Casting material and structure of water cooled steel brick for blast furnace

The structure of the water-cooled steel brick casting is complex (see Figure), and the water pressure test of 0.5MPa is required, and there is no “sweating” phenomenon after holding for 1H. The overall dimension of water-cooled steel brick is 1022.7mm × 600mm × 868mm, the interior is a closed cavity, and the exterior is inlaid with two pieces with a total height of 400mm φ 40mm × 6 mm A3 seamless steel pipe, steel pipe lining pipe.

Seamless steel pipe and protecting pipe are easy to deform under the action of high temperature liquid steel, so the dimensional accuracy of casting is difficult to control. There are two fixing bolt holes (casting holes) with a height of 860mm inside the casting and running through the whole casting, which are the installation and positioning holes of steel brick. Therefore, the position accuracy and dimension accuracy of the holes are strictly required, otherwise the fixing and assembly of furnace wall will be affected. The maximum thickness of the casting is 150 mm and the minimum thickness is 30 mm.

For steel castings, the wall thickness is very uneven, and the tendency of forming shrinkage cavity, shrinkage porosity, cracks and other casting defects is large. 70% of the casting surface is not machined, and two forging claw rings need to be cast into the arc surface without cooling water pipe, so as to facilitate the hoisting during the installation of blast furnace.