Abstract: A gas supply manifold has a nozzle forming member having a plurality of gas injection nozzles, a cover member configured to be overlapped on the nozzle forming member, and a caulking-fastening portion configured to fasten the nozzle forming member and the cover member. The caulking-fastening portion is configured such that a convex portion provided for one of the nozzle forming member and the cover member penetrates a hole provided for the other member, and a tip end portion of the convex portion has an engagement portion, the engagement portion having a larger diameter or a larger width than the hole and being engaged with a peripheral edge portion of the hole. A tip end face of the convex portion has a dent portion formed by pressing the tip end face into a base portion side of the convex portion and an area around the dent portion constitutes the engagement portion. Thus, the nozzle forming member and the cover member are appropriately caulked and fastened.

Abstract: A header of a heat exchanger including a first wall connected with a plurality of heat transfer tubes of the heat exchanger, a second wall facing the first wall with an interval therebetween, and a circumferential wall connecting outer circumferential edges of the first and the second walls in such a manner that an area between the first and the second walls constitutes a chamber for inflow of fluid, the chamber communicating with each of the heat transfer tube. At least one of the first and the second walls is configured to curve in such a manner that a central area of the wall is positioned close to an inside of the chamber than an outer circumferential area of the wall. The thickness of the header is reduced and enough strength of the header is obtained, thereby preferably enduring repeating water hammer.

Abstract: The heat exchanger wherein each end of a plurality of heat transfer tubes is connected to an end wall of a bulging portion provided at a side wall of a case, an open edge of a header is fitted onto the bulging portion, and a chamber connecting with each heat transfer tube is formed. For jointing the header to the side wall, an inner circumferential end of the open edge of the header is formed as a first curved surface with a convex section, an outer face of the circumferential wall of the bulging portion is formed as a second curved surface with a concave section, the first curved surface and the second curved surface contact each other, and the surface-contact portion and the area therearound are welded. The number of the members is reduced, the structure is simplified, and the production cost of the heat exchanger is reduced.

Abstract: The heat exchanger HE comprising a case 2 housing a plurality of heat transfer tubes 1 and a header 3 having a hollow main body 30 with an open edge 33. A side wall 21 of the case 2 is provided with a bulging portion 22 having a cylindrical circumferential wall 22a bulging out of the case 2 and an end wall 22b which blocks a tip portion of the circumferential wall 22a. Each end of the heat transfer tubes 1 is inserted into a penetrating hole 22c provided for the end wall 22b of the bulging portion 22, and is jointed to the end wall 22b, and the open edge 33 of the header 3 is fitted onto the circumferential wall 22a of the bulging portion 22, thereby forming a chamber 36 communicating with the inside of each heat transfer tube 1. Therefore, it is possible that the number of the members of the heat exchanger HE is reduced, the configuration is simplified, and the heat exchanger HE is easily manufactured at low cost.