Abstract: Improved methods and apparatus for completing an unconsolidated subterranean zone penetrated by a wellbore are provided. The methods basically comprise the steps of placing a slotted liner having an internal sand screen disposed therein in the zone, isolating the slotted liner and the wellbore in the zone and injecting particulate material into the annuli between the sand screen and the slotted liner and the slotted liner and the wellbore to thereby form packs of particulate material therein to prevent the migration of fines and sand with produced fluids.

Abstract: An apparatus for attaching a sand-control screen jacket to a base pipe comprising a base pipe connector securably engaged with the sand-control screen jacket. The base pipe connector having a plurality of protrusions for mechanically securing the base pipe connector to the base pipe thereby securing the sand-control screen jacket to the base pipe. The base pipe connector may further comprises a plurality of sealant ports through which sealant is injected affecting an additional seal between the base pipe connector and the base pipe. The sealant ports may accept a lock pin therein after sealant is injected.

Abstract: An apparatus for attaching a sand-control screen jacket to a base pipe comprising a base pipe connector securably engaged with the sand-control screen jacket, an internal slip member slidably disposed between the base pipe connector and the base pipe and a jam nut securably engaging the base pipe connector such that the internal slip member slides toward the base pipe connector increasing the friction between the internal slip member and the base pipe, thereby securing the sand-control screen jacket to the base pipe. The base pipe connector may further comprises a plurality of sealant ports through which sealant is injected affecting an additional seal between the base pipe connector and the base pipe. The sealant ports may accept a lock pin therein after sealant is injected.

Abstract: A well screen for placement within wells used to filter out impurities from the fluid entering the well. In the preferred embodiment, the well screen comprises a spirally-wound wire forming a cylinder with gaps between the layers of wire. The layers of wire are attached by spacers placed within the gaps and on the surfaces of the wire such that the spacers do not extend radially beyond the inner and outer edges of the wire, and thus, forming a flush inner and outer well screen surface. The outer edge of the spacer can be slightly recessed from the outer edge of the wire to create greater open area for which fluid can flow through. In the alternate embodiment, the well screen comprises a plurality of rings stacked atop each other and connected together by spacers located at intervals around the circumference of the rings. The spacers are attached to the wire or rings by a secure means such as welding which results in a single unitized screen that is structurally rigid.

Abstract: An isolation system is disclosed which includes a production screen and an internal isolation pipe sealed with the production screen at proximal and distal ends, and an internal sleeve slideably coupled with the isolation pipe. The isolation pipe defines at least one port and the sleeve defines at least one aperture, and the sleeve is moveable between an open position in which the port and aperture are in communication to permit fluid flow therethrough, and a closed position in which the port and aperture are not in communication and fluid flow is prevented. The sleeve is manipulated by a service string and multi-action shifting tool between the opened and closed positions. Also disclosed is a gravel packer and method of operation incorporating the isolation system, as well as a service tool and service string assembly useful therewith.

Abstract: For the induction of underground collector mains, in particular for the ctruction of horizontal filter wells and drainage mains, at least one bore (1) having respectively an inlet aperture (3) and an outlet aperture (4) is introduced into predetermined layers of soil. Then a filter strand drawing in unit (5) which consists of an inner filter strand and an outer protective pipe is inducted into the respective bore (1) and finally the outer protective pump of the filter strand drawing in unit (5) is removed. The filter strand in unit is used as a tool consisting of an inner filter strand and an outer protective pipe. In a preferred further development, the intermediate space between the inner filter strand and the outer protective pipe is provided with filter sand and/or a filter gravel filling.

Abstract: A well screen for gravel-packing a wellbore interval comprising at least two joints connected by a well tool. Each joint is comprised of a length of screen section which has at least one, axially-extending shunt conduit thereon for carrying gravel slurry to different levels within the interval. The well tool has at least one by-pass tube therein which is adapted to align with and fluidly-connect the shunt conduits on respective joints whereby gravel can flow from one of the shunt conduit, through the by-pass tube, and into and out of the other shunt conduit. A packing means is mounted on the tool for preventing any substantial annular, axial flow past the tool when the tool is an operable position within the wellbore.

Abstract: A well screen for use in gravel packing completions which produces a good distribution of gravel over the entire completion interval. The screen is comprised of a base pipe and an outer surface (e.g. wire wrap). A plurality of flow paths (e.g. shunt tubes) are positioned in the annulus which is formed between the base pipe and the outer surface of the screen, thereby providing the necessary alternate flowpaths for the slurry without substantially increasing the overall, effective outside diameter of the screen.

Abstract: A method and apparatus is described for anchoring a well screen on a stainless steel perforated mandrel without the use of welds in which cup-shaped members, each having a base and an annular wall, are positioned on the mandrel at each end of the screen with the walls of the cups extending partly over the screen and filling the annular cavities between the walls of the cups and the ends of the screen with a liquid adhesive epoxy to anchor the cups to the mandrel.

Abstract: A maintenance screen for use in low-velocity, shallow or horizontal or slightly inclined wells is disclosed. The maintenance screen of the present invention utilizes a generally downwardly oriented portion through which fluid can pass and a generally upwardly oriented portion which does not allow sand or fluid to pass therethrough, so that sand naturally gravitates downward through the fluid and away from the portion of the screen through which the fluid may pass to enter the well tubing.

Abstract: The claimed apparatus is a bottom hole choke device for regulating the flow within gas and oil producing wells. The apparatus includes a screen for preventing sand from entering the production string, a flow-restricting choke, and a check valve for preventing back flow into the well.

Abstract: Method of completing an uncased section (10) of a borehole (1) in an underground formation (2) comprising the steps of:(a) placing at a predetermined position in the borehole (1) a slotted liner (11) provided with overlapping longitudinal slots (12);(b) fixing the upper end of the slotted liner (11); and(c) moving upwardly through the slotted liner (11) an upwardly tapering expansion mandrel (15) having a largest diameter which is larger than the inner diameter of the slotted liner (11).

Abstract: A sand control screen installation for a well includes an auger type sand control screen connected to a length of smooth-walled tubing which is disposed in a tubing seal support sub connected to a packer and having a frangible coupling interconnecting the tubing with the sub whereby the assembly may be pre-installed in a wellbore, the packer set and the tubing decoupled from the sub for reciprocation relative thereto while a fluid tight seal is maintained between portions of the wellbore to prevent underbalanced or overbalanced fluid flow during installation of the sand control screen. In an alternate embodiment, the tubing seal support sub has suitable lock mechanism for installation in a landing nipple in wells with pre-installed tubing strings and packers.

Abstract: A prepack well screen assembly for separating particulate material from formation fluid has inner and outer screens concentrically mounted in radially spaced relation around a perforated mandrel, thereby defining a prepack annulus in which a plurality of spherical plastic members are disposed. The concentric inner screen includes longitudinally extending rib wires spaced circumferentially around the mandrel, and a screen wire wrapped externally about the rib wires in a longitudinally spaced pattern to define spaced screen apertures for conducting formation fluids through the inner screen. The outer screen is a cylindrical fluid-porous, particulate-restricting member which is radially spaced from the inner screen to form the prepack annulus. The particulate-restricting member includes rib wires which are spaced circumferentially around the inner screen within the prepack annulus, and an outer screen wire wrapped externally about the rib wires to define the annulus.

Abstract: A gravel pack screen assembly includes a bit or sub having a flow passage which may accept a wash pipe. The wash pipe may be inserted past a flapper-type closure member which moves to a closed position upon withdrawal of the wash pipe after completion of the installation of the gravel pack assembly. The closure member can be formed of a porous material to permit the flow of liquid through the bit or sub flow passage into the interior of the gravel pack screen but to prevent flow of gravel packing or produced sand into the interior of the screen. The closure member may serve as a backup to a conventional one-way valve and permit additional gravel pack material to be placed in the flow passage upon completion of the gravel pack installation and in the event of early or late failure of the one-way valve.

Abstract: Sand control screens temporarily plugged with paraffin wax are installed in deep open hole wells wherein the wax has a melting temperature slightly greater or less than the nominal formation temperature in the zone from which well fluids are to be produced. Drilling fluids and other solids-laden wellbore fluids are removed from the wellbore by flowing the well up through a section of tubing disposed distal of the screen, through the interior of the screen and through the tubing string to the surface until the wellbore is cleaned. The wax is then melted due to the temperature of the produced fluid, is dissolved by the produced fluid or a solvent pumped down through the tubing string or is heated by a heater inserted into the interior of the screen such as a wireline conveyed electric heater. The distal tubing section is plugged so that production fluids are forced to flow through the sand control screen in a conventional manner.

Abstract: The invention provides a novel apparatus and method for removing liquid contaminant from a well to decontaminate a contaminated aquifer. The apparatus includes a pump capable of moving water and contaminant from below ground surface to a location above ground surface, a motor connected to drive the pump and means connected to power the motor. A water and contaminant inlet are located between the pump and the motor to accept inward flow of water and contaminant to the pump. An outlet pipe connects to the pump and extends above ground surface. A sleeve surrounds the inlet and connects between the inlet and the motor and has an opening to receive water and contaminant. The sleeve is sized to slide in and out of the well and is larger than the outlet pipe. The sleeve creates an annular space around the outlet pipe to permit passage of water and contaminant from the open end to the inlet.

Abstract: A method and apparatus for gravel packing an interval of a wellbore wherein a permeable screen having a means for restricting fluid flow from the annulus into the upper portions of the screen is positioned adjacent the wellbore interval. The flow-restrictive means may be comprised of any material which remains substantially solid during circulation of the gravel slurry but preferably is a material that can be removed, e.g. by melting or dissolving, after the gravel has been placed. Examples of such material are (1) blends of waxes; (2) eutectic compounds formed by combining organic compounds; (3) salts; and (4) asphaltenes which are soluble in crude oil. The flow-restrictive means also may be formed of a perforated metal sleeve which is dissolvable by acid.

Abstract: A positioning tool is combined with a completion tool, for example a sand screen, for positioning the completion tool substantially within the lower half of a horizontal well casing member, and for automatically orienting the working face of the completion tool with respect to a predetermined sidewall portion of the well casing member. The orienting tool includes an annular roll collar which supports the completion tool off of the bottom of the horizontal well casing member, and a pair of radially projecting orienting vanes which limit rolling movement by engaging the upper bore of the well casing member.

Abstract: A method and device for removing sand from hydrocarbonaceous fluids whereby a berm is formed adjacent to a slot which has penetrated a liner or perforated tube. The berm which is formed along each side of said slot operates to form a lip or platform so as to provide a solid base upon which to form a sand bridge to more effectively remove sand from hydrocarbonaceous fluids produced from the well.

Abstract: In a well with filter tube and filter gravel fill a slot profile for a collection element forming the suction tube has larger suction cut-outs at the bottom than at the top and effects an equalization of the flow velocity of the water passing into the filter gravel layer on the basis of the combination of calculations and empirical investigations.

Abstract: A well screen centralizer with a longitudinal flow passage therethrough which has a well screen insert that increases the producing area of the well screen by reducing the amount of blank non-producing tubing length usually used to accommodate non-well screen insert centralizers. A method for constructing a well screen centralizer and a method for inserting well screens into a well bore that includes welding the couplings to the well screens and using a well screen assembly and support stand.

Abstract: A well screen centralizer with a longitudinal flow passage therethrough which has a well screen insert that increases the producing area of the well screen by reducing the amount of blank non-producing tubing length usually used to accommodate non-well screen insert centralizers. A method for constructing a well screen centralizer and a method for inserting well screens into a well bore that includes welding the couplings to the well screens and using a well screen assembly and support stand.

Abstract: A Wellbore sand control and filtration system, method, and apparatus for controlling formation sands and for preventing the influx of formation sands into the wellbore, into the production string, and into the produced fluids, the system including introducing smooth particles into the wellbore with limited or no pumping either of particles or of fluids with the particles, introducing the production string into the wellbore with the bottom of the string being introduced into the accumulation of smooth particles, the bottom of the string having connected thereto a tool permitting flow of formation fluids into the production string, the tool moving into the accumulation of particles forcing particles into the perforation tunnels extending from the annulus through the casing and cement into the formation. The system, method, and apparatus may also be used in an open uncased uncemented hole. A tool is provided for facilitating the movement of the string through the particles.

Abstract: A suction control tail for use with the water pump to restrict water velocities in a well hole and thereby prevent the instrusion of sand is provided by a two-layer suction control element, or such an element in combination with a single-layer suction control element. Each of the two elements has a porous, permeable sidewall, is open at the bottom to admit water and any suspended sand particles, and is open at the top to hydraulically couple the element to a pump inlet or to the base of another element. The two-layered element is formed by a relatively rigid PVC tube with a multiplicity of opening therethrough and an outer porous, permeable layer over the openings formed by bonded granular PVC particles, the single layer element is formed by a similar, relatively rigid PVC tube having a multiplicity of uniform openings therethrough of diminishing cross-sectional area so as to control water velocities into the element.

Abstract: Well screen assembly for permitting a plurality of pipe based well screen segments in an extended length production zone to be brought into operation simultaneously uses a ported connector sub to join each pair of screen segments so that the ends of the relatively large diameter perforated pipe base supports are attached to the connector's ends. Each screen also has solid internal pipe members of much smaller diameter which are joined to a central bore in the connector. Annular spaces between the internal pipe members and the pipe base supports communicate through the connector ports and permit flow from both screens to reach the inside of the inner pipe members when downhole perforations are made in only one of the inner pipe members.

Abstract: A mud screen for installation between any two selected ends of interconnected pipes, such as a drill pipe string, comprises a supporting collar anchored in the selected threaded connection of the drill pipe string and a screen support mounted on such collar and secured thereto by one or more releasing devices. An apertured inverted conical screen is supported by the screen support in transverse relationship to the pipe bore. A bridging element is secured across the screen support and defines a mounting for an upstanding post which functions as a manual handle and also defines a fishing neck at its upper end for downhole retrieval.

Abstract: Economical plastic well screens having good hydraulic performance can be produced by the method of the present invention wherein a sheet having a large plurality of V-shaped slots is injection molded, is roll-formed into a cylindrical shape, and then has its longitudinal edges bonded to each other. The resistance of the screen to collapse and tensile forces can be enhanced by the addition of ribs in one or two directions. Also, the sheet can be rolled in one direction or another to vary the slot direction or to permit flow from inside to outside as well as the conventional outside to inside.

Abstract: Fittings and methods for manufacturing fittings for piping are disclosed. The fittings are assembled from three identical molded pieces joined along longitudinal edges. Interfitting pieces form the joints between the sections and serve to draw the sections together during assembly and ensure roundness of the fitting. The technique is especially useful for the manufacture of fittings such as well screens, of synthetic polymeric materials.

Abstract: A perforated pipe and method of making the same for use in wells, screen and the like, the perforations being in the form of sets of oppositely disposed slits in a tubular member defined along a helical path; the preparation being characterized as self-cleaning and resulting from a balanced forming operation to substantially reduce warpage.

Abstract: Plastic well screen has tapered, undercut slots formed by a laser beam focused through a lens having its focal point located at or slightly away from the surface of the plastic cylinder being slotted so that the laser beam diverges as it passes through the plastic. The cylinder is rotated and simultaneously moved axially relative to the laser beam to produce a series of transverse slots. In one embodiment, the laser beam is interrupted to provide continuous longitudinal support portions in the cylinder. In a modified embodiment, the cylinder has integral internal ribs which remain intact even though the laser is operated continuously to remove surface material located between the ribs and the laser beam.

Abstract: A trap to catch knockout plugs or "pins" from casing inflation packers. The trap is mounted in the well casing above a float valve, and catches pins falling from casing inflation packers in the casing above it as these pins are broken off by a cementing plug descending into the well, thus preventing the loose pins from jamming the float valve open after cementing is completed. The trap comprises a generally cylindrical hollow body having rods extending laterally across its bore, and a collapsible pin guide mounted on top of the body to guide the pins into the body, where they are constrained above the float valve by the rods.

Abstract: The recovery of petroleum produced from an oil reservoir is enhanced by injecting water such as from a geopressured aquifer having a natural gas content at or near saturation at a temperature above 300.degree. F. into the oil reservoir at a flow rate sufficient to develop a back-pressure in the oil reservoir equal to between about 80% of its fracture pressure and a pressure below its fracture pressure and producing oil from the oil reservoir when the injection of water necessary to maintain the back-pressure below the oil reservoir fracture pressure drops below a predetermined level. The recovery of petroleum also is enhanced by using sand screening means to complete a portion of the well bore penetrating into the oil reservoir and a straddle packer assembly means which can be raised and lowered relative to the screening means.

Abstract: Plastic well screen has tapered, undercut slots formed by a laser beam focused through a lens having its focal point located at or slightly away from the surface of the plastic cylinder being slotted so that the laser beam diverges as it passes through the plastic. The cylinder is rotated and simultaneously moved axially relative to the laser beam to produce a series of transverse slots. In one embodiment, the laser beam is interrupted to provide continuous longitudinal support portions in the cylinder. In a modified embodiment, the cylinder has integral internal ribs which remain intact even though the laser is operated continuously to remove surface material located between the ribs and the laser beam.

Abstract: Fittings and methods for manufacturing fittings for piping are disclosed. The fittings are assembled from three identical molded pieces joined along longitudinal edges. Interfitting pieces form the joints between the sections and serve to draw the sections together during assembly and ensure roundness of the fitting. The technique is especially useful for the manufacture of fittings such as well screens, of synthetic polymeric materials.

Abstract: A well screen and method for its manufacture are disclosed. The well screen is assembled from molded parts. The parts are initially formed with a continuous, imperforate outer skin. Continuous circumferential slots are cut in the skin to form a foraminous screen. Integrally formed annular ribs located between each slot provide crush resistance.

Abstract: A well liner for a subterranean well is provided comprising an elongated tubular member which may be a wire wrapped screen having a plurality of slots or passages which are disposed longitudinally and circumferentially of and extending from the outer surface to the inner surface of the tubular member, and an impermeable inorganic matrix substantially filling said slots or passages and coated upon said inner and outer surfaces, said matrix being the reaction product of a first reactant consisting essentialy of magnesium oxide and a second reactant consisting essentially of magnesium chloride, in a solvent or solution therefor.

Abstract: A water screen displaying a variable filtration feature is provided wherein the water screen comprises a pipe length made of a compressible plastic material. The pipe length is provided with a plurality of inlet openings thereby permitting fluid located peripheral to the exterior surface of the pipe length to be transported through the inlet openings and at the same time filtering particulate matter and debris from the water.

Abstract: An improved conventional type of gas lift valve and mandrel combination. It has a large area screen which encloses the valve and prevents it from having the inlet port and/or its integral small area screen, become plugged.

Abstract: Wellhead flow control apparatus for controlling the flow of fluids from a well producing fluids and debris including a novel device for separating and accumulating the debris. The device comprises an outer shell defining an enclosed accumulation chamber, a perforated outlet conduit communicating with the chamber to allow the passage of fluids but prevent passage of debris, and access means to facilitate periodic removal of the accumulated debris. The wellhead apparatus is especially useful for flow control of fluids from geothermal steam wells.

Abstract: A perforated liner is sealed at longitudinally spaced intervals with a removable sealant. The partially sealed liner maintains sufficiently high fluid flow velocity outside the liner during gravel packing so as to prevent the formation of gravel dunes. After packing is completed, the sealant is removed permitting the passage of fluids through the liner.

Abstract: A well tool having an hydraulically releasable coupler component, a gravel packing apparatus and method for use therewith in a subterranean well having production tubing inserted therein, wherein said coupler comprises hydraulic means for releasing the tubing from the gravel pack apparatus without rotating said tubing when the coupler is activated and the tubing removed, the lower portion of the coupler remaining in the well with the gravel pack and providing a receptacle for a packing element partially inserted therethrough.