Abstract:
A process by which the end (16) of a tube (10) having at least one internal surface feature (12) is reduced and at least a portion of the surface feature eliminated from the tube end while achieving accurate control of the outer diameter of the tube end. The process preferably makes use of a forming tool comprising an external die (24) for reducing the outer diameter of a tube and a mandrel (26) for deforming the internal passage of the tube. The process generally comprises forcing the external die (24) over the end of the tube so that the outer diameter of the tube end is reduced and so that the mandrel (26) is simultaneously inserted through the internal passage of the tube end. While the tube end (16) remains within the external die (24), the mandrel (26) is withdrawn from the internal passage of the tube end to eliminate the internal surface feature (12).
Abstract:
An internally grooved heat exchanger pipe wherein the inner surface is divided into a plurality of regions (W1, W2) continuous in the direction of the axis of the pipe, (L), and the adjoining regions (W1, W2) are formed with a number of fins (10, 11) that differ in at least one of such factors as the lead angles ( theta , theta ') with respect to the direction of the axis of the pipe, (L), fin top angles ( alpha , alpha ') and fin pitches (p, p'), the boundary line (a) between adjoining regions (W1, W2) being sinuous in the direction of the axis of the pipe, (L). A metal bar working roll wherein a plurality of roll pieces (2a, 2b) having a number of grooves (20, 21) formed in the outer peripheral surface are combined such that they are axially stacked, the contact surface (c) between adjoining roll pieces (2a, 2b) being an inclined surface.
Abstract:
An internally grooved heat exchanger pipe wherein the inner surface is divided into a plurality of regions (W1, W2) continuous in the direction of the axis of the pipe, (L), and the adjoining regions (W1, W2) are formed with a number of fins (10, 11) that differ in at least one of such factors as the lead angles ( theta , theta ') with respect to the direction of the axis of the pipe, (L), fin top angles ( alpha , alpha ') and fin pitches (p, p'), the boundary line (a) between adjoining regions (W1, W2) being sinuous in the direction of the axis of the pipe, (L). A metal bar working roll wherein a plurality of roll pieces (2a, 2b) having a number of grooves (20, 21) formed in the outer peripheral surface are combined such that they are axially stacked, the contact surface (c) between adjoining roll pieces (2a, 2b) being an inclined surface.
Abstract:
A heat exchanger including a header having a plurality of header openings with rigid tubes that may be made of plastic are inserted in the openings. The tubes are sealed to the header to prevent leakage between the header and the tubes to prevent water and air leakage between the wet, scavenger air stream flowing through the tubes and a dry air stream flowing around the tubes. A method of making the heat exchanger includes providing the openings with a flange and uses an interference fit between the rigid heat exchange tubes and the header openings. A self-leveling sealant may be used to seal the heat exchanger tubes to the header using, for example, a paint roller and/or a paint sprayer.
Abstract:
The present invention relates to a tube (1) made of a profile rolled metal product, in particular for use in heat exchangers, a rolled metal product and a method of producing the same. The tube (1) includes a first wall (2) and a second wall (4) forming two opposing sides of the tube, and a plurality of reinforcing structures connecting the first and second walls (2, 4) and forming longitudinal passages (10) between them. Each reinforcing structure is formed by a longitudinal ridge (6) on the first wall (2) projecting towards the second wall (4) and a longitudinal ridge (8) on the second wall (4) protecting towards the first wall (2). The ridges (6, 8) are joined to each other at their sides.
Abstract:
A machine (20) may produce a tube (28) having textured internal and external surfaces (22, 24) in a single operation. Inner (36) and outer knurling tools (42) may form the textured surfaces. The texturing of the internal and external surfaces (22, 24) may be helical patterns of ribs (32) and grooves (30). The height of the ribs (32) formed in the internal and external surfaces (22, 24) may be less than about 35 mils. The angles of the patterns relative to a longitudinal axis of the tube (28) may be less than about 45 DEG . The angle of the helical pattern allows textured tubes (28) to be used as heat exchanger elements wherein flow is directed substantially coaxial to the longitudinal axes of the tubes. The helical pattern formed in the external surface (24) may be oriented in a right hand or left hand helical orientation. Similarly, the helical pattern formed in the internal surface (22) may be oriented in a right hand or left hand orientation.
Abstract:
A process by which the end (16) of a tube (10) having at least one internal surface feature (12) is reduced and at least a portion of the surface feature eliminated from the tube end while achieving accurate control of the outer diameter of the tube end. The process preferably makes use of a forming tool comprising an external die (24) for reducing the outer diameter of a tube and a mandrel (26) for deforming the internal passage of the tube. The process generally comprises forcing the external die (24) over the end of the tube so that the outer diameter of the tube end is reduced and so that the mandrel (26) is simultaneously inserted through the internal passage of the tube end. While the tube end (16) remains within the external die (24), the mandrel (26) is withdrawn from the internal passage of the tube end to eliminate the internal surface feature (12).
Abstract:
Process for making micro-multiport tubing for use in automobile air conditioner heat exchangers whereby the tubing is a flat body with a row of side-by-side passageways, which are separated by upright extruded webs. Processing of this tubing involves extrusion, a straightening and cutting operation, assembly and furnace brazing of the condenser. The webs are extruded so that they have a reduced thickness at their centers. In response to successive cold working of the body, the webs are changed in shape to a more uniform thickness state.