GB289121A - - Google Patents

Abstract

289,121. Beeston, W. G. Jan. 15, 1927. Annealing-furnaces: muffle furnaces; charges, conveying and cooling.-In a furnace for annealing metal sheets in an inert atmosphere, of the kind in which the sheets 11<a> are carried by a conveyer 9 through a muffle - heated chamber 6 and then through a cooling extension 1, the chamber 6 and a superposed heating flue 5 are enclosed in a metal tube 1<a> lined with refractory material 2 and connected to the extension 1 at 1<c>. The flue 5 receives, at one end, hot gases from a gas or coal fired furnace 3 through a lateral passage 4, and communicates at the other end with a chimney 7. The space 8 below the muf33e 6 forms, with a similar space in the lower part of the extension 1, a continuous passage for the return run of the conveyer 9, a non-oxidizing atmosphere, at a pressure slightly above atmospheric, being maintained both in this passage and in the muffle 6. The cooling is effected by a water jacket 10 which is connected to a cooling plant by pipes 11 serving to support the upper run of the conveyer. Where gas firing is used the jacket 10 may be utilized to heat air for combustion. The ends of the furnace are fitted with hoods to which are attached the driving means for the conveyer and feeding and discharging rollers 14, 15.