Abstract: A radiation heating apparatus comprising a heating zone, a zone to be heated, a gas non-permeable boundary member defining the boundary between the two zones, and a porous radiator member provided in the heating zone, wherein a high-temperature gas is formed in, or introduced into, the heating zone and discharged at least through the porous radiator member, and the zone to be heated is heated through the gas non-permeable boundary member.

Abstract: A radiant tube to be heated by high-temperature gases supplied from its one end. The tube supplys a heat radiation by being thus heated. The gases used for the heating are discharged from the other end of the tube. Inside the tube a heat exchanger is provided in the proximity of the gas outlet of the tube so as to recover thermal energy from the used gases before they come out from the outlet.

Abstract: Method and apparatus for heating materials such as metal rods whereby hot combustion gases are blown against the material and allowed to pass through a gas-permeable partition located inside the heating apparatus so that the partition is heated to radiate a great amount of heat into the apparatus, further increasing the temperature of atmosphere in the apparatus heated by the hot combustion gases so as to accelerate the heating of the material. After the combustion gases have thus passed through the partition, heat is further transferred from the gases to a recuperator means located inside the apparatus so that the gases are then allowed to discharge into a flue under lowered temperatures.