Patent ID: 9658002
Date: 2017-05-23
CPC Classifications: B23K,F28D,F28F,Y02E,Y10T

Claim:
1. A process of connecting a tube to a tube sheet, comprising: inserting a tube end of the tube into a tube sheet hole of the tube sheet with an interference fit between the tube end and the tube sheet that locks the tube end into the tube sheet without flaring or expanding the tube end adjacent to the tube sheet, wherein the interference fit is created by modifying an exterior surface of the tube, modifying an interior surface of the tube sheet hole, or both modifying the exterior surface of the tube and modifying the interior surface of the tube sheet hole; installing a collar around the tube, and at least partially fitting the collar into the tube sheet hole or into a hole in a baffle that is separate from the tube sheet; and friction stir welding the tube to the tube sheet.