Abstract: A sealing device for a rotating furnace and cooler for calcination of oil coke has lead plates mounted in sliding form on individual supports attached to a flange which constitutes the fixed part of the furnace or cooler. The plates are aligned side by side, forming a collar of coplanar plates encircling the external diameter of the furnace or cooler, forming a self-adjustable sealing curtain between the joint point of its rotating and fixed parts, while the cylindrical body presents a track against which all plates are handled and held with a certain pressure, maintaining the sealing between the rotating and fixed part of the set, both in the furnace and in the cooler.