| 摘要 |
PURPOSE:To reduce corrosion hazard, by reducing welded part by making use of deep drawing processing and to eliminate a welded part in a gaseous phase part. CONSTITUTION:A hole 3 is provided on about a central part of a flat surface 2 of the top part of an upset cylinder 1 made of stainless steel formed by deep processing, burring processing 4 is applied to the hole 3, a flue part is formed by caving in a cylindrical form inwardly, holes are provided on the upper part 5 and the lower part 6 of a side wall of the cylinder 1, into which pipes for circulation of hot water are inserted for welding 7. A main body 8 made of a stainless steel plate, whose diameter is smaller than that of the cylinder 1, and a flange part 9, whose diameter is a little larger than that of the cylinder 1 of a base part of the main body 8, are formed by the deep drawing processing, while a hole 11 is provided on the flat surface 10 of the top part of the main body 8, the cylinder 1 and the main body are made into an external cylinder and an internal cylinder respectively, the tip of a caved-in part 4 of the cylinder 1 is inserted into the hole 11 of the main body 8, and the edge of the tip of the caved-in part 4 and the edge of the bottom of the cylinder 1 are welded 12 and 13 with the edge of the hole 11 and the flange part 9 respectively. |
