High speed tunnel kiln for baking porcelain - with indirect cooling of the slides carrying the porcelain through the kiln

摘要

Tunnel kiln for the high speed baking of workpieces, esp. porcelain, where the workpieces travel through the kin on slides. At least the high temp. zone of the kiln is fitted with a device for the indirect cooling of the longitudinal sides and/or the underside of the slides. The cooling device pref. employs tubes with a rectangular cross-section, where the tubes are laid parallel with the direction of slide travel so =1 outer wall of the tubes is near the longitudinal sides of the slides; and each tube has an inlet and outlet for air obtd. from the atmos. surrounding the furnace. High speed tunnel kilns are ued for sintering ferrites, and the short cycle time would be very useful for porcelain prods., bu the slides have not been able to withstand the baking temp. of 1400 degrees C. The invention provides local cooling of the slides so porcelain can be baked in high speed kilns.