Abstract: An apparatus for preventing or limiting the rotation of cementing plugs in a casing string during drillout. The apparatus includes an outer housing with a sleeve disposed therein. The sleeve has an inner surface configured to engage cementing plugs received therein to cause an interference fit. The sleeve will hold the cementing plugs when rotational forces, such as drilling forces, are applied so that during drillout, rotation of the cementing plug is prevented or is at least limited.

Abstract: The current invention provides a method for enhancing the formation stability of water sensitive, reactive formations penetrated by a wellbore. The method of the current invention provides an accurate evaluation of the impact of cementing fluids on water sensitive, reactive formations and provides the ability to accurately formulate cementing fluids in order to enhance the stability of such formations. When necessary, the method of the current invention additionally provides for the application of an osmotic semi-permeable membrane to the face of the formation.

Abstract: The present invention provides improved methods of cementing and cement compositions. A cement composition of the invention comprises hydraulic cement, silica hydrophobicized with a mixture of organosilicon compounds and water which upon hardening has high shear bond strength.

Abstract: The present invention provides methods of cementing pipe in well bores and low density cement compositions having enhanced compressive, tensile and bond strengths upon setting. The composition of the invention are basically comprised of a hydraulic cement, sufficient water to form a slurry and hollow glass microspheres surface treated with a mixture of organosilane coupling agents present in an amount sufficient to produce a cement composition density in the range of from about 6 to about 12 pounds per gallon.

Abstract: Methods and apparatus for preventing or limiting the rotation of downhole tools, such as cementing plugs, in a casing string during drillout. The apparatus includes an outer case and a radially expandable sleeve disposed therein. The sleeves will engage cementing plugs received therein. The sleeves radially expand when cementing plugs are received therein to grippingly engage the outer case and prevent or limit rotation thereof during drillout.

Abstract: Methods of cementing subterranean zones using cement compositions containing biogradable dispersants are provided. The methods are basically comprised of the steps of preparing a hydraulic cement, a biodegradable dispersant comprised of polyaspartic acid containing side chains formed by reacting one or more side chain chemicals with said polyaspartic acid and sufficient water to form a pumpable slurry, placing the cement composition into a zone to be cemented and allowing the cement composition to set into an impermeable solid mass therein.

Abstract: The present invention relates to foamed cement slurries, additives and methods. A foamed cement slurry of the invention comprises a hydraulic cement, sufficient water to form a slurry, sufficient gas to form a foam and an environmentally benign foaming and stabilizing additive comprising a mixture of an ammonium salt of an alkyl ether sulfate surfactant, a cocoamidopropyl hydroxysultaine surfactant, a cocoamidopropyl dimethylamine oxide surfactant, sodium chloride and water.

Abstract: In accordance with a method of this invention, formation integrity problems are discovered, diagnosed and corrected in successively drilled subterranean well bore intervals. If one or more of well bore fluid outflows, formation fluid inflows or inadequate well bore pressure containment integrity are discovered in a drilled well bore interval, well logs are run and other relevant well bore data is collected in the drilled well bore interval and analyzed to provide a specific treatment using a specific pumpable sealing composition for sealing and increasing the pressure containment integrity of the well bore. Thereafter, the sealing composition is pumped into the drilled well bore interval whereby the well bore interval is sealed or the pressure containment integrity is increased, or both.

Abstract: Methods of cementing subterranean zones penetrated by well bores using cement compositions having enhanced compressive strengths are provided. A method of the invention basically comprises the steps of preparing or providing a cement composition having enhanced compressive strength upon setting comprising a hydraulic cement, sufficient water to form a slurry and a hydroxyamine compressive strength enhancing additive. Thereafter, the cement composition is placed in a subterranean zone to be cemented and allowed to set into an impermeable solid mass therein.

Abstract: An apparatus for preventing or limiting the rotation of cementing plugs in a casing string during drillout. The apparatus includes an outer housing with a sleeve disposed therein. The sleeve has an inner surface configured to engage cementing plugs received therein to cause an interference fit. The sleeve will hold the cementing plugs when rotational forces, such as drilling forces, are applied so that during drillout, rotation of the cementing plug is prevented or is at least limited.

Abstract: Improved well cement additives, compositions and methods of using the compositions are provided. The well cement additives are basically comprised of a first monomer selected from the group of 2-acrylamido-2-methylpropane sulfonic acid, 2-allyloxy-2-hydroxy-1-propane sulfonic acid and vinylsulfonic acid, a second monomer selected from the group of N,N-dimethylacrylamide, acrylamide, N-vinylpyrrolidone, N-vinylacetamide and acrylonitrile and a third monomer selected from the group of C6 to C22 dimethylaminopropylmethacrylamide bromide, chloride and iodide and C6 to C22 dimethylaminoethylmethacrylate bromide, chloride and iodide.