Expanding additive for cement composition

摘要

Deadburned magnesium oxides (calcined at a temperature of above about 4000 DEG F.) can be advantageously utilized as an expanding additive in cements utilized to seal a metallic casing into the bore hole of a well. The deadburned magnesium oxide additives are particularly effective when used in cements having a curing temperature of about 120-200 DEG C. and particularly at temperatures greater than about 150 DEG C.