... insulating firebrick (Grade 23)is made from high-grade and high purity refractory powders and materials. During the process of production, organic ... various furnaces in the industry of metallurgy,petrochemical,ceramics,machinery and building materials.For instance:the cracking furnace,conversion furnace, ... information,please contact us ! Insulating Firebrick ( LYMZ-23A,best quality and lowest price )