GB513763A - Improvements in, or relating to, furnaces for the heat-treatment of metals - Google Patents

Abstract

513,763. Annealing furnaces. SADLER, A. L. (Keener, S. F.). June 16, 1938, Nos. 17871 and 23019. [Class 51 (ii)] An annealing furnace comprises a worksupporting hearth with side combustion chambers e, e<1> of trough form fired from opposite ends, the flow of gases from which into the heating chamber is controlled by adjustable tiles e<2> spanning the open tops of the chambers The tiles are preferably so adjusted that the distances between them decrease away from the burners. The hearth may be of bogie form, or where, as shown, it is adapted to take a removable hood d, a furnace assembly may comprise a number of hearths b, b<1>, b<2>, each with its own pair of combustion chambers, and with common sand seals g<1>, g<2> between adjacent hearths. In two sides of the hood are vertical flues i, i<1>, which register with connections h<6>, h<7> to hearth flues h<2>, h<3>, and which can be put into communication with the heating chamber through damper-controlled ports i<2>, i<3>. By closing the upper end of flue i on one side and opening its port i<2> heating gases can be drawn downwards to the flue h<2> and exhausted through the opposite flue i. The method of operation may be such that gases flow in opposite directions in the flues h<2>, h<3>.