Abstract: Methods for designing lost circulation materials for use in drilling wellbores penetrating subterranean formations may involve inputting a plurality of first inputs into a numerical method, the plurality of first inputs comprising a lost circulation material property input of a first LCM; calculating a plurality of first outputs from the numerical method; inputting a plurality of second inputs into the numerical method, the plurality of second inputs comprising the lost circulation material property input of a second lost circulation material; calculating a plurality of second outputs from the numerical method; comparing the first outputs to the second outputs; and developing a drilling fluid comprising a third lost circulation material based on the comparison of outputs.

Abstract: Equipment associated with a gelled fluid may be manipulated based on a stress response of the gelled fluid as determined by a gel microstructure destruction model comprising an equivalent work integral function. Further, systems and devices may be configured to manipulated equipment associated with a gelled fluid based on a stress response of the gelled fluid as determined by a gel microstructure destruction model comprising an equivalent work integral function.

Abstract: Invert emulsion drilling fluids that have extended emulsion stability and reduced sag potential are described herein. The drilling fluids comprise an invert emulsion, a weighting agent, and a plurality of colloidal particles. The invert emulsion comprises an oleaginous fluid continuous phase, an aqueous fluid internal phase, and a surfactant. At least a portion of the plurality of colloidal particles interact with the surfactant to form an associative supporting structure that inhibits sag of the weighting agent. In some embodiments, the weighting agent comprises barite particles, particularly barite particles that are less than about 45 ?m in size. Methods for placing the invert emulsion drilling fluids in a subterranean formation via a wellbore are also disclosed.

Abstract: Variable pressure weighting material particles that include a hollow, elastically deformable particle which itself comprises a wall and an internal fluid at a pressure of 15 psi to about 100 psi. The variable pressure weighting material particles generally include a hollow, elastically deformable particle that compresses during introduction into a subterranean formation and returns to substantially the same shape when removed from the subterranean formation.

Abstract: Invert emulsion drilling fluids that have extended emulsion stability and reduced sag potential are described herein. The drilling fluids comprise an invert emulsion, a weighting agent, and a plurality of colloidal particles. The invert emulsion comprises an oleaginous fluid continuous phase, an aqueous fluid internal phase, and a surfactant. At least a portion of the plurality of colloidal particles interact with the surfactant to form an associative supporting structure that inhibits sag of the weighting agent. In some embodiments, the weighting agent comprises barite particles, particularly barite particles that are less than about 45 ?m in size. Methods for placing the invert emulsion drilling fluids in a subterranean formation via a wellbore are also disclosed.

Abstract: Methods and systems for characterizing drilling fluids laden with LCM (Lost Circulation Material) and other solid materials are disclosed. A test cell for analyzing a fluid is provided with a first conical inner portion and an axial positioning device positioned along an axis of the test cell. A first conical plug is coupled to the axial positioning device and is movable in and out of the first conical inner portion along the axis of the test cell. A fluid inlet is positioned at a first location on the test cell and a fluid outlet at a second location.

Abstract: The present invention provides variable density fluid compositions and methods for using such compositions in a subterranean formation. One exemplary embodiment of the variable density fluid compositions of the present invention comprises a variable density fluid comprising: a base fluid, and a portion of variable pressure weighting material particles.

Abstract: Designed drilling fluids and methods of designing and using designed drilling fluids are disclosed. In one embodiment, a method of designing a drilling fluid comprises the step of determining a Design Space comprising specified ranges for one or more drilling fluid properties. The method further comprises determining a Final Fluid Formulations Set comprising drilling fluid compositions having drilling fluid properties compatible with the Design Space and satisfying one or more Performance Criterion. The method further comprises selecting a subset of drilling fluid compositions from the Final Fluid Formulations Set. The method further comprises preparing a drilling fluid based on the subset of drilling fluid compositions.

Abstract: Methods and systems for characterizing drilling fluids laden with LCM (Lost Circulation Material) and other solid materials are disclosed. A test cell for analyzing a fluid is provided with a first conical inner portion and an axial positioning device positioned along an axis of the test cell. A first conical plug is coupled to the axial positioning device and is movable in and out of the first conical inner portion along the axis of the test cell. A fluid inlet is positioned at a first location on the test cell and a fluid outlet at a second location.

Abstract: A pressure vessel having a cell with a locking pin, and a cap and associated methods and systems. The locking pin may be configured to engage the cap when the pressure vessel is pressurized to prevent rotation of the cap without depression of the cap.

Abstract: A pressure vessel having a cell with a locking pin, and a cap and associated methods and systems. The locking pin may be configured to engage the cap when the pressure vessel is pressurized to prevent rotation of the cap without depression of the cap.

Abstract: The invention relates particularly to methods and apparatuses for characterizing water-in-oil or invert emulsion fluids for use in drilling well bores in hydro-carbon bearing subterranean formations. A fluid stability measurement device is disclosed. The device comprises a reference electrode and a second electrode coupled to an insulating body. A guard electrode is placed in the path between the reference electrode and the second electrode on the surface of the insulating body.

Abstract: The present invention provides variable density fluid compositions and methods for using such compositions in a subterranean formation. One exemplary embodiment of the variable density fluid compositions of the present invention comprises a variable density fluid comprising: a base fluid, and a portion of variable pressure weighting material particles.

Abstract: The invention relates particularly to methods and apparatuses for characterizing water-in-oil or invert emulsion fluids for use in drilling well bores in hydro-carbon bearing subterranean formations. A fluid stability measurement device is disclosed. The device comprises a reference electrode and a second electrode coupled to an insulating body. A guard electrode is placed in the path between the reference electrode and the second electrode on the surface of the insulating body.

Abstract: Methods for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid are disclosed, as well as compositions for use in such methods. The methods employ drilling fluids comprising fragile gels or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluids are especially advantageous for use in offshore wells because the fluids exhibit minimal differences between downhole equivalent circulating densities and surface densities notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluids, the fluids make environmentally acceptable and regulatory compliant invert emulsion drilling fluids.

Abstract: Methods for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid are disclosed, as well as compositions for use in such methods. The methods employ drilling fluids comprising fragile gels or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluids are especially advantageous for use in offshore wells because the fluids exhibit minimal differences between downhole equivalent circulating densities and surface densities notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluids, the fluids make environmentally acceptable and regulatory compliant invert emulsion drilling fluids.

Abstract: Methods for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid are disclosed, as well as compositions for use in such methods. The methods employ drilling fluids comprising fragile gels or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluids are especially advantageous for use in offshore wells because the fluids exhibit minimal differences between downhole equivalent circulating densities and surface densities notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluids, the fluids make environmentally acceptable and regulatory compliant invert emulsion drilling fluids.

Abstract: Methods for drilling, running casing in, and/or cementing a borehole in a subterranean formation without significant loss of drilling fluid are disclosed, as well as compositions for use in such methods. The methods employ drilling fluids comprising fragile gels or having fragile gel behavior and providing superior oil mud rheology and overall performance. The fluids are especially advantageous for use in offshore wells because the fluids exhibit minimal differences between downhole equivalent circulating densities and surface densities notwithstanding differences in drilling or penetration rates. When an ester and isomerized olefin blend is used for the base of the fluids, the fluids make environmentally acceptable and regulatory compliant invert emulsion drilling fluids.

Abstract: The present invention provides variable density fluid compositions and methods for using such compositions in a subterranean formation. One exemplary embodiment of the variable density fluid compositions of the present invention comprises a variable density fluid comprising: a base fluid, and a portion of variable pressure weighting material particles.

Abstract: Methods and apparatus are provided for reducing heat transfer to or from a fluid contained within double-walled conduit. A method for reducing the heat transfer from a fluid contained within double-walled conduit includes providing an inner conduit, the inner conduit substantially containing the fluid; providing an outer conduit, the outer conduit substantially surrounding the inner conduit; and connecting the inner conduit to the outer conduit via at least one elongated conduction pathway so as to reduce the heat transfer from the fluid.