Heat-exchanger with high-pressure fluid on shell side - has tubes welded into thin tube plates held between plates thick enough to resist press

摘要

A heat exchanger transferring heat between a first fluid at high pressure and a second fluid at a lower pressure than the first comprises an outer shell consisting of a side wall, a cover and a base. The side wall contains an inlet and an outlet for the first fluid. The cover and the base are fitted with water or steam boxes for the second fluid, a number of heat transfer tubes forming a bundle within the outer shell. The heat exchanger includes a first and a second mechanical block integral with the cover and the base respectively. Each block consists of a tube plate of reduced thickness provided with a thicker annulus and a number of holes in each of which is welded, over the whole thickness of the plate, one of the ends of the tubes. Seals ensure fluid-tightness between the annulus and the cover or the base. A tightening plate contg. holes through which the tubes pass freely holds the tube plate against the cover or the base. There are means of fixing the tightening plate on the cover or the base, the cover or the base being supplied with holes in line with end of each tube and opening into the water box or the steam box, as well as a housing within which the tube plate is borne. The structure is adaptable partic. well to pressure conditions, e.g. in steam generators in a nuclear reactor.