CPC Main Group F23D 1/00 Burners for combustion of pulverulent fuel 4 direct subcodes Child Classifications Navigate with arrow keys, Enter to open F23D 1/005 F23D 1/02 Vortex burners, e.g. for cyclone-type combustion apparatus F23D 1/04 Burners producing cylindrical flames without centrifugal action F23D 1/06 Burners producing sheet flames