Abstract: An apparatus for measuring the permeability and diffusivity of a porous solid includes a device for measuring permeability of the solid; a device for measuring diffusivity of the solid; a sample chamber for holding a sample of the solid, the arrangement being such that the permeability and diffusivity can be measured without removing the sample from the sample chamber.

Abstract: Apparatus for measuring the permeability and diffusivity of a porous solid comprising: a permeability measuring means for measuring permeability of the solid; a diffusivity measuring means for measuring diffusivity of the solid; a sample chamber for holding a sample of the solid, the arrangement being such that the permeability and diffusivity can be measured without removing the sample from the sample chamber.

Abstract: An apparatus for testing a rheological property of a fluid with a particulate includes: (a) a receptacle having a cylindrical side wall enclosed by a bottom wall defining a cavity for receiving a fluid to be tested; (b) an axial support adapted to be positioned in the cavity of the receptacle, whereby relative rotational motion can be imparted to the receptacle and the axial support; (c) at least one inward projection extending inward from an inside surface of the receptacle; (d) at least one outward projection extending outward from the axial support; and (e) at least one projection for directing fluid flow that has at least one major surface angled or curved upward. A method of testing a rheological property of a fluid with a particulate includes: (a) placing a sample of the fluid and the particulate in the apparatus; (b) imparting relative rotational motion to the receptacle and the axial support; and (c) measuring the torque between the receptacle and the axial support.

Abstract: An apparatus for testing a rheological property of a fluid with a particulate includes: (a) a receptacle having a cylindrical side wall enclosed by a bottom wall defining a cavity for receiving a fluid to be tested; (b) an axial support adapted to be positioned in the cavity of the receptacle, whereby relative rotational motion can be imparted to the receptacle and the axial support; (c) at least one inward projection extending inward from an inside surface of the receptacle; (d) at least one outward projection extending outward from the axial support; and (e) at least one projection for directing fluid flow that has at least one major surface angled or curved upward. A method of testing a rheological property of a fluid with a particulate includes: (a) placing a sample of the fluid and the particulate in the apparatus; (b) imparting relative rotational motion to the receptacle and the axial support; and (c) measuring the torque between the receptacle and the axial support.

Abstract: An apparatus for testing a rheological property of a fluid with a particulate includes: (a) a receptacle having a cylindrical side wall enclosed by a bottom wall defining a cavity for receiving a fluid to be tested; (b) an axial support adapted to be positioned in the cavity of the receptacle, whereby relative rotational motion can be imparted to the receptacle and the axial support; (c) at least one inward projection extending inward from an inside surface of the receptacle; (d) at least one outward projection extending outward from the axial support; and (e) at least one projection for directing fluid flow that has at least one major surface angled or curved upward. A method of testing a rheological property of a fluid with a particulate includes: (a) placing a sample of the fluid and the particulate in the apparatus; (b) imparting relative rotational motion to the receptacle and the axial support; and (c) measuring the torque between the receptacle and the axial support.

Abstract: A test cell for testing a sample cement composition includes a test chamber and a variable stress system. The test chamber is configured to hold a sample cement composition for a wellbore. The variable stress system communicates with the test chamber. Performance of the sample cement composition is tested for a wellbore using the variable stress system.

Abstract: A conventional Couette viscometer is transformed to measure yield point, also known as yield stress, and other rheology of various fluids, including ones with particulates. A rotating viscometer includes a driven portion, a responsive body, a standard spring, and a plurality of fins. The fins have predetermined shapes such that the rotating viscometer and the standard spring, connected to the responsive body having at least a portion of the fins, are sensitive to detect yield stress of a test fluid composition in response to a selected rotation imparted to the driven portion. A method of measuring yield stress includes operating a standard rotating viscometer modified with a plurality of intermeshing fins such that a standard spring of the standard rotating viscometer responds to a torque that is related to yield stress and that is imposed by a stressed test material on a portion of the fins connected to the spring.

Abstract: The present invention relates to a gel hydration tank and method for hydrating gels for use in oil well treatment operations according to which a mixture of water and gel is introduced into the interior of the tank and flows through the tank before being discharged from the tank, whereby specific devices are used to deflect and/or re-direct fluid flow so as to increase the distance traveled for a given fluid volume element, which consequently increases the plug flow efficiency of the tank.

Abstract: A device and a method for testing a viscosified fluid containing particulate indicate when the particulate is in suspension within the fluid and when it is not. The device and method stir the fluid and particulate mixture for a time during which the viscosity of the fluid changes such that during a first period of the stirring time substantially all the particulate remains suspended in the fluid and during a second period of the stirring time substantially all the particulate settles out of suspension in the fluid. A signal is generated during the first and second periods such that the signal has a characteristic that changes from the first period to the second period to indicate the change in particle carrying ability of the fluid. Other characteristics, including crosslinking time, can also be determined. A test chamber includes interacting projections extending from the inner surface of a cup receiving the fluid and from an axial support extending into the fluid in the cup.

Abstract: A conventional Couette viscometer is transformed to measure yield point, also known as yield stress, and other rheology of various fluids, including ones with particulates. A rotating viscometer includes a driven portion, a responsive body, a standard spring, and a plurality of fins. The fins have predetermined shapes such that the rotating viscometer and the standard spring, connected to the responsive body having at least a portion of the fins, are sensitive to detect yield stress of a test fluid composition in response to a selected rotation imparted to the driven portion. A method of measuring yield stress includes operating a standard rotating viscometer modified with a plurality of intermeshing fins such that a standard spring of the standard rotating viscometer responds to a torque that is related to yield stress and that is imposed by a stressed test material on a portion of the fins connected to the spring.

Abstract: The present invention relates to a gel hydration tank and method for hydrating gels for use in oil well treatment operations according to which a mixture of water and gel is introduced into the interior of the tank and flows through the tank before being discharged from the tank, whereby specific devices are used to deflect and/or re-direct fluid flow so as to increase the distance traveled for a given fluid volume element, which consequently increases the plug flow efficiency of the tank.

Abstract: A device and a method for testing a viscosified fluid containing particulate indicate when the particulate is in suspension within the fluid and when it is not. The device and method stir the fluid and particulate mixture for a time during which the viscosity of the fluid changes such that during a first period of the stirring time substantially all the particulate remains suspended in the fluid and during a second period of the stirring time substantially all the particulate settles out of suspension in the fluid. A signal is generated during the first and second periods such that the signal has a characteristic that changes from the first period to the second period to indicate the change in particle carrying ability of the fluid. Other characteristics, including crosslinking time, can also be determined. A test chamber includes interacting projections extending from the inner surface of a cup receiving the fluid and from an axial support extending into the fluid in the cup.

Abstract: The present invention provides methods and apparatus for simulating well bore conditions before and after cementing therein. The methods of the invention are basically comprised of the steps of circulating a drilling fluid through a closed test cell containing a permeable rock core while maintaining a selected pressure differential across the rock core to form a layer of filter cake thereon, circulating a filter cake removal fluid through the test cell to simulate the clean-up of the well bore and then determining the condition of the rock core with respect to the effectiveness of the filter cake removal fluid thereon.

Abstract: A positive stirring consistometer cup includes a pair of wall blade members having radially inwardly extending blades which cooperate with radially outwardly extending blades of a paddle to uniformly apply shear throughout a substance to be tested. A split sleeve assembly eliminates an outer dead space, and an enlarged spacer member mounted on the shaft of the paddle eliminates an inner dead space, thereby enhancing the uniformity of the shear throughout the substance. A centralizing assembly centers the stationary paddle while causing a minimum of friction and wear to occur on the shaft of the paddle. In a method of using the positive stirring consistometer cup, the blades of the wall blade members and of the paddle stop in substantially aligned, coplanar relationship to facilitate cleaning of the elements after a test is concluded.