Abstract: An apparatus for forming helically wrapped spine fin heat exchanger tubes is disclosed which includes a rotatable cutter head operable to cut a strip of thin metal to provide a base portion and a multiplicity of spines integrally joined at one end to the base portion. A tube feed is provided to axially feed smooth tubing past the cutter head. As the tube is fed past the cutter head the cutter head operates to helically wind the spine fin material on the tube. A first drive is provided to drive the tube feed and cutter head in time relation to ensure that the tube is fed through a predetermined minimum distance during each revolution of the cutter head. A second drive is provided to increase the distance through which the tube is fed during each revolution of the cutter head to increase the helix angle of the material being wound onto the tube and correspondingly reduce the spine fin density at selected locations along the tube.

Abstract: Apparatus for producing spine fin material of the type employing counter-rotating toothed cutter rolls to transversely slit ribbon stock. The apparatus includes a positive gear drive for controlling the angular cutter roll postions and a support arrangement permitting center-to-center adjustment of the cutter rolls independently of the center-to-center relation of associated gear drive elements.

Abstract: A spine fin heat exchanger is disclosed in which the density of the spine fins is greater along the portions of the passes within the pattern of high flow of air or the like across the heat exchanger. Those portions of the tubing at the bends and outside such pattern are formed with a lower spine fin density. Such lower density outside the patterns and at the bends does not materially reduce the overall heat exchange capacity of the heat exchanger, and results in a heat exchanger where less material and time are required to form the heat exchanger without any significant loss in its capacity. The heat exchanger is preferably formed by changing the rate of feed of the tube as it feeds through the winding head to increase the amount of stretch of the spine fin strip along the zones of low density compared to the amount of stretch in the strip along the zone of high density. Consequently, the same amount of material is required for each wrap along both zones.

Abstract: A spine fin heat exchanger is disclosed in which the density of the spine fins is greater along the portions of the passes within the pattern of high flow of air or the like across the heat exchanger. Those portions of the tubing at the bends and outside such pattern are formed with a lower spine fin density. Such lower density outside the patterns and at the bends does not materially reduce the overall heat exchange capacity of the heat exchanger, and results in a heat exchanger where less material and time are required to form the heat exchanger without any significant loss in its capacity. The heat exchanger is preferably formed by changing the rate of feed of the tube as it feeds through the winding head to increase the amount of stretch of the spine fin strip along the zones of low density compared to the amount of stretch in the strip along the zone of high density. Consequently, the same amount of material is required for each wrap along both zones.