... 4. Quality is good. 5. The lowest price Fire bricks SK Series Characteristics: 1. High refractoriness. 2. Good spalling resistance and ... (≥)3035384555657082Fe2O3 % (≤)2.52.52.02.02.02.02.02.0Refractoriness(SK)3032343536373840Refractoriness under load, 0.2MPa, °C (≥)12501300135014001450148015501600Apparent porosity (%)22-2622 ... .5-2.7Cold crushing strength ,MPa (≥)2020253040455070 Fire bricks SK Series