GB272718A - Improvements in metal heating furnaces - Google Patents

Abstract

272,718. Jeffrey, G. July 13, 1926. Metal-heating furnaces; air and gas heating furnaces.-In a furnace for the treatment of iron articles to render them rustless, such as is described in Specification 15191/98, the air and steam heating tubes are walled within a structure to prevent the hot waste gases impinging upon them. Furnaces 2 are arranged along the outer wall of the treatment chamber 3 and the hot gases after passing over the upper edges 4<a> of partitions 4 pass downwards to a flue 6 and rise through a space 7 into the chamber 3. After acting upon the articles in the chamber the gases escape at 7<a>, pass through flues 8 and circulate in spaces 9, 9<a> around the structure 10 within which the air and steam tubes 12, 12<a> are situated, escaping at 11 to the chimney. The walls w of the structure 10 entirely enclose the tubes 12, which are supported by inner walls a. Air is admitted to the tubes 12<a> through a door d' until the fire has burnt up, the door is then closed and steam is admitted to the space d, through a pipe 14, the heated steam passing from the tubes into a space 6 from which it is led to a space 15 beneath the chamber 3, whence it passes through openings 16 to mix with the smoke gases from the furnaces 2. Openings 17 are provided for cleaning the flues 8.