Basic refractory cementitious material and components thereof

A cast refractory shape produced from an hydraulic refractory cementitious formulation consisting essentially of:

• 70 to 86% of a magnesia component containing at least 94% MgO,
• 5to 15% of an alumina component containing at least 98% Al.sub.2 O.sub.3,
• 9 to 15 % of an aluminous cement component containing at least 45% Al.sub.2 O.sub.3,
• said formulation after wetting being capable of hydraulically setting at room temperature,
• said cast refractory shape having a cold crushing strength after subjection to temperatures of 110.degree., 1000.degree. and 1500.degree. C. of about 492, 517 and 868 kp/cm.sup.2 respectively and a bulk density after subjection to these temperatures of about 2.83, 2.78 and 2.85 g/cc.

A method of making a refractory part, comprising:

• preparing a hydraulic refractory cementitious formulation consisting essentially of
• 70 to 86% of a magnesia component containing at least 94% MgO,
• 5 to 15% of an alumina component containing at least 98% Al.sub.2 O.sub.3,
• 9 to 15% of an aluminous cement component containing at least 45% Al.sub.2 O.sub.3,
• said formulation after wetting being capable of hydraulically setting at room temperature,
• adding water to the formulation so as to obtain a hydraulic concrete,
• forming the part in a mold by vibration casting said hydraulic concrete therein,
• and curing the casting and allowing it to dry.