Abstract: A floating apparatus for use in a casing string is provided. The apparatus includes an outer sleeve having a valve centrally positioned therein. A cement body is affixed to the check valve and the housing by use of a bonding material.

Abstract: A pressure transducer comprises a quartz crystal having an orientation within a range of angles between about -25.degree. and about -45.degree. relative to the Z axis of X, Y and Z crystallographic axes. Such a pressure transducer provides a useful pressure response at pressures and temperatures above those of the operating ranges of pressure transducers using AT-cut or BT-cut quartz crystals.

Abstract: The present invention provides a method of treating a subterranean formation utilizing a gelled fluid containing a galactomannan gum and a crosslinking agent comprising a source of borate ions and a delayed crosslinker comprising a source of Ti(+4) or Zr(+4) ions. The combination of crosslinking agents yields a viscous fluid at elevated temperatures having a viscosity higher than attainable by either crosslinking agent alone or as the result of the additive effects of the crosslinking agents. The enhanced viscosity facilitates transport and placement of proppant material in a subterranean formation.

Abstract: This invention relates to a method of repairing holes, channels, voids and microannuli in a cement sheath situated in the annular space between a casing and the wall of a wellbore penetrating a subterranean earth formation, which method involves the use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement, which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.

Abstract: This invention relates to a method of cementing a cylinder in a bore, such as a casing in a wellbore, which method involves the use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.

Abstract: This invention relates to a method of repairing a hole in and thereby terminating the undesirable flow of fluid through a hole in a casing disposed in a wellbore penetrating a subterranean earth formation which method involves the same use of a hydraulic cement consisting of discrete particles having a particle size not greater than about 30 microns. The cement, which is utilized in a water slurry, has a low density, good thixotropic properties and, in one embodiment, expansive characteristics.

Abstract: The invention provides a perforating assembly and a method and apparatus for retaining shaped charges in a charge carrier. A shaped charge body has two clips associated with it: a band clip having a plurality of radially extending tabs oppositely oriented for mounting the shaped charge body in the charge carrier, and for securing the shaped charge body in place; and a wire clip mounted on the shaped charge body and adapted to hold a detonating cord in contact with the shaped charge.

Abstract: A waste solidification composition comprising hydraulic cement, fly ash and fumed silica material is provided. Also provided are a method of solidifying agglomerations of solid and liquid waste materials and a method of disposing of waste materials such as drilling muds and cuttings that result from the drilling of an oil and gas well.

Abstract: A formation control additive is utilized in stimulation fluids to minimize formation permeability damage as a result of formation contact by the stimulation fluid. The formation control additive can comprise N-alkypyridinium halides, N,N,N-trialkylphenylammonium halides, N,N,N-trialkylbenzylammonium halides, N,N-dialkylmorpholinium halides, alkyl quaternary ammonium salt of 2 mole oligomer of epihalohydrin wherein the alkyl radical is selected from the group of methyl, ethyl, propyl and butyl radicals and compounds of the general formula: ##STR1## wherein R is independently a methyl, ethyl, propyl or butyl radical and X is a compatible anion.

Abstract: A method of increasing the production of hydrocarbons from a subterranean formation wherein an undesirable filter cake is present, resulting from the introduction of gelled polysaccharide containing fluids into the formation, comprising contacting the formation with an effective amount of a treatment fluid comprising a soluble source of fluoride ions present in an amount sufficient to provide a molar concentration of from about 0.01 about 0.5, having a pH in the range of from about 2 to about 4, whereby at least a portion of the filter cake is caused to dissolve.

Abstract: A tool for activating the firing head of a perforating gun located below a packer by applying pressure to the upper well annulus while maintaining an unimpeded bore between the perforating gun and the pipe string. The tool is provided with a flow valve to prevent flow through the flow bore when closed, and a circulation valve which permits fluid flow from the upper annulus into the flow bore when open and a means of switching the valves so that when one is open the other is closed. A method of using the tool to complete a well is also disclosed.

Abstract: A protective cover assembly for a fluid end of a plunger-type pump or other positive displacement pump. The protective cover assembly includes a cover adapted to fit in an open end of the fluid end of the pump. The cover comprises a convex or domed center portion adapted for buckling away from a plunger of the pump when pressure in the pump exceeds a predetermined level and further comprises an outer portion. A cover retainer is engageable with the open end of the fluid end of the pump and is adapted for clamping the outer portion of the cover to the fluid end. A seal is provided between the outer portion of the cover and the fluid end. The convex center portion of the cover has a convex surface generally facing the plunger, and the convex surface is preferably hemispherical.

Abstract: Cementing compositions having improved fluid loss capabilities for use in oil, gas, water and other well cementing operations are disclosed. Such compositions are comprised of water, hydraulic cement and a fluid-loss additive comprising a polymerization reaction product consisting essentially of 2-acryl-amido-2-methylpropanesulfonic acid or its salts, present in the product in an amount of from about 30 to about 90 mole percent, styrene present in the product in an amount of from about 5 to about 60 mole percent and acrylic acid or its salt comprising the balance of the product.

Abstract: An annulus pressure responsive sampler valve comprising a power section and a sampler section having an annular sample chamber therein; the sampler valve having a full bore therethrough.

Abstract: A process for treating a subterranean formation with an aqueous cement composition and minimizing damage to formation permeability by said composition filtrate comprising mixing with said composition at least one polycationic polymer having a molecular weight of about 400 to 6,000,000 prior to treating said formation.

Abstract: Particular aqueous gel compositions are described for use as a carrier fluid for gravel, sand or particulate matter for the purpose of gravel packing, fracturing, or propping fractures in a subterrranean well formation.

Abstract: A downhole tool includes inner and outer telescoping cylindrical members. The inner cylindrical member has a cylindrical indexing sleeve disposed thereabout. A groove having a semi-circular cross section is disposed in a cylindrical outer surface of the indexing sleeve. Connected to the outer cylindrical member is an apparatus for holding a spherical ball so that approximately one-half the ball is engaged with the semi-circular cross section groove and the other of the ball is disposed within a radial bore in the outer cylindrical member. Relative movement between the inner and outer cylindrical members is defined by engagement of the spherical ball with the groove. The spherical ball is biased toward the groove by a compression spring or a displaceable fluid under pressure.

Abstract: A method is provided for cementing an annular cavity between a subsea well casing and a borehole from a floating vessel. A drill string is run into the casing. An opening positioner attached to the drill string is engaged with a valve in the casing. The drill string is lifted to open the valve. The drill string is positioned to align an isolation packer with the casing valve. An anchor attached to the drill string is set to provide sufficient resistance between the drill string and the casing to operate a motion compensator on the floating vessel. A cement slurry is then pumped into the drill string, out the isolation packer, through the open casing valve and into the annular cavity between the casing and the well bore-hole.

Abstract: A reverse circulation valve includes a cylindrical housing having an open longitudinal passageway disposed therethrough and a circulating port and a power port disposed through a wall thereof. A valve mandrel is slidably received in the housing and movable from a closed position closing the circulating port to an open position opening the circulating port. The valve mandrel includes an annular piston received in the housing for moving the valve mandrel from its closed position to its open position. The power port communicates the piston with a pressure exterior of the housing. A frangible restraining structure is located between the valve mandrel and the cylindrical housing for restraining movement of the valve mandrel from its closed position to its open position until the pressure exterior of the housing exceeds a predetermined value, and for frangibly releasing the valve mandrel when said pressure exterior of the housing exceeds said predetermined value.

Abstract: A drill pipe tester valve includes a spherical valve member supported from an upward facing surface of a housing so that downward forces exerted on the valve member in its closed position, due to fluid pressure in a string of pipe above the valve member, are transmitted substantially entirely to said housing.