Abstract: The current method comprises producing a loss control blend by selecting blend ingredients that contribute to thixotropy of the blend, density of the blend, and compressive strength of the set blend, wherein at least one of the blend ingredients contributes positively to all three of these attributes.

Abstract: Methods of forming an aqueous silica suspension are provided. The methods include admixing water, an organic acid, a silica powder, and a siliconate under certain conditions. The silica powder includes undensified silica powder in an amount of at least about 50% by weight and has a specific gravity in the range of from about 2.1 to about 2.5, a bulk density in the range of from about 12 lb/ft3 to about 40 lb/ft3, and a water requirement of from about 80 to about 250 at a pH in the range of from about 5.5 to about 7.5. Also provided are aqueous silica suspensions, hydraulic cement compositions, and methods of cementing in a well.

Abstract: Methods and apparatuses for determining surface wetting of metallic materials at downhole wellbore condition with fixed or changing well fluids are disclosed. In general, the methods according to the disclosure include carrying out an electrical impedance spectroscopy (“EIS”) for a system simulating downhole conditions for the wetting of a surface by simultaneously dynamically moving electrodes exposed to the well fluid while measuring the changes in electrical characteristics between the electrodes.

Abstract: A method of performing a static gel strength test on a composition can include placing the composition into a static gel strength test instrument, stirring the composition with at least one helical blade of the instrument, and measuring resistance to rotation between a stator and a rotor of the instrument. A static gel strength test instrument can include a rotor, and a stator having at least one helical blade. The static gel strength test instrument characterizes gelation of a composition. Another static gel strength test instrument can include a stator having at least one helical blade, and a rotor having at least one helical blade.

Abstract: A method of determining rheological properties can include dispensing a fluid into a rheometer including a stator having at least one helical blade, measuring torque (T) due to relative rotation between the stator and a rotor of the rheometer at different rotational speeds (RPM's), calculating shear stress (SS) as follows: SS=T?/K, and calculating volume averaged shear rate (VASR) as follows: VASR=k1*RPM?, where K, k1, ? and ? are experimentally-derived coefficients. A method of mixing fluids and performing a rheological test on the admixed fluids can include dispensing a fluid into a rheometer, then dispensing another fluid into the rheometer, then mixing the fluids with at least one helical blade of the rheometer, and then measuring torque due to relative rotation between a stator and a rotor of the rheometer. A rotary rheometer can include a rotor, and a stator having at least one helical blade.

Abstract: Methods and apparatuses for determining surface wetting of a metallic material with changing well fluids. In general, the methods according to the invention include measuring electrical impedance spectroscopy (“EIS”) for a system simulating downhole conditions for the wetting of a surface. Methods and apparatuses for making EIS measurements model double-layer capacitance at a downhole surface in a well, from which the nature and quantification of the wetting of the surface can be inferred.

Abstract: Disclosed is an apparatus and method for testing a cemented bonding with the formation under wellbore pressure conditions. The apparatus comprises a pressure chamber containing a core of formation material. The cement material to be tested is allowed to set or bond to one side of the core while formation fluids under wellbore pressure conditions are present on the other side. Leakage of formation fluids is measured to evaluate the quality of the interface between the cement and formation materials.

Abstract: A method of determining rheological properties can include dispensing a fluid into a rheometer including a stator having at least one helical blade, measuring torque (T) due to relative rotation between the stator and a rotor of the rheometer at different rotational speeds (RPM's), calculating shear stress (SS) as follows: SS=T?/K, and calculating volume averaged shear rate (VASR) as follows: VASR=k1*RPM?, where K, k1, ? and ? are experimentally-derived coefficients. A method of mixing fluids and performing a rheological test on the admixed fluids can include dispensing a fluid into a rheometer, then dispensing another fluid into the rheometer, then mixing the fluids with at least one helical blade of the rheometer, and then measuring torque due to relative rotation between a stator and a rotor of the rheometer. A rotary rheometer can include a rotor, and a stator having at least one helical blade.

Abstract: Methods and apparatuses for determining surface wetting of a rock material with changing well fluids. In general, the methods according to the invention include measuring electrical impedance spectroscopy (“EIS”) for a system simulating downhole conditions for the wetting of a surface. Methods and apparatuses for making EIS measurements model double-layer capacitance at a downhole surface in a well, from which the nature and quantification of the wetting of the surface can be inferred.

Abstract: An embodiment includes a method of servicing a well bore. The method may comprise introducing a lost circulation composition into a lost circulation zone, the lost circulation composition comprising hydraulic cement, nano-particles, amorphous silica, clay, and water. The method further may comprise allowing the lost circulation composition to set in the lost circulation zone. Another embodiment includes a lost circulation composition. The lost circulation may comprise hydraulic cement, nano-particles, amorphous silica, clay, and water.

Abstract: A method of performing a static gel strength test on a composition can include placing the composition into a static gel strength test instrument, stirring the composition with at least one helical blade of the instrument, and measuring resistance to rotation between a stator and a rotor of the instrument. A static gel strength test instrument can include a rotor, and a stator having at least one helical blade. The static gel strength test instrument characterizes gelation of a composition. Another static gel strength test instrument can include a stator having at least one helical blade, and a rotor having at least one helical blade.

Abstract: Disclosed is a fluid testing device which utilizes a small, cross-section fluid interface to separate a test fluid chamber from a drive and measuring chamber. The test fluid chamber contains the test fluid and a paddle-type fluid test assembly. The drive and measuring chamber contains a second fluid and assemblies for moving the paddle and for determining the resistance movement. The two chambers are connected together by a narrow cross-section passageway allowing for continuous testing while test fluids are flowed through the test chamber and for successive testing of different samples without breaking down the device between tests. A pair of coaxial shafts extends between the test fluid chamber and the drive and measuring chamber. The shafts are connected together by a spring located in the drive chamber whereby the resistance to movement is determined by measuring the deflection in the spring. The shafts are magnetically coupled to a motor to rotate the shafts.

Abstract: Disclosed is a fluid testing device which utilizes a small, cross-section fluid interface to separate a test fluid chamber from a drive and measuring chamber. The test fluid chamber contains the test fluid and a paddle-type fluid test assembly. The drive and measuring chamber contains a second fluid and assemblies for moving the paddle and for determining the resistance movement. The two chambers are connected together by a narrow cross-section passageway allowing for continuous testing while test fluids are flowed through the test chamber and for successive testing of different samples without breaking down the device between tests. A pair of coaxial shafts extends between the test fluid chamber and the drive and measuring chamber. The shafts are connected together by a spring located in the drive chamber whereby the resistance to movement is determined by measuring the deflection in the spring. The shafts are magnetically coupled to a motor to rotate the shafts.