BigPatents India

This invention is about the process and equipment used for developing a protective carbon coating by partial burning of hydrocarbon gases on the internal surfaces of metallic trays that carry metallic powders (like iron powder) for thermal treatment (reduction, annealing etc.) in pusher and walking beam furnaces which prevents powder from sticking to trays. The inflammable hydrocarbon gas passes through thin slits provided on 'height-adjustable' metallic burners, screwed on to equidistant branched metallic pipes connected to a metallic main pipe having a regulator. The partial burning of regulated hydrocarbon gas and oxygen flow create laminar flame ensuring uniform deposition of protective carbon layer on internal surface of trays placed one at a time on the array of burners. After coating the tray is removed. This carbon layer gasifies during thermal treatment and does not contaminate the powder while facilitating its smooth unloading from the trays.