GB400819A - Improvements in and connected with water tube steam generators - Google Patents

Abstract

400,819. Water-tube steam boilers. BABCOCK & WILCOX, Ltd., Babcock House, Farringdon Street, London.-(Assignees of Kerr, H. J. ; 639, Chestnut Street, Westfield, New Jersey, U.S.A.) Feb. 4, 1933, No. 3499. Convention date, Feb. 20, 1932. [Class 123 (ii).] A high drum water-tube boiler comprises a vertical gas pass, a natural circulation bank of steam generating tubes 4 extending across,the gas pass and connected to the steam drum by uptake and down circulators, and a forced circulation stage 34 through which all the feed water passes arranged in the portion of the gas pass bounded by the tubes 4 and the uptake and downtake circulators. The gas pass is of progressively decreasing area. A superheater 27 is arranged below the forced circulation stage. An economiser 13 and an air heater are arranged in the gas pass above the steam drum. At one side of the boiler the return bend portions of the superheater and forced circulation tubes are of Y form and are supported by plates 14. Removable caps facilitate cleaning. At the opposite side of the boiler the forced circulation tubes are welded to a plate 37 clamped by a member 38 to an uptake circulator. In a modification the downtake circulators are bent inwards and the Y form supports on the forced circulation tubes are replaced by ordinary return bends supported in a similar manner to those on the opposite side. In a further modification, Fig. 9, the forced circulation tubes 34 are secured to the uptake and downtake circulators 2 by means of U-shaped bolts 46, spacing blocks 45, 47, and wall plate 48.