Abstract: Cement compositions containing an expandable material are disclosed. The compositions are suitable for use in oil and gas wells. An example of such an expandable material is a polymer encapsulated chemical that expands upon heating. Examples of cement compositions containing polymer encapsulated isobutane or isopentane are disclosed. The use of cement compositions containing an expandable material can reduce the formation of micro-annulus or other deleterious physical properties in the set cement.

Abstract: A method of fracturing a zone of a subterranean formation penetrated by a well bore is shown in which a gelable fracturing fluid is formed by combining an aqueous base fluid and a hydratable polymer. A transition metal crosslinker is added to the aqueous base fluid for crosslinking the hydratable polymer to form a gelled fluid of sufficient viscosity to facilitate fracturing of the formation. A proppant can also be added to the gelable fracturing fluid. The gelled fluid and proppant are then injected into the well bore and into contact with the formation under sufficient pressure to fracture the formation. The gelable fracturing fluid has incorporated therein a delayed release breaker comprising a complex multivalent chelating agent that is released slowly over a period of time to compete with the polymer for the transition metal crosslinker, thereby reducing the viscosity of the fluid.

Abstract: A well fracturing fluid comprising one or more anionic viscoelastic surfactants and one or more polymers is described. The fluids can contain an aqueous or non-aqueous fluid and/or buffer for adjusting the pH of the fracturing fluid. The well service fluid can used as a fracturing fluid in order to control water production from a well, while simultaneously increasing the oil production from the well.

Abstract: Cement compositions containing low reactivity materials are disclosed. The compositions are useful in conditions involving high temperatures, high pressures, and tectonic forces such as oil and gas wells. The cement compositions display increased compressive strength, flexural strength, and tensile strength. Fractures appear to occur in a non-linear fashion between the Interfacial Transition Zone (ITZ) of the particles, rather than in a straight line such as those observed in conventional cement materials.

Abstract: A fluid filtration system of well workover fluids, the system comprising: a first settling tank which stores fluid; a second settling tank which stores fluid; a low pressure pump in fluid communication with the first and second settling tanks; a low pressure filter in fluid communication with the first and second settling tanks; a high pressure pump in fluid communication with the second settling tank; and a high pressure filter in fluid communication with the second settling tank, wherein the high pressure filter comprises: an inlet; an outlet; a plurality of input feed lines in fluid communication with the inlet; a plurality of output feed lines in fluid communication with the outlet; a plurality of filter canisters, wherein at least one filter canister is in fluid communication with each input feed line and each output feed line.

Abstract: A well service fluid composition comprises a fracturing fluid and a gas hydrate inhibitor. Preferably, the gas hydrate inhibitor does not affect the function of the fracturing fluid and is present in an amount sufficient to control and/or minimize the formation of gas hydrates. The well service fluid composition is useful in hydraulic fracturing in which the composition is injected into a subterranean formation under sufficient pressure to initiate and propagate a fracture in the formation. The fracturing fluid may be subsequently recovered when the fracturing operation is completed.

Abstract: The present invention provides a cementing system and method for wellbores by cementing an annulus between a wellbore casing and a wellbore. In at least one embodiment, the invention includes a landing collar defining a restricted passage, a wellbore casing defining a passage coupled to the landing collar, a top cementing plug for sealingly engaging the wellbore casing, a bottom cementing plug for sealingly engaging the wellbore casing, and a fluid injection assembly coupled to the wellbore casing for injecting fluidic materials into the wellbore casing and controllably releasing the top cementing plug and the bottom cementing plug into the wellbore casing. The bottom cementing plug includes a plug body defining a plug passage, a frangible membrane for sealing the plug passage, and a one-way valve for controlling the flow of fluidic materials through the plug passage. The invention also includes the bottom cementing plug and methods for operation.

Abstract: Methods and compositions useful for controlling sand production from subterranean formations that utilize relatively lightweight and/or substantially neutrally buoyant particles as particulate sand control material.

Abstract: Natural fiber-containing cement compositions for cementing wellbores in high stress and high temperature environments. The cement compositions may contain natural mineral fiber materials such as wollastonite in an amount of greater than about 10% and in an amount selected to be effective to achieve ratios of flexural strength to compressive strength of cured cement that are greater than about 0.35 at downhole temperatures of greater than about 180° F.

Abstract: A string for completing a well, the string having several parts including: a base pipe with a hole; a packer in mechanical communication with the base pipe; a screen in mechanical communication with the base pipe, wherein the screen is proximate the hole in the base pipe; an isolation pipe concentric within the base pipe and proximate to the hole in the base pipe, wherein an annulus is defined between the base pipe and the isolation pipe; and an annular flow valve in mechanical communication with the base pipe and the isolation pipe, wherein the annular flow valve controls longitudinal fluid flow through the annulus.

Abstract: Compositions comprising a base fluid and a monoester copolymer of styrene and maleic anhydride are disclosed. The compositions can further comprise an alkyl orthophosphate ester. The base fluid can be an aqueous or organic base fluid. The monoester copolymer is at least partially soluble or dispersible in the base fluid. Preferably, the composition may further include a cross-linking agent capable of increasing the viscosity of the composition, such as aluminum isopropoxide or other metal source compounds. The composition can form a gel which is stable at a temperature of about 250° F. (121° C.) or higher. Some gels of the present invention exhibit stability up to about 300° F. (149° C.) to 350° F. (177° C.) or higher. The compositions have many applications, such as pipeline treatment, conformance, hydraulic fracturing, well completion, gravel packing, drilling fluids, process facility treatment fluids, and other well treatment applications.

Abstract: A method for cleaning a plugged gravel pack in a subterranean wellbore is provided. The method comprises the steps of using a pressure pulsating jet and a tangential vortex to deliver a pressure pulsating treatment fluid into the gravel pack wherein soluble plugging materials in the gravel pack are dissolved by the treatment fluid and insoluble plugging materials are moved through the gravel pack and circulated out of the wellbore. The treatment fluid is driven more completely into the gravel pack to obtain a greater coverage in the pack to dissolve soluble fines and displace insoluble fines from the interstitial pore spaces of the gravel pack.

Abstract: A dual tubing coiled tubing string, including methods of assembly, that includes an inner tubing sealed within at least an upper portion of an outer tubing.

Abstract: A fluid filtration system of well workover fluids, the system comprising: a first settling tank which stores fluid; a second settling tank which stores fluid; a low pressure pump in fluid communication with the first and second settling tanks; a low pressure filter in fluid communication with the first and second settling tanks; a high pressure pump in fluid communication with the second settling tank; and a high pressure filter in fluid communication with the second settling tank, wherein the high pressure filter comprises: an inlet; an outlet; a plurality of input feed lines in fluid communication with the inlet; a plurality of output feed lines in fluid communication with the outlet; a plurality of filter canisters, wherein at least one filter canister is in fluid communication with each input feed line and each output feed line.

Abstract: A method and apparatus for use in a subterranean well is described. The apparatus typically includes a subterranean plug including a mandrel having an outer surface and a non-circular cross-section and a packing element arranged about the mandrel, the packing element having a non-circular inner surface matching the mandrel outer surface such that concentric rotation between the mandrel and the packing element is precluded. The apparatus may include slips having cavities to facilitate quick drill-out of the plug. The apparatus may include a valve for controlling fluid flow through a hollow mandrel. The apparatus may include a composite mandrel having radial vents that establish fluid communication from within to without the mandrel. Also, the apparatus may include a wire line adapter kit for running the apparatus in a well bore.

Abstract: A method and apparatus for use in a subterranean well is described. The apparatus typically includes a subterranean plug including a mandrel having an outer surface and a non-circular cross-section and a packing element arranged about the mandrel, the packing element having a non-circular inner surface matching the mandrel outer surface such that concentric rotation between the mandrel and the packing element is precluded. The apparatus may include slips having cavities to facilitate quick drill-out of the plug. The apparatus may include a valve for controlling fluid flow through a hollow mandrel. The apparatus may include a composite mandrel having radial vents that establish fluid communication from within to without the mandrel. Also, the apparatus may include a wire line adapter kit for running the apparatus in a well bore.

Abstract: Methods are provided for fracturing subterranean formations using fluids having substantially reduced polymer loadings that have performance equivalent to conventional fluids. Reduced polymer loadings provide significant advantages such as reduced treatment costs and less damage to the fracture sand pack and surrounding subterranean formations.

Abstract: A method and apparatus for use in a subterranean well is described. The apparatus typically includes a mandrel and a packing element. The mandrel may have an outer surface and a non-circular cross-section and a the packing element may be arranged about the mandrel, the packing element having a non-circular inner surface matching the mandrel outer surface such that concentric rotation between the mandrel and the packing element is precluded. The apparatus may include slips having cavities to facilitate removal of the apparatus. The apparatus also may include a valve for controlling fluid flow through a hollow mandrel. The valve may include a flapper having at least one tab to engage at least one recession in the mandrel such that rotation between the mandrel and the valve is precluded when the valve is in a closed position. The apparatus may further include a central member which is releaseably attached to the mandrel by a release mechanism.

Abstract: A method of repairing a section of pipe is described. The method includes applying a first split sleeve and a second split sleeve to the pipe section, functionally associating the first end of the first split sleeve with the first end of the second split sleeve, and applying a compressive force until the internal diameter of the pipe experiences compressive shear hoop strain. The method described produces substantially uniform compressive hoop strain along the length of the pipe section, and may exceed a predetermined value, such as 100 microstrain in compression, for example. The amount of force required may be calculated utilizing maximum operating conditions. The method described may produce an acceptable permanent repair by ensuring that the inner diameter of the section of pipe experiences compressive strain. Also described is a method of reinforcing a section of pipe utilizing these apparatus and methods.

Abstract: Method and Apparatus for gravel packing, cleaning and lifting wells, including through tubing methods, circulating well fluids through a coiled tubing string having a leak protection barrier operable for at least a portion of the string passing above a wellhead and employing a circulating and release sub.