GB390570A - Improvements in or relating to the heat treatment of metal articles and apparatus therefor - Google Patents

Abstract

390,570. Annealing. WELLMAN SMITH OWEN ENGINEERING CORPORATION, Ltd. and WEBB, A. W. OGILVY-, Victoria Station House, Victoria Street, London. Dec. 5, 1931, No. 33810. [Class 72.] In apparatus for annealing metal articles comprising a heating chamber 1 and a cooling chamber 3, waste gases are withdrawn from the chamber 1 at 13, cooled to any desired temperature in a device 21, and re-introduced by a fan 25 at points 33, 35 adjacent the junction of the heating and cooling chambers. The cooled gases delivered at 33 are preferably directed downwardly on to the articles, while those entering at 35 pass upwardly through the conveyer 7. An additional supply of waste gases is drawn by the fan 25 through a pipe 51 into the cooler 21 from a point 55 located towards the cooler end of the chamber 3, a valve in the withdrawal conduit 13 being preferably so set that the amount of gases withdrawn at 13 is only sufficient to make good leakage losses. To prevent entry of air through the outlet end 5 of the cooling chamber, a portion of the cooled gases is delivered through a pipe 29 to nozzles 43, 45 arranged respectively above and below the conveyer 7. The cooler comprises a chamber 21 fitted with a vertical baffle 31, Fig. 4, and pipes 23 through which cooling medium is passed, an outlet being provided for the removal of condensed moisture.