METHOD OF CEMENTING GAS OR OIL PIPELINE

摘要

The present invention relates to a method of cementing a casing of an oil or gas pipeline to a surrounding well wall, where an hydraulic cement slurr y is formed and the slurry is deployed in the annulus between the pipeline c asing and the surrounding well wall. The cement slurry is formed by mixing t ogether an hydraulic cement, 12 to 24% of silica based on the weight of ceme nt, and water; wherein the silica comprises 1/3 to 2/3 microfine silica and 2/3 to 1/3 silica flour. The invention further relates to a cement slurry fo r use in the method.