Industrial furnace, especially a multi-chamber ring furnace

1. The industrial furnace, especially a multi-chamber ring furnace, contains gas burners located in air-and-exhaust ducts, while the furnace chamber is divided into cases. The chamber is made of interlaced layers of fire-proof cuboidal shapes with rectangular bases, equipped with projections and corresponding recesses in the opposite walls. The shapes have one, two or no openings. The openings establish vertical exhaust ducts in the furnace cross-section. Characterized in that: The corners of the chamber (1) and the nodes of the cases (2) are made of at least two fire-proof, cuboidal shapes (4). Their bases are differentiated and non-rectangular in shape. They are equipped with projections corresponding to recesses in the opposite walls. They are laid in layers consisting of at least two repeated sets. They create expansion gaps (6) in the brickwork.