Abstract: A heat exchanger inner spiral ribbed tube and method of manufacture therefor for use in making a refrigerator condenser or a refrigerator evaporator. The tube has an annular wall having an inner surface. The inner surface has a plurality of inner spiral ribs, each having a spiral angle. The spiral angle is between 0 degrees and 90 degrees; and is 45 degrees in the described embodiment. The tube making method includes the steps of swaging a plain plate between a plain roller and a grooved roller to make a ribbed plate; then forming seam welding the plate at the longitudinal adjacent edges thereof to make the inner spiral ribbed tube.

Abstract: A heat exchanger inner spiral ribbed tube and method of manufacture therefor for use in making a refrigerator condenser or a refrigerator evaporator. The tube has an annular wall having an inner surface. The inner surface has a plurality of inner spiral ribs, each having a spiral angle. The spiral angle is between 0 degrees and 90 degrees; and is 45 degrees in the described embodiment. The tube making method includes the steps of swaging a plain plate between a plain roller and a grooved roller to make a ribbed plate; then seam welding the plate at the longitudinal adjacent edges thereof to make the inner spiral ribbed tube.

Abstract: A finned heat exchange tube is made from a refractory metal such as titanium, titanium alloy, stainless steel, and iron-nickel alloy containing more than 10% nickel, by rolling into the outer surface of a tube of said metal integral fins having a low fin height of less than 0.045 inch (preferably less than 0.033 inch in titanium and less than 0.045 inch for stainless and the iron-nickel alloys), a high fin density of at least 26 fins per inch of tube length (preferably from 27 to 30 fins per inch), and a high fin surface area per unit length of tube which is at least 2.4 times greater than the comparable surface area of the tube prior to finning. The thickness of the tube wall underneath the finned area preferably is made less than the height of the fins.

Abstract: A finned heat exchange tube is made from a refractory metal such as titanium, titanium alloy, stainless steel, and iron-nickel alloy containing more than 10% nickel, by rolling into the outer surface of a tube of said metal integral fins having a low fin height of less than 0.045 inch (preferably less than 0.033 inch in titanium and less than 0.045 inch for stainless and the iron-nickel alloys), a high fin density of at least 26 fins per inch of tube length (preferably from 27 to 30 fins per inch), and a high fin surface area per unit length of tube which is at least 2.4 times greater than the comparable surface area of the tube prior to finning. The thickness of the tube wall underneath the finned area preferably is made less than the height of the fins.