Abstract: A device for extinguishing fires in a flammable liquid storage tank uses either foam or dry chemical powder, or both, as the extinguishant. The device comprises at least one annular pipe ring arranged in a horizontal plane just above the bottom of the storage tank and connected to a supply of extinguishant. When more than one ring is used, the rings are concentrically and equidistantly arranged with the outermost ring connected to the supply of extinguishant. The pipe rings have two or more diametrically connected cross-members. Vertically extending discharge pipes are situated at the junctions of the pipe rings and cross-members. The top ends of the discharge pipes are above the highest level of flammable liquid in the storage tank and are equipped with discharge nozzles. The discharge nozzles provide for uniform discharge of the extinguishant onto the surface of the flammable liquid held in the storage tank.

Abstract: A fixed roof flammable liquid storage tank with a fire extinguishing device is disclosed. The tank has a hydraulically leakproof base, a conical slope ranging from 30.degree. to 60.degree. relative to the base, and a conical circular wall made of a plurality of metal plates joined together to form an upwardly tapered conical wall. The conical wall reaches up to a height where the top diameter reduces in the range of one-third to two-thirds of the base diameter of the tank to form a frustum. The tank is provided with a fire extinguishing device comprising one or more annular pipe rings connected by cross-member pipes with vertical discharge pipes attached at the junctions therebetween. The pipes extend above the highest level of the liquid in the tank and are configured to distribute either foam or dry chemical powder to extinguish a fire.