Low-density cementing slurry

摘要

A well cementing slurry, includes a solid fraction and a liquid fraction and has a density of less than about 1500 kg/m<3>. The solid fraction includes a mixture of solid particulate materials including cement, having 60% to 90% by volume of the solid fraction of a first component with particles having a mean size lying in the range 20 microns to 400 microns and a density of less than 2000 kg/m<3>; and 10% to 30% by volume of the solid fraction of a second component having a mean particle diameter of less than 5 microns.