METHOD FOR JOINING THE TUBE AND THE TUBE SHEET IN SHELL AND TUBE EXCHANGER

摘要

The present invention relates to a shell and tube heat exchanger. A method for joining a tube sheet and a tube of a shell and tube heat exchanger comprises: a step for forming a filler metal part serving as filler metal by welding a welding material including molybdenum to the surface of a tube sheet; a step for correcting the tube sheet which has been deformed by the welding; a step for machining the filler metal part so as to maintain the plane surface thereof; a step for processing a plurality of tube holes for inserting a tube into the tube sheet; a step for forming tube sheet grooves on the side surface of the tube sheet at portions coming into contact with the fluid introduced or discharged with respect to a shell side so as to be spaced from the tube hole inserted by the tube by a predetermined distance, and forming tube grooves on the inner surface of the tube hole; a step for inserting the tube into the tube hole of the tube sheet and expanding the tube; and a step for carrying out tube side welding for the joining of the tube and the tube sheet with respect to a portion coming into contact with the fluid introduced or discharged with respect to the tube side and the shell side welding for the joining of the tube and the tube sheet with respect to the portion coming into contact with the fluid introduced or discharged with respect to the shell side, wherein the tube side welding and the shell side welding are carried out by torch welding for melting the parent metal so as to join the same and the shell side welding is carried out by inserting a welding torch into the tube and melting the parent metal.