Multitube type heat exchanger

TLDR: In this paper, the inner diameter of the heat pipe with the hole diameter of a recifying zone in the tube plate was used to prevent a corrosion of a heat pipe mounting part in the feed water heating device for a steam turbine plant.

Abstract: PURPOSE:To prevent a corrosion of a heat pipe mounting part in the feed water heating device for a steam turbine plant and the like, by providing a bell mouth- shaped port and water flow rectifying zone in a tube plate itself, and laser welding the inner diameter of the heat pipe with the hole diameter of the recifying zone in the tube plate. CONSTITUTION:In a water inlet part of the tube plate 4 is provided the bell mouth- shaped port 8. The hole diameter d1 of the feed water rectifying zone 4a and the inner diameter d2 are designed to be the same. The hole diameter d3 of a zone 4b into which the heat pipe 5 is inserted is designed to have the outer diameter d4 of the heat pipe 5. The heat pipe 5 is inserted into the tube plate 4 and then an orientation changing mirror 13 of a laser welding device 11 is inserted up to a junction part 5a, where a laser beam 14 is jetted. After that, the laser beam generator 11 is turned so as to turn a guide tube 12 and the orientation changing mirror 13, so that the tube plate 4 and the heat pipe 5 are welded at the junction part 5a. With such a construction, a rectified water can be supplied to the heat pipe 5 so that any inlet attack which is caused by a turbulent flow of water and which causes a corrosion of the tube can be effectively eliminated.