Abstract: An improved method for measuring the density and settling properties of cement slurries. The cement slurry is stirred in a consistometer and heated to a predetermined temperature. The stirring of the cement slurry is then halted and the cement slurry is cooled. The cement slurry is then removed from the consistometer.

Abstract: An improved method for measuring the density and settling properties of cement slurries. The cement slurry is stirred in a consistometer and heated to a predetermined temperature. The stirring of the cement slurry is then halted and the cement slurry is cooled. The cement slurry is then removed from the consistometer.

Abstract: Improved lost circulation compositions that include melt-processed inorganic fibers and methods for using such compositions in subterranean formations are provided. An example of a method of the present invention is a method comprising providing a drilling mud comprising a plurality of melt-processed inorganic fibers, wherein the melt-processed inorganic fibers have a length of less than about 10 millimeters, and comprise at least one melt-processed inorganic fiber selected from the group consisting of: a basalt fiber, a wollastonite fiber, and a ceramic fiber; and circulating the drilling mud in the subterranean formation.

Abstract: Provided herein are defoaming agents that comprise lecithin and a solvent. Optionally, they may comprise hydrophobic particles. One embodiment provides a method comprising: providing a well fluid that comprises foam; providing a defoaming agent that comprises lecithin and a solvent; and contacting the well fluid with the defoaming agent so that the amount of foam present in the well fluid is reduced.

Abstract: Provided herein are defoaming agents that comprise lecithin and a solvent. Optionally, they may comprise hydrophobic particles. One embodiment provides a defoaming agent that comprises lecithin and a solvent.

Abstract: Provided herein are defoaming agents that comprise lecithin and a solvent. Optionally, they may comprise hydrophobic particles. One embodiment provides a method comprising: providing a well fluid that comprises foam; providing a defoaming agent that comprises lecithin and a solvent; and contacting the well fluid with the defoaming agent so that the amount of foam present in the well fluid is reduced.

Abstract: Improved lost circulation compositions that include melt-processed inorganic fibers and methods for using such compositions in subterranean formations are provided. An example of a method of the present invention is a method of cementing in a subterranean formation. Another example of a method of the present invention is a method comprising providing a cement composition that comprises cement, water, and a plurality of melt-processed inorganic fibers, the melt-processed inorganic fibers having a mean aspect ratio of greater than about 25, a specific gravity of greater than about 1.2, and a length of less than about 10 millimeters; introducing the cement composition into a well bore that penetrates a subterranean formation; and allowing the melt-processed inorganic fibers to at least partially prevent fluid loss from the cement composition into the subterranean formation. An example of a composition of the present invention is a cement composition for use in a subterranean formation.

Abstract: Cement compositions, that comprise water, a cement, a strength-retrogression additive, and an acid, wherein the acid comprises ethylenediamine tetra acetic acid, nitrilotriacetic acid, or a combination thereof, are provided. Methods of cementing in a subterranean formation, methods of retarding the set time of a cement composition, and set retarder compositions also are provided.

Abstract: Improved apparatus and methods for determining the shear stress required for removing drilling fluid deposits formed on the walls of a well bore are provided. The methods basically comprise introducing a drilling fluid into a test apparatus which simulates a permeable section of a well bore. Drilling fluid deposits are caused to be formed on the walls of the permeable section, and the drilling fluid is circulated through the permeable section at progressively increasing flow rates for time periods whereby the pressure drop of the drilling fluid stabilizes. The stabilized pressure drop below which no appreciable erosion of the deposits takes place is determined by acoustically measuring and comparing the thicknesses of the drilling fluid deposits at each of the flow rates when the pressure drop stabilized.