Abstract: A particle control screen assembly for a perforated pipe used in a well, a sand filter system, and methods of making same are provided. The screen assembly includes a woven mesh filter media disposed about an inner surface of the perforated pipe, and a protective wrapper disposed about the filter media. The protective wrapper comprises a radially inner perforated layer and a radially outer layer that is disposed between the inner layer and the filter media. A surface of the outer layer that faces the inner perforated layer has a non-smooth contour, with this surface of the outer layer having portions in direct contact with an outer surface of the inner layer. The outer layer is provided with apertures that are disposed in such a way that fluid cannot flow from the inner surface of the inner perforated layer directly radially both through holes of the inner layer and through the apertures of the outer layer.

Abstract: A particle control screen assembly for a perforated pipe used in a well, a sand filter system, and methods of making same are provided. The screen assembly includes a woven mesh filter media disposed about an inner surface of the perforated pipe, and a protective wrapper disposed about the filter media. The protective wrapper comprises a radially inner perforated layer and a radially outer layer that is disposed between the inner layer and the filter media. A surface of the outer layer that faces the inner perforated layer has a non-smooth contour, with this surface of the outer layer having portions in direct contact with an outer surface of the inner layer. The outer layer is provided with apertures that are disposed in such a way that fluid cannot flow from the inner surface of the inner perforated layer directly radially both through holes of the inner layer and through the apertures of the outer layer.

Abstract: A deformable well screen for preventing migration of solid particles into a hydrocarbon production well is disclosed, the screen including at least one substantially tubular filter layer of which the sieve opening size remains fairly constant during or after expansion and/or other formation of the screen. Optionally the screen also includes a series of circumferentially scaled filter segments that are arranged around an expandable slotted tube, an expandable slotted tube of which the slots are filled with resin coated granules, an expandable slotted tube with micro-slots, an assembly of woven metal wire screens that are sintered together and/or a synthetic geotextile fabric.

Abstract: A particle control screen assembly for a perforated pipe used in a well, a sand filter system, and methods of making same are provided. The screen assembly includes a woven mesh filter media disposed about the perforated pipe, and a protective wrapper disposed about the filter media. The protective wrapper comprises an outer perforated layer and an inner layer that is disposed between the outer layer and the filter media. A surface of the inner layer that faces the outer perforated layer has a non-smooth contour, with this surface of the inner layer having portions in direct contact with an inner surface of the outer layer. The inner layer is provided with apertures that are disposed in such a way that fluid cannot flow from the outer surface of the outer perforated layer directly radially both through holes of the outer layer and through the apertures of the inner layer.

Abstract: A well screen is disclosed for positioning in a well bore to screen solid particles from the fluid produced by the well comprising a base pipe, a portion of the wall of which is perforated, and having threaded connections for connecting the base pipe into a pipe string, a wire screen surrounding the perforated portion of the base pipe, a thin porous membrane comprising two layers of woven cloth of ceramic fibers wrapped around the wire screen, means for holding the ends of the porous cloth membrane in sealing engagement with the base pipe, and a perforated tubular metal shroud surrounding the woven ceramic cloth membrane to protect the membrane from damage when lowered into a well bore.

Abstract: A particle control screen assembly for a perforated pipe used in a well, a sand filter system, and methods of making same are provided. The screen assembly includes a woven mesh filter media disposed about the perforated pipe, and a protective wrapper disposed about the filter media. The protective wrapper comprises an outer perforated layer and an inner layer that is disposed between the outer layer and the filter media. A surface of the inner layer that faces the outer perforated layer has a non-smooth contour, with this surface of the inner layer having portions in direct contact with an inner surface of the outer layer. The inner layer is provided with apertures that are disposed in such a way that fluid cannot flow from the outer surface of the outer perforated layer directly radially both through holes of the outer layer and through the apertures of the inner layer.

Abstract: Gas is separated from well fluid solutions by a hydrophobic membrane GORTEX.RTM. like filter element that is permeable to gas but impermeable to water; the filter element, which may include a solids prefilter, is positioned within the well bore containing water or well fluids at a depth where the hydrostatic pressure will allow the gas to bubble out of solution.

Abstract: A filter is provided which combines a woven wire mesh over a supporting body. The supporting body is typically a metal perforated tube which provides fluid communication between the well bore and the production equipment string. The woven wire mesh acts as a filter to prevent the influx of sand particles, provides openings oriented at various angles relative to its surface, so that some area is available for fluid entry even when particulate matter is lodged on the surface above an opening, provides interior channels that allow fluid to travel from one location on the mesh surface to another location over an opening into the supporting body, and does not provide "straight-through" openings, thus forcing the fluid to make multiple turns to pass through the mesh, thereby dissipating the fluid's energy and increases the mesh's erosion resistance. When particulate matter accumulates on the mesh's surface, the resulting particle cake remains porous, heightening the filter's resistance to plugging.

Abstract: A sand-filtering screen-making technique and screen are disclosed, which involves an initial assembly of the sand-filtering screen over an underlying coarse screen. The sand-filtering screen has a mechanical, longitudinal overlap-type joint. End caps are fitted over the filtering screen which has already been preassembled to the underlying coarse screen. The assembly is then mechanically forced through a die to compress the end caps onto the assembled filtering screen and underlying coarse screen. That subassembly is then assembled onto a base pipe and secured. An outer shroud can then be secured to the underlying base pipe, overlaying the filtering screen. The ends of the subassembly comprising the filtering screen and the underlying coarse screen are sealed against the support pipe by a packing gland arrangement at both ends.

Abstract: A sand filter for use in a well is provided employing a length of perforated tubing. A tubular wedge wire screen is telescopically positioned on the tubing covering the perforations. A plurality of tubular corrugated filter elements are then positioned on the wedge wire screen in end-to-end relationship. Each of the filter elements is formed of diffusion bonded multiple layers of wire mesh and each of the filter elements is corrugated to provide an external surface having an area at least three times the area of the cylindrical external surface of the tubular wedge wire screen that is encompassed by each filter element. The corrugated filter elements are secured on the wedge wire screen and welded in abutted end-to-end position.

Abstract: The present invention provides a well filter assembly for incorporation in a production system which will initially allow passage of particles which will only minimally damage the interior of the production system. After a period of time, the filter assembly will preclude passage of all damaging particles while allowing passage of those particles which will not deteriorate or obstruct the production system. Additionally, the well screen assembly is designed to mechanically break down the filter cake which was formed during drilling of the well in order to preclude plugging of the filter. Further, the filter of the prepacked well screen assembly is of sufficient strength so as to maintain its filtering capacity even after damage due to deformation. Finally, a method is provided for utilizing the well filter assembly in a production system.

Abstract: A well liner having a selective isolation screen with a limited or less restrictive seal. The well liner includes an elongate base pipe having openings therethrough; surrounded by circumferentially spaced, longitudinal extending spacer bars for forming an inner annulus; one or more annular cylindrical sleeves secured to the exterior of the base pipe; and a continuous wire wrapping surround the spacer bars except at interrupted areas where the isolated permeable seal sections are placed. These seal sections are located at predetermined vertical locations corresponding to specific well requirements of varying lengths and production formations within the wellbore. The continuous wire wrapping and spacer bars are inverted within the permeable seal sections so that the wire wrapping substantially fills the inner annulus and a multitude of spacer bars spaced approximately equal to or slightly larger than the spaces between the wire wrapping form the outer most surface of the seal sections.

Abstract: A method of removing iron from ground water located in a water well and of preventing production of hydrogen sulphide in such water including positioning a bubbling device in the well below the waterline. This device, which is connected to a source of pressurized air, is operated to produce a continuous flow of air bubbles in the water to render dissolved iron in the water insoluble so that the latter precipitates out and the well water aerobic. The insoluble iron can then be gathered from the well periodically. In one version, an iron collecting device in the form of a bag is placed around the bubbling device. The bag is removable from the well in order to remove and dispose of collected insoluble iron. Calcium carbonate can be used to adjust the pH level to pH 7. When the bubbling device is introduced into water containing sulphur, the air stream of bubbles has a double action and prevents hydrogen sulphide production.

Abstract: A prepack sand screen assembly has resistance welded inner and outer screens concentrically mounted in radially spaced relation onto a perforated mandrel, thereby defining an annulus in which prepack gravel is loaded. The longitudinal spacing distance between adjacent turns of the inner and outer screens selectively exclude sand fines of a predetermined minimum size. The outer screen wire is substantially greater in size as compared to the corresponding dimension of the inner retention screen wire. The inner retention screen is radially spaced with respect to the perforated mandrel, thereby defining a bypass flow annulus. The effective inlet flow area through the inner retention screen is more than twice the effective inlet flow area through the outer screen. Accordingly, localized deposits of sand fines on the inner screen are effectively bypassed by the remaining flow passages formed across the inner retention screen.

Abstract: A method and apparatus are provided for use on a subterranean well gravel packing conduit. The apparatus incorporates a cylindrically shaped inner tubular member having an interior wall and an exterior wall. A fluid flow passageway is defined within the interior wall of the tubular member and fluid flow passage means extends from the interior of the tubular member through the exterior wall and communicates with the fluid flow passageway. In a preferred embodiment, an outer fluid-porous means, or particulate restricting means is carried around the exterior wall of the tubular member having its interior facing the tubular member.

Abstract: Sand is filtered from an oil flow from a sand-containing oil producing formation or interval of an oil well by passing the oil flow with entrained sand through a filter assembly containing filtering media in the form of a body of juxtaposed composite particles. Each composite particle has an iron-containing core surrounded by a continuous chromium cladding, the composite particles having a size to permit passage of the oil flow through the body of the composite particles while substantially preventing flow of sand therethrough.

Abstract: Improved well screen has its open area defined by a helically wrapped strip of wire mesh which is supported by a rigid cage-like structure of welded steel longitudinal support rods and helical wrap wires. The design is cost competitive with the simple, and rather fragile, screens made by wrapping a mesh about a perforated pipe while offering the mechanical strength characteristics of wire-wrapped welded screens and a substantially larger open area for flow. The wire mesh strip is helically wound with a gap and at least one wrap wire is helically wound in the gap so that a small portion of its width can be firmly adhered to the rods while at least another portion of its width overlies an adjacent side edge of the mesh strip.