CPC Main Group C23D 9/00 Ovens specially adapted for firing enamels 5 direct subcodes Child Classifications Navigate with arrow keys, Enter to open C23D 9/02 Non-electric muffle furnaces C23D 9/04 Non-electric tunnel ovens C23D 9/06 Electric furnaces C23D 9/08 Supporting devices for burning-bars C23D 9/10 Loading or unloading devices