| 摘要 |
1488989 Tubular heat exchangers KRAFTWERK UNION AG 3 Dec 1975 [10 Dec 1974] 49735/75 Heading F4S A heat exchanger comprises a housing 11 containing two tube nests 4, 7 spaced apart by a distance A and connected between a tube plate 3 fixed relative to the housing, and the tube plate 5 of a floating return header 6. In use, steam at one temperature (e.g. from a lower temperature and pressure stage of a turbine) enters the housing at 10 to flow over the tube nest 4, and steam at a higher temperature (e.g. from a higher temperature and pressure stage of the turbine) enters at 13 to flow over the tube nest 7, and the distance A is such as to permit flexing of the tube plate 5 (see Figs. 3 and 4, not shown) to accommodate differential expansion of the two tube nests. As shown, the tube nest 7 is accommodated in a compartment 14 within the housing and defined by walls 15. 12 and 16 are outlets for the steam condensate. The housing 11 is welded to opposed walls 17 of the bled steam flow passage of the turbine. Feedwater to be heated flows through the tube nests 4, 7 in series from an inlet header 2 to an outlet header 8. |
