Method for attaching a tube to a workpiece

A method of attaching a metal tube having a tube wall defining a tube channel therein to a metal workpiece having a workpiece wall, the method comprising the steps of:

• (a) forming a workpiece opening in the workpiece wall, the workpiece opening being at least partially defined by a workpiece opening wall surface in the workpiece wall;
• (b) forming a tube engagement surface on the tube wall that is formed for engagement with the workpiece opening wall surface;
• (c) positioning at least one heating element in a predetermined position relative to the workpiece opening wall surface and the tube engagement surface;
• (d) energizing said at least one heating element in a non-oxidizing atmosphere;
• (e) with said at least one energized heating element, in the non-oxidizing atmosphere, heating a workpiece heated portion that extends into the workpiece wall from the workpiece opening wall surface to a hot working temperature, at which the workpiece heated portion is at least partially plastically deformable;
• (f) with said at least one energized heating element, in the non-oxidizing atmosphere, heating a tube heated portion that extends into the tube wall from the tube engagement surface to the hot working temperature, at which the tube heated portion is at least partially plastically deformable;
• (g) while said workpiece heated portion and said tube heated portion are at the hot working temperature, subjecting the tube to an engagement motion, to move the tube engagement surface relative to the workpiece opening wall surface;
• (h) while the tube is subjected to the engagement motion, and while said workpiece heated portion and said tube heated portion are at the hot working temperature, subjecting the tube to a translocation motion, to push the tube engagement surface against the workpiece opening wall surface while the tube is subjected to the engagement motion;
• (i) while the tube is subjected to the engagement motion, and while said tube heated portion and said workpiece heated portion are at the hot working temperature, pressing the tube engagement surface against the workpiece opening wall surface, to cause plastic deformation of said workpiece heated portion and of said tube heated portion as they engage each other, for creating a metallic bond between the tube and the workpiece;
• and
• (j) allowing the tube and the workpiece to cool, to bond the tube and the workpiece together.