To make a breaking load in the orthogonal direction to the lateral side larger than the one of an ordinary checker brick of a hot-blast stove by a method wherein the ratio in a bore between the central hole and adjacent holes of a hexagonal- pillar-shaped body so stacked that a large number of gas passages communicate with each other is set to be in a specific range.
A checker brick 22 has a brick main body 23 formed in the shape of a hexagonal pillar. A gas passage hole A11 is formed in the center of this brick main body 23 and six gas passages B11-B16 on the concentric circle and at prescribed angles from the center so that they pierce the main body vertically, and thereby the gas passages totaling seven are prepared. Besides, gas passages each having the shape of a 1/3 circle of the hole A11 are formed at the apexes of the hexagon of the main body 23 and ones each having the shape of a 1/2 circle of the hole B11 at the centers of the sides of the hexagon respectively so that they pierce the main body vertically, and thereby the gas passages totaling twelve are prepared. The ratio in a bore between the gas passage hole A11 and the gas passage holes B11-B16 is set to be in a range of 1.4 to 2.1. According to this constitution, a breaking load in the orthogonal direction to the lateral side can be made larger than the one of an ordinary checker brick of a hot-blast stove.
ISHII AKIO
KASAI KATSUTERU
