GB250201A - Improvements in or relating to the annealing of glassware - Google Patents

Abstract

250,201. Hartford-Empire Co., (Assignees of Mulholland, V.). March 31, 1925, [Convention date]. Glass-annealing l e e r s ; tunnel furnaces; muffle furnaces; charging and discharging; air, supplying; casings and walls; expansion fittings. - A tunnel leer for annealing glassware is provided with heating flues C extending beneath the whole length of the floor and with cooling flues D, incorporated in the roof structure and extending from the discharge end for about two-thirds of the length of the tunnel, the temperature gradient in these flues being adjusted by admitting air, for diluting the heating gases, through one or more of the spaced inlets 55 and by withdrawing the cooling air from flues D through one or more of the spaced outlets 50 which deliver into a common conduit 49. The pipes 50, 55 are fitted with dampers 51, 56, and a motor-driven fan 41, communicating with a box 42 which is connected to the conduit 49 and by vertical passages with the heating flues C, is provided for drawing the hot gases and cooling air through their respective flues at subatmospheric pressure. The tunnel A is built up of metal sections bolted together, the front section being secured at 8 to a box 9 forming an extension of the combustion chamber B and the remaining sections being supported, to permit longitudinal expansion, by rollers 12 which rest on rails 13 secured to the main girders 1. The framework 1, 2 is adjustably mounted on vertical pillars 3 and is so disposed that the tunnel inclines slightly from the hotter to the cooler end. The heating and cooling flues C, D are constituted by cells 7, 19, Fig. 3, formed integral with the floors 4 and roofs 6 of the tunnel sections, the sides 5 of which are secured by spacing-bolts 65 to an outer casing 64 having expansion joints 67 and between which and the tunnel is disposed heat-insulating material 61 such as powdered kieselguhr. The combustion chamber B is fired by a burner 20 and the hot gases, after traversing a box 36 to which air is admitted through pipes 38, enter the box 9 fitted with a regulating damper 40. The ware is carried through the leer on a flexible openwork conveyer G supported directly on the floor 4 and driven by mechanism H; at the discharge end of the leer the conveyer passes over a sorting- table F comprising two side members 69 connected by a number of transverse anti-friction rollers 71.