| 摘要 |
An apparatus for the continuous porcelain enameling of sheet ware including the combination, in succession, of a drying zone for the incoming ware either integral or separate, a pre-heating zone for the ware following the drying zone, a heating zone for the ware after the pre-heating zone or zones, in which the porcelain enamel coating is fused onto the surface, and a cooling zone or zones. Burner means are provided for introducing hot combustion gases into a serpentine tube radiant heater which is in the heating zone to heat the ware by means of flameless radiation. After leaving the heating zone, the hot combustion gases are directed into the final pre-heating zone where they transfer some of their heat to the ware passing through that zone. Finally, the combustion gases leaving the pre-heating zone are directed into the drying zone where they transfer heat by convection to remove moisture and slightly pre-heat the ware, whereupon the relatively cool combustion gases are exhausted from the drying zone. The present invention also contemplates a method for fusing a porcelain enamel coating onto a piece of ware by passing the ware sequentially through the aforementioned zones, passing combustion gases in countercurrent relationship to the movement of the ware, so that most of the usable heat in the hot combustion gases is used as it passes successively through the pre-heating and drying zone and the gases can be exhausted from the drying zone at a relatively low temperature.
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