GB261762A - Improvements in and relating to liquid boilers - Google Patents

Abstract

261,762. British Thomson-Houston Co., Ltd., (Assignees of Emmet, W. Le R., and Coulson, B. P.). Nov. 18, 1925, [Convention date]. V a p o u r engines. - A vapour generator, particularly for vaporizing high boiling point, heavy liquid such as mercury, comprises a number of units 4 suspended side by side in a furnace 1 and receiving liquid from a common header 35, vapour being delivered to a common header or drum 5. Each unit includes a casing 9 secured to a tube plate 8 from which depends a number of tubes each comprising an outer tube 15 and an inner core 16 of the same contour as the outer tube. the intermediate space communicating with the lower end of a passage 22 through the core. The cores which float on the liquid in the tubes may consist of tubes 23, 24, welded together at top and ,bottom the inner tube 24 being bent to provide for unequal expansion. Spaced from the tube plate 8 is a baffle 25 with openings 27 directing liquid into the funnel-shaped upper ends of the core passages 22. Vapour generated in the tubes rises in upwardly widening channels formed by ribs 21 on the cores and is kept separate from incoming liquid by the baffle 25 against recesses 28 of which the cores are held by the buoyancy of the liquid. Its direction is further changed by a baffle 13. Superheating pipes 38 extending from the front ends of the unit to a rear conduit 39 convey vapour to the drum 5. A number of blocks 29 are spaced by strips 30, 31, from the baffle 25 and serve to decrease the quantity of liquid necessary to provide the required depth of liquid in the unit. A liquid level indicator is connected, for example, to every second unit. The tubes of each unit are flared and in staggered relation and baffles between the groups are provided to distribute the heat equally to all the tubes.