GB828680A - Improvements in heat exchangers - Google Patents

Abstract

828,680. Tubular heat exchangers. FOSTER WHEELER Ltd. March 20, 1958 [March 20, 1957], No. 8963/58. Class 64(3) In a shell and tube type heat exchanger in which a fluid flowing through vertical tubes 18 carried by a tube sheet 14 at the lower end of the shell 12 is heated by a superheated vapour flowing over the tubes, partitions (e.g. 27, 28, 30, 35, 36) define a space 42 containing part of the tube bundle and are supported (e.g. by a plate 31) so as to permit expansion and contraction without contacting the tube sheet, the arrangement being that superheated vapour is admitted to the space 42 and is cooled by contact with the tubes therein before being discharged through an outlet 44 into the shell space where, after flowing over the remaining tube surface it is discharged as condensate through an outlet 56. In the form shown, feed water flows from an inlet 19 through the tubes 18 to an outlet 20 and is heated by steam flowing over the tubes. The steam condensate produced in the upper part of the shell, after the steam has been desuperheated in space 42, collects in a space 55 defined in part by a partition 25, the flow of condensate through outlet 56 being so controlled by any conventional means as to keep constant the liquid level in space 55. In a modification the partition 25 does not extend to and in contact with the tube sheet 14 so that condensate collects on both sides of the partition, the level of condensate being maintained below the bottom plate 36 of the desuperheating zone 42 and above the lower edge of the partition 25.