초록 ▼

A 9 to 12 ppg (1.08 to 1.4 kg/liter) cement slurry for use in oil well type completions which comprises hydraulic cement about 10 to about 30 weight percent hollow glass microspheres based on the weight of the cement and sufficient water to form a pumpable slurry with an API free water content of no

A 9 to 12 ppg (1.08 to 1.4 kg/liter) cement slurry for use in oil well type completions which comprises hydraulic cement about 10 to about 30 weight percent hollow glass microspheres based on the weight of the cement and sufficient water to form a pumpable slurry with an API free water content of no more than about 2 volume percent. This slurry is preferably mixed with an amount of water required to produce a slurry with the hydraulic cement having at least an API minimum water content and an API free water content of no more than about 2 volume percent and an additional amount of water equal to about 1.3 to about 1.8 weight percent water based on the weight of the hydraulic cement for each weight percent of the microspheres. The microspheres have true particle densities of about 0.2 to about 0.5 gm/cm3, hydrostatic collapse strengths of at least 500 psi (3447 kPa) and average particle diameters of less than about 500 microns.

대표청구항 ▼

A hydraulic cement slurry which comprises as its essential components: hydraulic cement, about 8 to about 50 weight percent hollow glass microspheres by weight of the cement and sufficient water to form a pumpable slurry, wherein the API free water content of said slurry is no more than about 2 volu

A hydraulic cement slurry which comprises as its essential components: hydraulic cement, about 8 to about 50 weight percent hollow glass microspheres by weight of the cement and sufficient water to form a pumpable slurry, wherein the API free water content of said slurry is no more than about 2 volume percent based only on said hydraulic cement and said microspheres, and said microspheres have ANSI/ASTM D 2840-69 average true particle densities of about 0.2 to about 0.5 gm/cm3, ANSI/ASTM D 3102-72 hydrostatic collapse strengths of at least 500 psi (3447 kPa) and average particle diameters of less than about 500 microns.