Abstract: The invention is a cold rolling process which converts rods of hot rolled metal into strips with width to thickness ratios as high as approximately 17 to 1. The process cools the rod between successive rolling mills and employs feed backward tension controls to direct the speed of each individual upline rolling mill in order to reduce the thermal and mechanical shock experienced by the rod as it is flattened into a strip.

Abstract: A finned tube comprising a tube and a texturized solid fin attached thereto, the fin having a proximal edge and an opposite distal edge, the proximal edge being attached helically to the tube so the fin extends outwardly from the tube, the fin having two opposite faces extending from the proximal edge to the distal edge, the two faces of the fin being texturized by regular, small female impressions. In one embodiment the fin is texturized at a location between a fin material supply station and the point of attachment of the fin to the tube. In another embodiment, the fin is texturized at the fin attachment station.

Abstract: A laser beam is directed toward a rotating metallic tube having a fin helically wound about and welded to its surface by a high frequency welding process. The laser beam generates heat in the tube to supplement the heat induced by resistance to electrical current flow to create a proper temperature in the tube for forge welding of the fin and tube.

Abstract: The present invention is based upon the recognition that three different zones of heat transfer conditions exist on a finned tube:1. The upstream zone (portion) of the finned tube that is initially exposed to the fluid flowing from a given location;2. Zones that include the areas on opposite sides of the finned tube where the fluid flows around the finned tube and across (through) the fins; and3. A zone that is located on the trailing edge of the finned tube (opposite from the first zone).The invention recognizes that the fluid flowing conditions (temperature, pressure and velocity) are different at each of the three zones. Because of this difference the invention is the use of a different fin configuration and/or geometry in each of the zones that are conducive to the heat transfer for the fluid flow condition encountered at each zone, thus increasing the heat transfer capability of the fins.

Abstract: The present invention is an enhanced type of fin for making an enhanced serrated finned tube for use in heat exchange applications. The segments, which are formed on the fin when the fin is serrated, are enhanced either prior to serration or after serration. The enhancement consists of impressing, cutting or otherwise providing indentations into the segments, thus broadening the segments, increasing their surface area, and increasing their heat transfer capability.