STEAM GENERATOR WITH SPLIT FLOW PREHEATER

摘要

A shell and tube steam generator having a U-shaped or straight tube bundle and a preheater. The preheater is disposed on the cold leg portion of the tube bundle and comprises walls and a plurality of baffles which cooperate to cause the feedwater entering the preheater to split and follow two flow paths, one in a generally upward direction and the other in a generally downward direction. The preheater has an outlet disposed to cause the fluid flowing therefrom to flow across the tube sheet and then upwardly along the outside surface of the tubes to optimize the temperature and pressure of the steam produced and to eliminate the channeling of cold fluid along the tubes which causes thermal stresses and shock on the tube sheet and lower shell.