دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a siliceous volcanic rock that is finely ground and subjected to extreme heat. The resulting release of water leaves the rock particles considerably expanded and thus more porous. Expanded perlite is sometimes used in cement to increase its yield and decrease its density without an appreciable effect on its other properties.

n: a siliceous ash rock which is grinded and processed under the hyperthermic situation,usually used to improve the mud making rate of the cement slurry and decline the density