Abstract: A technique provides a system and methodology for treating a plurality of zones, e.g. well zones. A plurality of flow control devices is located along a tubular structure, such as a well string in a wellbore. Each flow control device or each set of flow control devices comprises a seat member having a unique profile relative to the profiles of the other flow control devices. Drop objects are designed with engagement features arranged to engage the profiles of specific flow control devices. For example, each drop object may have an engagement feature of a corresponding profile designed to engage the unique profile of a specific flow control device or of a specific set of flow control devices to enable actuation of the specific flow control device or the specific set of flow control devices once the drop object is dropped through the tubular structure.

Abstract: Flow control devices can include functionalized surfaces on inner regions of walls. A functionalized surface can include a hydrophilic and/or a hydrophobic material that can affect fluid flowing in a flow path of a wall to facilitate fluid selection by the flow control device. Fluids may be switched in a flow control device using a functionalized surface even when a density and viscosity of different oil and water mixtures of the fluids are the same.

Abstract: A dart launcher launches a dart by placing the dart within a launcher bore formed within a launcher body. The launcher body also defines a central bore coupled inline with a tubing string and in fluid communication with the launcher bore. The launcher bore is formed at an angle to the central bore. A release assembly is coupled to the launcher body and includes a release rod protruding into the launcher bore to selectively release the dart. A visual indicator assembly is coupled to the launcher body downstream from the release assembly and includes a flapper protruding into the launcher bore. The release assembly is actuated by the dart rotating the flapper to rotate an arm from a non-released position to a released position.

Abstract: A universal dart launcher launches a dart by moving a dart from a first position to a second position. The universal dart launcher has a launcher body defining a central bore having an axis and lower and upper ends configured to attach to a string of pipe. A cartridge housed within the launcher body may move perpendicular to the axis from a first position to a second position. A drop member is positioned within the cartridge so that it will not be in axial alignment with the central bore while in the first position, and will be in axial alignment with the central bore while in the second position. An actuator assembly couples to the launcher body to move the cartridge from the first position to the second position when actuated.

Abstract: Herein disclosed is a frac ball comprising three orthogonal axes x, y, and z; wherein the frac ball has approximately equal strength in each direction of the three axes x, y, and z. In an embodiment, the frac ball comprises a resin. In an embodiment, the frac ball comprises glass fibers or carbon fibers or both. In an embodiment, the frac ball comprises an equal amount of glass fibers in each direction of the x, y, and z axes. In an embodiment, the frac ball comprises glass fibers in the x and y axes and carbon fibers in the z axis. In an embodiment, the frac ball comprises no interlaminar layers. In an embodiment, the frac ball has different diameters. Also disclosed herein are methods of making and using such frac balls.

Abstract: A technique that is usable with a well includes deploying a plurality of location markers in a passageway of the well and deploying an untethered object in the passageway such that the object travels downhole via the passageway. The technique includes using the untethered object to sense proximity of at least some of the location markers as the object travels downhole, and based on the sensing, selectively expand its size to cause the object to become lodged in the passageway near a predetermined location.

Abstract: An apparatus for successively releasing balls into a wellbore during wellbore operations is disclosed. The apparatus has a radial housing having at least one radial ball array having two or more radial bores. Each radial bore houses a ball cartridge adapted to receive and release balls and an actuator for operably aligning or misaligning the ball cartridge with an axial bore in fluid communication with the wellbore. The ball cartridge is moveable along the radial bore and is operable between an aligned position, for releasing a ball and a misaligned position for storing the ball.

Abstract: A lost circulation material and method for well treatment employing the material that is effective at sealing or plugging small fissures and large fractures and has utility over a wide range of temperatures, including high temperatures. The material has an optimized bimodal particle distribution and optionally has a polymer flocculent or water swellable polymer.

Abstract: An apparatus for successively releasing balls into a wellbore during wellbore operations is disclosed. The apparatus has a radial housing having at least one radial ball array having two or more radial bores. Each radial bore houses a ball cartridge adapted to receive and release balls and an actuator for operably aligning or misaligning the ball cartridge with an axial bore in fluid communication with the wellbore. The ball cartridge is moveable along the radial bore and is operable between an aligned position, for releasing a ball and a misaligned position for storing the ball.

Abstract: A method is disclosed for controlling the flow of fluid between a downhole formation and a base pipe located in wellbore proximate the downhole formation. A plurality of chokes are established between the formation and the base pipe to regulate the flow of fluid between the formation and the base pipe. In one embodiment, each choke comprises a nozzle formed in the base pipe. In another embodiment, each choke comprises a nozzle in a housing arranged on the base pipe. A plurality of plugs are pumped downhole for engagement with the nozzles. The pressure in the wellbore is then increased until the plugs engage each nozzle. In an alternative embodiment, plugs are pumped downhole and stop up the housing containing the nozzles. Fluid flow between the base pipe and the downhole formation may be reestablished by dissolving the plugs or by back-flowing the production string to dislodge them.

Abstract: Methods and compositions that include a method of treating a subterranean formation comprising the steps of providing a carrier fluid comprising degradable balls that comprise a carboxylic acid, a fatty alcohol, a fatty acid salt, a fatty ester, a fatty acid salt, or a combination thereof, and introducing the carrier fluid to the subterranean formation during a treatment.

Abstract: An example of a method includes providing a hydrajetting tool in a well bore in a formation; injecting a fluid through the tool into a first region of the formation at a velocity sufficient to form one or more perforation tunnels; maintaining the flow of fluid into the perforation tunnels at a pressure greater than the fracture closure pressure, so as to create one or more fractures in the first region; plugging at least partially the fractures with an isolation fluid; injecting a fluid through the hydrajetting tool into a second region of the formation at a velocity sufficient to form one or more perforation tunnels in the second region; and maintaining the flow of fluid into the perforation tunnels in the second region at a pressure greater than the fracture closure pressure, so as to create one or more fractures in the second region.

Abstract: Described is an oil-degradable ball sealer for use in the oil and gas industry. The ball seal comprises a particular composition including ethylene and one or more alpha-olefins, prepared by an injection molding technique to provide a ball sealer which will dissolve in stimulation or wellbore fluids after stimulation operations are complete. The composition, when dissolved into wellbore fluids, does not pose a hazard or problem to aqueous wellbore fluids or further wellbore stimulations.

Abstract: In downhole treatments in the oilfield, ball sealers seated in perforations may not fully seal and may leak fluid through gaps and asperities between the balls and the perforations. A method is given for improving the sealing of ball sealers in perforations by adding a sealing agent that forms a plug in the gaps and severely restricts or eliminates fluid flow. The sealing agent is preferably degradable or soluble, malleable fibers slightly larger than the gaps. Optionally, the particles may be non-degradable, rigid, of different shapes, and smaller than the gaps but able to bridge them. Mixtures of sealing agents may be used. The sealing agent may be added with the ball sealers, after the ball sealers, or both.

Abstract: A multilayered ball sealer having a deformable layer. The multilayered ball sealer has an outer or intermediate layer that is deformable under pressure. In the former, the deformable layer may be water-soluble or hydrolysable. In the latter, the outer layer is a sheath that contains the deformable layer and adapts to its shape. A multilayered ball sealer may be used as a diversion agent by being suspended in a fluid injected into a wellbore and applying pressure to deform the shape of the intermediate layer such that the multilayered ball sealer adapts to the shape of a perforation opening on which the multilayered ball sealer has seated.

Abstract: The present invention is directed to a method of isolating hydrajet stimulated zones from subsequent well operations. The method includes the step of drilling a wellbore into the subterranean formation of interest. Next, the wellbore may or may not be cased depending upon a number of factors including the nature and structure of the subterranean formation. Next, the casing, if one is installed, and wellbore are perforated using a high pressure fluid being ejected from a hydrajetting tool. A first zone of the subterranean formation is then fractured and stimulated. Next, the first zone is temporarily plugged or partially sealed by installing an isolation fluid into the wellbore adjacent to the one or more fractures and/or in the openings thereof, so that subsequent zones can be fractured and additional well operations can be performed.

Abstract: Method for hydraulic fracturing of wells by transporting a cross-linked polymer containing a proppant down a wellbore in a carrier fluid, allowing the cross-linked polymer to coalesce into a polymer phase and squeezing the cross-linked polymer as a fracturing fluid is provided. Composition of the cross-linked polymer solution and the selection of additives may be varied to adjust the viscosity, degradation time and other properties of the fracturing fluid.

Abstract: A technique that is usable with a subterranean well includes orienting shaped charges of a perforating gun to extend partially around a longitudinal axis of the gun. The perforating gun is oriented in the well to direct the shaped charges away from a water boundary. In response to this orientation of the perforating gun, the shaped charges are fired. The perforating gun and shaped charges may also be oriented in a deviated well to compensate for the anisotropic permeability of a formation.

Abstract: A low molecular weight, high melting point, crystalline, oil soluble additive for use in wellbore fluids is provided that is preferably a ground crystalline material of melting point over 80° C., preferably over 100° C. which is readily soluble in produced hydrocarbons such as crude oil and lighter condensates, and which exhibits a molecular weight of less than 1000, and preferably less than 500, and more preferably less than 300. Its particle size can be adjusted to bridge efficiently across different pore size formations and control its solubility rate.

Abstract: A composition for sealing porous subterranean formations comprises a mixture of a water-swellable clay and a water insoluble, water absorbent, water-swellable polymer, wherein the mixture is coated with a material that is resistant to penetration by water. The water penetration resistant material helps the delay the onset of swelling of the clay and polymer until it reaches the formations intended for sealing. Mixing the clay with the water-swellable polymer prior to coating assists in coating of the water-swellable polymer with the water penetration resistant material. The coated mixture can be suspended in an aqueous liquid, and then pumped into a subterranean cavity to seal porous formations therein.

Abstract: This invention provides a method for treating multiple intervals in a wellbore by perforating at least one interval then treating and isolating the perforated interval(s) without removing the perforating device from the wellbore during the treatment or isolation. The invention can be applied to hydraulic fracturing with or without proppant materials as well as to chemical stimulation treatments.

Abstract: This invention provides a method for treating multiple intervals in a wellbore by perforating at least one interval then treating and isolating the perforated interval(s) without removing the perforating device from the wellbore during the treatment or isolation. The invention can be applied to hydraulic fracturing with or without proppant materials as well as to chemical stimulation treatments.

Abstract: This invention provides a method for designing a multiple-stage ball sealer-diverted fracture treatment so that only one set of perforations is fractured by each stage of fluid pumped. It further provides a method for predicting the sequencing in which perforated intervals will fracture during treatment.

Abstract: A method and apparatus for treating a long interval within a wellbore wherein a treatment fluid is delivered to selected levels within the interval by blocking flow to certain zones while allowing flow to others. A treatment tube extends substantially through the interval and is comprised of a perforated conduit which is open at its upper end and which has a plurality of openings spaced along its length. Each of the openings have a valve seat within the conduit at its entrance which is adapted to receive a valve to seal and block flow through that opening. In operation, a treatment fluid is flowed through the treatment tube and out the openings into different levels within wellbore. At desired intervals, the valve are introduced into the treatment fluid and are carried into the treatment tube to seat at a respective opening to thereby block flow through that opening while allowing continued flow through others.

Abstract: A method for isolating subterranean formations or zones intersected by a single wellbore is provided. The method comprises perforating a zone intersected by the wellbore and pumping a sealing means into the wellbore to seal against the side of the casing above and below the perforations to prevent communication from the zone into the wellbore after the casing has been perforated. The method further comprises fracturing the zone through the perforations prior to sealing and thus isolating the zone. Other zones thereabove are likewise perforated, fractured, sealed and thus isolated by pumping sealing means into the wellbore to seal the casing adjacent the perforations to prevent communication from the affected zones into the wellbore.

Abstract: A method for stimulating production from wells drilled into natural gas reservoirs characterized by lenticular deposits. The reservoir thickness through which the wells are drilled is divided into multi-stage zones that are further divided into single-stage zones. Each single-stage zone is perforated and then fractured. The fracturing is conducted in multiple stages to sequentially fracture each of the single-stage zones within a multi-stage zone; the fracturing stages being separated by ball sealers. Well spacing may also be controlled to match fracture drainage and size of the lenticular deposits.

Abstract: A method for zone isolation or replacing a damaged or corroded casing with a solid plastic is described herein. A resin/curing agent mixture sufficient to form a hardened plastic or solid, underwater and/or at low wellbore temperatures that is also able to withstand downhole stresses, is placed into the wellbore so as to bind with the undamaged casing and close off any thief zone. Subsequently, the resin/curing agent mixture forms a hardened solid. The hardened solid is milled out if necessary so as to form a resinous casing the size of the original casing. Later, the hardened resinous casing is perforated to communicate with a targeted zone. Perforation is not required when isolating a zone. The hardened solid is of a strength sufficient to withstand stresses generated during EOR operations such as carbon dioxide or steam-flooding. Said solid is also resistant to workover acids and other chemicals used in EOR operations.

Abstract: The invention is a rigid, hollow core, low-density ball sealer designed to perform effectively in hostile well environments. It temporarily seals perforations inside cased wells at temperatures up to 400.degree. F. (204.degree. C.), at hydrostatic pressures up to 20,000 psi (137 Mpa), and at differential pressures across the perforations up to 1,500 psi. Ball densities may range from 0.80 to 1.3 gm/cc (or higher). It can withstand the degradation effects of solvents common to oil and gas wells during a workover. Nominal changes in ball density occur during a 24-hour period when exposed to a hostile well environment. The ball sealer is comprised of two pieces made of a high strength material that snap together to form a hollow-core sphere. If necessary, adjustments to ball density can occur subsequent to manufacturing of the ball pieces.

Abstract: Methods of remedially treating coal bed methane wells to enhance the production of methane therefrom are provided. The methods basically comprise pumping a clean out fluid into the well and into producing zones communicated with the well by perforations therein. The pumping of the clean out fluid is continued while adding perforation sealers thereto to thereby seal perforations and producing zones which are not plugged and to divert the clean out fluid into perforations and producing zones which are partially plugged. An aqueous acid solution is next pumped into the partially plugged perforations and producing zones whereby acid soluble solid materials in the perforations and producing zones are dissolved. The well is shut in, reverse flowed and then returned to production.

Abstract: Ball sealers comprising a polyetheretherketone are introduced into a well to seal well perforations and divert fluid therein. In the preferred embodiment the ball sealers have a density less than the treating fluid.

Abstract: Ball sealers for flowing into casing perforation holes in a wellbore to selectively seal off those perforations receiving a disproportionately large amount of well treatment fluid being injected through the perforations. The ball sealers (22) are comprised of a spherical outer deformable shell (42) defining a central core portion filled with nondeformable particulate matter (46) which is sized small enough to flow with the shape of the deformable outer shell (42) and large enough so that as it consolidates under the force of fluid flow pressure, it will cause the outer shell to bridge over the perforation opening (18) when the force of fluid flowing into the casing (12) pushes the ball sealer (22) against and into the perforation opening (18).

Abstract: An apparatus injects sealing balls into a well in response to closed loop control. The apparatus measures the fluid flow into the well, computes a total amount of fluid which has been introduced into the well, and actuates the release of a sealing ball upon a predetermined amount of fluid being reached. A related method is also disclosed.

Abstract: A method of temporarily reducing fluid loss into a subterranean formation from a well bore penetrating the formation by way of at least one perforation is provided. A first soluble particulate solid material is introduced into the formation by way of the perforation having a particle size whereby it bridges on the face of the formation and fills the perforation but allows fluid flow therethrough. A second soluble particulate solid material is introduced into the well bore having a particle size such that it bridges on the first particulate solid material and forms a seal over the perforation within the well bore.

Abstract: Methods are provided for chemically consolidating subterranean formations around wells using resins. Resins are forced into the formations by high pressures instantaneously applied when perforations are formed in casing in wells or when pressures are released from tubing in wells. Perforating, explosives or gas generators may be used in addition to the high pressures for driving resins into formations. The resins are polymerized to form permeable consolidated zones around wells.

Abstract: A method if disclosed for decreasing the flow resistance of a subterranean formation surrounding a well. A high fluid pressure is suddenly applied to the formation and fluid is pumped into the high pressure fractures. The fluid may contain proppant particles.

Abstract: Gas leakage from oil wells through casing thread connections and other small leakage spaces is reduced or eliminated by injecting into the lift gas flowstream a sealant composition comprising a carrier liquid, such as diesel fuel or water, an ethoxylated phenol surfactant and particulate silica and/or Gilsonite. A liquid sealant composition is injected into oil wells on artificial gas lift comprising arctic diesel fuel, a surfactant and solubilized Gilsonite in a weight ratio of about 10:1 diesel fuel to Gilsonite and diesel fuel to surfactant, respectively. Effective reduction in leakage flow rates is obtained over a relatively short time period (one to ten hours).

Abstract: The present invention provides a reliable, high efficiency perforation breakdown process. The inventive process, which utilizes a treating fluid and ball sealers, can be used in all types of wells. In the inventive breakdown process, the number of perforations existing downhole which have already been opened but have not yet been temporarily sealed is determined from observed wellhead pressures and/or wellhead pressure changes. A treating fluid flow rate is then established such that (i) the treating fluid will continue to flow through the already opened perforations which have not yet been sealed at a velocity which is at least as high as the minimum effective sealing velocity but (ii) maximum safe wellhead pressure will not be exceeded when one or more additional perforations is sealed.

Abstract: The present method of drilling, completing and fracturing enhances the production from any reservoir where artificial lift devices are required. However, this method is most suitable for a low pressure, partially depleted subterranean reservoir (50) where secondary recovery methods have proven unsuccessful, or where virgin drainage and pressure has been depleted. The method comprises drilling a substantially horizontal wellbore (20) which penetrates a subterranean reservoir (50) at a degree sufficient to provide drainage through the total vertical section of the reservoir. The horizontal wellbore (20) intersects a vertical wellbore (10) at the lowest vertical depth reached. Fracture stimulation may be applied from either the vertical wellbore, the horizontal wellbore, or both. Moreover, several horizontal well bores (20) can be drilled from a single surface (a) location to intersect other vertically drilled wells (10) or existing producing wells in a reservoir.

Abstract: A method for stimulating a formation penetrated by a horizontal wellbore where hydraulic fracturing is utilized. The horizontal wellbore casing is perforated on its top side. Thereafter, the formation is fractured through said perforations with a fracturing fluid containing a fused refractory proppant. The density of the proppant selected is equal to the density of the fracturing fluid utilized.

Abstract: Subterranean oil and gas producing formations are fractured at vertically spaced intervals utilizing perforating guns forced down the well casing in tailing off "trains" comprising tamping and spacing water columns respectively positioned above and below each perforating gun, a perforation plugging slurry positioned below the spacing water column, and a concentrated proppant slurry column positioned below the perforation plugging slurry column. The perforation plugging and proppant slurry columns are sealed at their upper and lower ends by specially designed gel plug seals each comprising a short column of strong gel solution in which a spaced pair of casing size rock salt balls are disposed to provide the seal with structural reinforcement.

Abstract: The invention concerns a mechanical system which permits the use of ball sealers as diversion agents in the acidizing of productive hydrocarbon formations, by associating the advantages of mechanical diversion to the advantages of the use of ball sealers, whatever their density.The mechanical system comprises a packer (7), a swivel (18), a centralized tail (9), a ball ejection port (10) and two cups (11).The mechanical system operation involves the adequate positioning of each of its components in such a manner as to permit the ball sealers to attain sufficient velocities to be driven mechanically to their targets.

Abstract: Subterranean oil and gas producing formations are fractured in a first embodiment by providing one or more combustion gas generating units using rocket fuel type propellants disposed in a well casing at preselected depths. The well casing is filled with a compressible hydraulic fracturing fluid comprising a mixture of liquid, compressed gas, and propant material and precompressed to a pressure of about 1,000 psi or more greater than the fracture extension pressure at the depth of the zone to be fractured. At least one of the gas generating units is equipped with perforating shaped charges to form fluid exit perforations at the selected depth of the fracture zone. The gas generating units are simultaneously ignited to generate combustion gasses and perforate the well casing.

Abstract: An improved method for placing ball sealers (25) onto casing perforations (17) in a deviated wellbore (10) is disclosed. In this invention, a plurality of ball sealers (25) are introduced into the casing and are transported to the perforations at an interface (26) between two immiscible fluids; the first or leading fluid (21) having a density greater than the ball sealers and the second or trailing fluid (24) having a density greater than the ball sealers.

Abstract: Plugging perforations in casing in a wellbore penetrating a subterranean formation using degradale ball sealers. The ball sealer used is composed of a polyester polymer which is substantially insoluble in the wellbore fluid. The polymer degrades in the presence of water at an elevated temperature to form small molecules which are soluble in a fluid in the subterranean formation. After the polymer degrades, the flow through the perforation returns to substantially its initial value.

Abstract: A method for diverting CO.sub.2 injection in injection wells by the use of perforation ball sealers composed of polymer compounds covered with a thin coating of elastomer of low enough density to float in the injected fluids, yet able to stand the adverse temperatures of CO.sub.2 injection.

Abstract: A method for diverting steam injection in injection wells by the use of perforation ball sealers composed of polymer compounds covered with a thin coating of elastomer of low enough density to float in the injected fluids, yet able to stand the adverse temperatures of steam injection.

Abstract: A method for modifying the injectivity profile of hydrocarbonaceous formations penetrated by at least one injection well and one production well which formation contains zones of varying permeabilities. Via this method, ball sealers are used to stop fluids from flowing through a zone of greater permeability while a zone of lesser permeability receives a temporary blocking agent. Thereafter, the ball sealers are removed and the zone of greater permeability is closed with a permanent blocking agent. Subsequently, the temporary blocking agent is removed and water flooding is reinstituted leading to improved oil recovery.

Abstract: An improved method is disclosed for remedial cementing operations. Prior to conducting the remedial cementing operation, the zone to be cemented is pretreated with a hydrocarbon solvent capable of dissolving hydrocarbons, such as oils and asphaltenes. Following solvent treatment, the zone may be treated with an acid solution capable of dissolving mineral constituents.

Abstract: The flow of liquid escaping from a leak in a vessel, e.g., a pipeline, is reduced or eliminated by introducing particles into the liquid. The particles are dispersed in a slug of material of higherviscosity than the liquid in the vessel and the size of at least some of the particles is greater than that of the hole. The position of introduction of the slug is such that the slug containing the particles is carried by the liquid to the hole. The particles ar non-deformable so that they lodge in the hole without extruding through at elevated pressure and thereby seal the hole.

Abstract: The present invention relates generally to the composition and method for reducing the permeability of subterranean formations penetrated by a wellbore. The composition of the present invention comprises a wellbore fluid having dispersed therein a fluid loss control agent comprising a polyester polymer which is substantially insoluble in the wellbore fluid. The polymer degrades in the presence of water at an elevated temperature to form small molecules which are soluble in a fluid in the subterranean formation. The method of the present invention comprises reducing the permeability of subterranean formations penetrated by a wellbore by placing the composition of the present invention down the wellbore.