Passive heat-resistant malleable cast iron fire grate segment

The utility model discloses a malleable cast iron passive heat-resisting fire grate segment which comprises a fire grate segment transverse plate and a fire grate segment vertical plate, the fire grate segment vertical plate is arranged in the middle of the bottom end of the fire grate segment transverse plate, air grooves are formed in the two walls of the fire grate segment transverse plate, and through holes are formed in the surface of the fire grate segment vertical plate. The first lantern ring is arranged on the side, close to the through hole, of the grate segment vertical plate, a second lantern ring is arranged on the other side, close to the through hole, of the grate segment vertical plate, a limiting groove is formed in the outer wall of the first lantern ring, and a limiting block is arranged on the outer wall of the second lantern ring. According to the malleable cast iron passive heat-resisting fire grate segment, the limiting block of one fire grate segment is in butt joint with the limiting