Method of joining tube and tube sheet in shell & tube heat exchanger

Abstract

A method of joining tubes that are regularly arranged in a shell & tube heat exchanger to tube sheets placed at opposite ends of the tubes and a shell & tube heat exchanger produced by the method. The method of joining the tubes to the tube sheets includes: forming a tube sheet groove in a surface of the tube sheet at a location spaced apart from a tube insert hole of the tube sheet by a predetermined distance, and forming a tube holding groove in an inner surface of the tube insert hole; inserting the tube into the tube insert hole of the tube sheet and expanding the tube; and performing both tube side welding and shell side welding so as to join the tube to the tube sheet.

What is claimed is: 
     
         1 . A method of joining a tube and a tube sheet in a shell & tube heat exchanger, comprising:
 forming a tube sheet groove in a surface of the tube sheet at a location spaced apart from a tube insert hole of the tube sheet by a predetermined distance, and forming a tube holding groove in an inner surface of the tube insert hole; 
 inserting the tube into the tube insert hole of the tube sheet and expanding the tube; and 
 performing both tube side welding and shell side welding so as to join the tube to the tube sheet. 
 
     
     
         2 . The method as set forth in  claim 1 , wherein a thickness of a welding portion formed in the tube sheet by the tube sheet groove is equal to a thickness of the tube. 
     
     
         3 . The method as set forth in  claim 1 , wherein the tube sheet groove has a ring shape. 
     
     
         4 . The method as set forth in  claim 1 , wherein the tube holding groove has a ring shape. 
     
     
         5 . The method as set forth in  claim 1 , wherein the shell side welding is performed by forming a welding torch in the outside surface of the tube.