STEAM GENERATOR WITH SPLIT FLOW PREHEATER

摘要

1413231 Steam generators with preheaters WESTINGHOUSE ELECTRIC CORP 11 July 1973 [24 July 1972] 33021/73 Heading F4A A steam generator, of the type in which a heating fluid passes through U-tubes 3 between inlet and outlet chambers 17 and 19 and feedwater enters at 27, is provided with a preheater 31 at the lower end of those legs of the tubes 3 that carry heating fluid to the outlet chamber 19 (see Fig. 2) which has an arrangement of baffles which directs the water along two courses -upward and downward over tube sheet 13 and the baffles are arranged so that approximately 70% of the water takes the upward course. In the embodiment shown steam separators are arranged in the upper portion of the generator and separated water is reurned through annular space 43 to mix with the feedwater emerging from the lower end of the preheater; a baffle 45 prevents direct impingement of feedwater against the U-tubes 3. In another embodiment (Figs. 3-6, not shown) a central partition is provided between the legs of the tubes 3 and steam passes downwardly to be superheated before leaving an outlet situated opposite the inlet 27. A further embodiment (Figs. 6-8, not shown) is similar but the dividing partition is moved to midway among the legs of the tubes 3 which carry heating fluid upward from the inlet chamber 17. Reference has been directed by the Comptroller to Specification 1,341,934.