H L Chiang

Hannu Tapani Heiskanen

Gerald Lee Riggs

James Marvin Satterly

A heat exchanger fin collar for a plate-fin heat exchanger having close tolerance dimensions for achieving greater contact area on the tube. The fin collar comprises an elongated fin portion for dissipating heat and a leg connected with the fin portion. The leg has a height and includes a straight contact portion substantially perpendicular to the fin portion, wherein the contact portion has a contact height along which the contact portion contacts the tube. The height is in the range of 0.008 to 0.080 inches. It also includes a first curved end portion having a first radius extending from a first end of the contact portion and a stepped transitional portion connecting the contact portion and the elongated fin portion. The transitional portion has a second curved end portion having a second radius, wherein the second curved end portion extends from the contact portion opposite the first end. A method for forming the fin collar and a heat exchanger are also disclosed.

Fin collar and method of manufacturing

An article having a first member formed from a first metal and a second member connected with the first member at a contact area. The second member is formed from a second metal having high reduction reaction kinetics and galvanic corrosion driving force relative the first member, wherein the second metal is more noble than the first metal. A material for substantially eliminating the galvanic corrosion problem by reducing the reduction reaction kinetics of the second metal in the presence of an electrolyte is provided between the first and second metals. In a preferred embodiment, the article is a heat exchanger wherein the first member is a fin collar and the second member a tube and the material for reducing is a coating on the tube has low reduction reaction kinetics relative to copper for reducing corrosion activities between the tube and fin collar.

Article exhibiting improved resistance to galvanic corrosion

A method for forming an heat exchanger fin collar for a plate-fin heat exchanger having close tolerance dimensions for achieving greater contact area on the tube. The fin collar includes an elongated fin portion for dissipating heat and a leg connected with the fin portion. The leg has a height and includes a straight contact portion substantially perpendicular to the fin portion, wherein the contact portion has a contact height along which the contact portion contacts the tube. The height is in the range of 0.008 to 0.080 inches. It also includes a first curved end portion having a first radius extending from a first end of the contact portion and a stepped transitional portion connecting the contact portion and the elongated fin portion. The transitional portion has a second curved end portion having a second radius, wherein the second curved end portion extends from the contact portion opposite the first end.

A heat transfer tube (,) for use in an application, such as a shell and tube type air conditioning system condenser, in which a fluid flowing through the heat exchanger external to the tubes condenses by transfer of heat to a cooling fluid flowing through the tubes. The tube has at least one fin convolution (,) extending helically around its external surface (,). A pattern of notches (,) extends at an oblique angle (&agr;) across the fin convolutions at intervals about the circumference of the tube. There is a spike (,) between each pair of adjacent notches. The fin convolution, notches and spikes are formed in the tube by rolling the wall of the tube between a mandrel and, first, a gang of finning disks (,) and, second, a notching wheel (,). Because, during the manufacture of the tube, of the interaction of the rotating and advancing tube and the notching wheel, the angle (&bgr;) of inclination of the axis of the tip of the spike is oblique with respect to the notch angle. The maximum width (W,) of the spike is greater than the width (W,) of the proximal portion of the fin convolution.

Heat transfer tube

A heat transfer tube having an internal surface that enhances the heat transfer performance of and also improves the workability of the tube and a method of manufacturing such a tube. The internal surface has a plurality of ribs that extend at an angle to the longitudinal axis of the tube. A pattern of parallel notches, extending at an angle to the ribs, extend through the ribs and into the main inner surface of the tube wall. The tube can be made by rolling embossing the pattern of ribs and notches on to one side of a flat metal strip, then roll forming the strip into a tubular shape with the embossed pattern on the interior of the tubular shape and the edges of the strip forming a longitudinal seam, then joining, preferably by welding, the edges along the longitudinal seam to form a tube. In a preferred embodiment, the notches in the inner surface extend into the weld zone of the tube. The pattern of ribs and notches increase the total internal surface area of the tube and also promote conditions for the flow of refrigerant within the tube that increase heat transfer performance. The notches also serve to inhibit the propagation of splits in the tube wall when the tube is flared.

A method for treating heat exchanger tubing to be expanded by fluidic or electromagnetic expansion. The tubing treatment reduces the increased material hardness of the tubing in areas where cold work has been imparted thereon. By reducing these areas which have increased material hardness, the tubing will have a substantially similar tube yield along its entire length and can therefore be expanded to substantially the same cross-sectional area throughout by either fluidic or electromagnetic expansion. After forming the cold work regions, the regions are annealed with a heat source, such as through flame or induction heating, and are gradually cooled to avoid the effects of quenching.

Method for manufacturing heat exchangers to allow uniform expansion of

A method of manufacturing a heat exchanger using fluidic expansion, the heat exchanger having tubing sections interconnected to form at least one circuit for transporting a first heat transfer fluid and conductive fins secured to the circuit for increasing the surface area thereof and increasing the heat transfer between the first fluid and a second fluid flowing among the fins. The tubing sections are positioned in a predetermined manner and the fins are disposed therewith and along the length thereof. The inlets and outlets of the tubing sections are then interconnected to form said the fluid circuit. Next, the fins are secured in place so as not become damaged during the sealing of the interconnections, which follows immediately thereafter. Finally, the entire circuit is expanded to enmesh said fins by enclosing the volume of the circuit and introducing an expansion fluid therein at a pressure which surpasses the tube yield strength of the tubing and causes the walls thereof to expand radially outward.

Method for constructing heat exchangers using fluidic expansion

An apparatus for expanding the tubes in a heat exchanger of the plate fin and tube type. The expander is of the type that expands the tubes by driving a 'bullet' through the tube with the bullet being attached to and driven by an expander or bullet rod. The apparatus has a sensor positioned so as to be able to measure the compressive force on the expander rod. The output of the sensor is proportional to the force exerted on the rod and can be used to provide an alarm or safety shutdown of the apparatus upon the sensing of excessive force on the expander rod. The sensor output can also be used for quality and process control.

Tube expander with force sensor

A tube for use in a heat exchanger where heat is transferred between a fluid flowing through the tube and a fluid flowing around the exterior of the tube and where the fluid external to the tube boils during the heat exchange process. The tube has one or more external fin convolutions extending from its external surface. At intervals along each side surface of the fin convolutions there are shoulder notches extending from the fin side surfaces. The groove space between adjacent fin convolutions has raised teeth located circumferentially at intervals. The fin convolutions do not extend perpendicularly from the tube surface but are inclined, with one convolution overlying an adjacent groove but not touching its adjacent neighbor fin convolution to form a re-entrant boiling cavity with an opening gap. In one embodiment, the opening gap extends completely around the circumference of the tube. In another embodiment, the curved fin convolutions are depressed at intervals around the circumference of the tube so that a fin convolution is in close proximity to its adjacent neighbor closing the gap in the vicinity of the depression.

Heat exchanger tube

A heat exchanger tube (10) for use in an application, such as a shell and tube type air conditioning system condenser, in which a fluid flowing through the heat exchanger external to the tubes condenses by transfer of heat to a cooling fluid flowing through the tubes. The tube has at least one fin convolution (22) extending helically around its external surface (13). Multiple axial notches (23) are impressed into the fin at intervals along its extent. Because the notches are impressed and not cut into the fin, material displaced from a fin to form a notch forms lateral projections (24) from the the walls of the fin. The notched fins provide increased external heat transfer surface area on the tube, destabilize the film of condensate on the tube external surface, thus causing the film to be generally thinner, and promote condensate drainage from the fins and off the tube and thus increase the heat transfer performance of the tube.

A filter system for protecting a heat exchange coil from corrosive constituents carried by an air stream which is passed through the heat exchange coil includes a flexible filter for removing the corrosive constituents from the air stream prior to its engaging with the coil. A net like spacer is located between the coil and the flexible filter for supporting the flexible filter in a predetermined spaced relationship with the heat exchange coil.

Corrosion protection filter for heat exchangers

A single-station tube expander apparatus bells and expands the open ends of heat exchanger hairpin tubes in a plate-fin heat exchanger unit. A frame supports belling jaw fingers which close over and the open ends of the tubes so that a belling device can enter the tube ends to urge the tube outward into a profile surface formed in the mating faces of the fingers. Also on the frame are mounted expander jaw fingers which close over tube ends which have been belled previously, and hold the associated hairpin tubes against axial movement while expander rods pass into the associated tube legs to urge the hairpin tube legs outward to contact against the fin plates and tube sheets of the fin pack heat exchanger. The belling fingers and belling device move step by step from one tube to another, and the expander gripping fingers and expander rods follow the belling fingers and belling device.

Growing community of inventors

Chittenango, NY, United States of America

Daniel P Gaffaney