| 摘要 |
PROBLEM TO BE SOLVED: To impart a close structure and high strength at high temp. and an excellent erosion resistance to slag without lowering heat spalling resistance by forming a blended material containing a resin-coated magnesia grain and carbon. SOLUTION: A steel tapping hole sleeve refractory is formed with the blended material containing the resin-coated magnesia grains composed of electromelting clinker, burnt clinker, natural magnesite or the like and, on the magnesia grains, applied with a novolak-resol type phenol resin, and the carbon of natural flake- graphite, artificial graphite or the like. Grain sizes of the magnesia grains are made to 1-5 mm, and the fixed carbon content in the coated-resin is made to >=20 wt.%, and it is desirable to use 0.5-2 pts.wt. of the resin per 100 pts.wt. of the magnesia grains. Further, if necessary, as the other components, Al, Si, Al-Mg, B4C, or the like, can be added. |
