Low-density and low-porosity cementing slurry for oil wells or the like

摘要

The invention relates to a cement slurry for cementing an oil well or the like, the slurry having a density lying in the range 0.9 g/cm<3 >to 1.3 g/cm<3>, and being constituted by a solid fraction and a liquid fraction, having porosity lying in the range 38% to 50%. The solid fraction is constitued by a mixture of lightweight particles, microcement and optionally portland cement and gypsum. Such cements have remarkable mechanical properties due to their very low porosity in spite of having very low density.