Abstract: Well cementing compositions include an aqueous fluid, portland cement and an air entrainment suppressing agent. The air entrainment suppressing agent includes a blend of a silicone and polypropylene glycol, or a silicone that is functionalized with ether groups. Methods for preparing well cementing compositions comprise adding the air entrainment suppressing agent to the aqueous fluid, and combining the mixing fluid to a solid blend comprising portland cement and hydrophobic particles in a continuous process.

Abstract: A method and apparatus for making real-time measurements of downhole properties during cement plug placement. A wired placement conduit is lowered downhole releasing a sensor package. The sensor package is capable of measuring downhole properties in real-time in the period while the cement plug sets.

Abstract: An additive for Portland-cement slurries comprises an alkanolamine polyborate. When added in concert with a set retarder, the alkanolamine polyborate minimizes or prevents premature gelation during placement in a subterranean well. The additive is particularly useful for highly reactive cements, and may reduce the amount of set retarder required to achieve a given placement time.

Abstract: A cement for use in wells in which carbon dioxide is injected, stored or extracted, comprises elastomer particles. In the event of cement-matrix failure, or bonding failure between the cement/casing interface or the cement/borehole-wall interface, the elastomer particles swell when contacted by carbon dioxide. The swelling seals voids in the cement matrix, or along the bonding interfaces, thereby restoring zonal isolation.

Abstract: A method and apparatus for making real-time measurements of downhole properties during cement plug placement. A wired placement conduit (14) is lowered downhole releasing a sensor package (20). The sensor package is capable of measuring downhole properties in real-time in the period while the cement plug sets.

Abstract: A cement for use in wells in which carbon dioxide is injected, stored or extracted, comprises elastomer particles. In the event of cement-matrix failure, or bonding failure between the cement/casing interface or the cement/borehole-wall interface, the elastomer particles swell when contacted by carbon dioxide. The swelling seals voids in the cement matrix, or along the bonding interfaces, thereby restoring zonal isolation.

Abstract: The invention discloses a cement slurry composition for cementing a well comprising: an hydraulic cement, water and a combination made of a cellulosic polymer and an acrylamido-methyl-propane sulfonate co- or ter-polymer, wherein the density of said cement slurry is above 1700 kg/m3.

Abstract: A cement composition resistant to carbon dioxide includes a hollow element for trapping carbonation products. The hollow element can be hollow spherical or quasi spherical particles including cenospheres, sodium-calcium-borosilicate glass microspheres, silica-alumina microspheres, or a combination thereof. Or the hollow element may be a spherical or quasi spherical void made in the set cement, for example by foaming the cement composition with a gas such as air, nitrogen or a combination thereof. The composition may be used to cement a subterranean well in which carbon dioxide is injected, stored or produced.

Abstract: A method and apparatus for making real-time measurements of downhole properties during cement plug placement. A wired placement conduit (14) is lowered downhole releasing a sensor package (20). The sensor package is capable of measuring downhole properties in real-time in the period while the cement plug sets.

Abstract: A method and apparatus for making real-time measurements of downhole properties during cement plug placement. A wired placement conduit is lowered downhole releasing a sensor package. The sensor package is capable of measuring downhole properties in real-time in the period while the cement plug sets.

Abstract: A method and apparatus for making real-time measurements of downhole properties during cement plug placement. A wired placement conduit (30) is lowered downhole releasing a sensor package (34). The sensor package is capable of measuring downhole properties in real-time in the period while cement plug sets.

Abstract: The invention discloses a cement slurry composition for cementing a well comprising: an hydraulic cement, water and a combination made of a cellulosic polymer and an acrylamido-methyl-propane sulfonate co- or ter-polymer, wherein the density of said cement slurry is above 1700 kg/m3.

Abstract: The invention provides a cement composition resistant to carbon dioxide including a hollow element for trapping carbonation products. The hollow element can be an additional component added to the cement composition, this component is made of hollow spherical or quasi spherical particles as cenospheres, sodium-calcium-borosilicate glass, silica-alumina microspheres, or a combination thereof. Or the hollow element is a spherical or quasi spherical void made in the set cement, for example by foaming the cement composition with a gas as air, nitrogen or a combination thereof. Use of such cement composition in carbon dioxide application is disclosed. Additionally, a method to cement a part of a borehole in presence with carbon dioxide is disclosed, a method to repair a part of a borehole in presence with carbon dioxide is disclosed using the above cement composition and a method to plug a part of a borehole in presence with carbon dioxide is disclosed.

Abstract: A wiper plug launching tool includes a body arranged to be lowered into a liner on a running string, the body having a tubular upper portion and a cylindrical lower portion, upper and lower wiper plugs loaded into the lower portion, each of the plugs having upwardly facing elastomer cups that are reduced in diameter during loading, a drive rod movably mounted in the upper portion of the body, a first piston or dart that is pumped down the running string and into engagement with the drive rod so that pressure applied to the first dart forces the rod downward to cause ejection of the lower wiper plug into the liner where cups of the plug expand to provide a moving seal at the lower end of a column of cement, and a second piston or dart that is pumped down into engagement with the first dart to force the rod further downward and cause ejection of the upper wiper plug into the liner where the cups of this plug expand to provide a moving seal at the upper end of the column of cement.

Abstract: The invention consists of a new process for selectively treating a subterranean formation without affecting or being effected by the two adjacent zones (above and below).Using the invented process, the treatment fluid is injected into the formation to be treated F, at the same time as two protection fluids, whether the same or different, are injected into the two adjacent zones (above [ZS] and below [ZI]).The process can be applied even in the presence of fractures, gravel-pack and their zones.