Abstract: A tank construction including an outer shell of steel material comprised of two half members welded together. The half members are formed by a deep drawing process. An inner shell of non-corrosive material is cast inside the outer shell by a rotational casting procedure with the external surface of the inner shell located adjacent the internal surface of the outer shell. The inner shell of non-corrosive material provides a substantially leak-fight liner for the outer shell to thus prevent contact between the contents of the tank and the outer shell. The rotational casting of the inner shell inside the outer shell is accomplished by charging the outer shell with a non-corrosive material and then subjecting the outer shell to a rotational casting movement while heat is applied to the outer shell. The outer shell serves as a mold for the inner shell wherein the mold (outer shell) becomes a permanent part of the completed tank.

Abstract: A tank construction including an outer shell of steel material comprised of two half members welded together. The half members are formed by a deep drawing process. An inner shell of non-corrosive material is cast inside the outer shell by a rotational casting procedure with the external surface of the inner shell located adjacent the internal surface of the outer shell. The inner shell of non-corrosive material provides a substantially leak-tight liner for the outer shell to thus prevent contact between the contents of the tank and the outer shell. The rotational casting of the inner shell inside the outer shell is accomplished by charging the outer shell with a non-corrosive material and then subjecting the outer shell to a rotational casting movement while heat is applied to the outer shell. The outer shell serves as a mold for the inner shell wherein the mold (outer shell) becomes a permanent part of the completed tank.

Abstract: A water heater including a watertight tank having a source of heat for heating water inside the tank and a hot water outlet mounted in the top portion of the tank. An agitator assembly is mounted in the bottom portion of the tank and includes a ring-shaped tubular member and a secondary tubular member connected to the ring-shaped tube. The ring-shaped member is provided with a plurality of openings in the sides thereof and said secondary tubular member is provided with an upwardly facing opening therein. A plurality of horizontally extending venturi fittings are mounted in the ring-shaped member side openings and an upwardly extending venturi fitting is mounted in the secondary tubular member opening. The agitator assembly is connected to a source of water so that when hot water is periodically withdrawn from the top of the tank water will flow into the tank through the openings and venturi fittings in the agitator assembly.

Abstract: A water heater including a watertight tank having a plurality of flue tubes extending between the tank bottom and the tank top and having a burner means mounted beneath the tank and a hot water outlet mounted in the top portion of the tank. An agitator assembly is mounted in the bottom portion of the tank and includes a ring-shaped tubular member and a secondary tubular member connected to the ring-shaped tube. The ring-shaped and secondary tubular members are provided with a plurality of openings in the sides thereof. The agitator assembly is connected to a source of water so that when hot water is periodically withdrawn from the top of the tank water will flow into the tank through the openings in the agitator assembly. Such openings are positioned so that water flowing from inside the tubular members into the tank will flow in a number of different horizontal directions to thereby produce a substantially uniform stirring action in the bottom portion of the tank.