2258 results about "Low permeability" patented technology

A composite magnetic core formed of a high permeability material and a lower permeability, high saturation flux density material prevents core saturation without an air gap and reduces eddy current losses and loss of inductance. The composite core is configured such that the low permeability, high saturation material is located where the flux accumulates from the high permeability sections. The presence of magnetic material having a relatively high permeability keeps the flux confined within the core thereby preventing fringing flux from spilling out into the winding arrangement. This composite core configuration balances the requirements of preventing core saturation and minimizing eddy current losses without increasing either the height or width of the core or the number of windings.

A first flux-loop inductive coupler element electrically couples with a second flux-loop inductive coupler element. The first flux-loop inductive coupler element comprises a first ring-like core having high magnetic permeability and a conical-section annular first face transverse to the plane of the first core. The first face has a first annular groove separating a first conical-section larger-diameter face and a first conical-section smaller-diameter face. A first coil is wound within the annular groove. The first and second cores form a low-reluctance closed magnetic path around the first coil and a second coil of the second flux-loop inductive coupler element.

A first current-loop inductive coupler element electrically couples with a second current-loop inductive coupler element. The first current-loop inductive coupler element has a first high-conductivity, low-permeability shaped belt of a first end of a first pipe joint, a first ring-like core located at the first end, and a first electrically conductive coil wound about the first ring-like core. The first high-conductivity, low-permeability shaped belt partially encloses the first coil. It is shaped to cooperate with the second high-conductivity, low-permeability shaped belt of an adjacent second pipe joint having a second electrically conductive coil and a second high-conductivity, low-permeability shaped belt to create a closed toroidal electrical conducting path. The closed toroidal electrical conducting path encloses the first coil and the second coil when the first and second pipe joints are mated.

An absorbent article comprising a central absorbent member and a lateral wicking barrier for inhibition of wicking from the central regions of the article to an outlying outer absorbent member. The wicking barrier has a vertical component for prevention of radial wicking in the plane of the article and thus promotes center filling of the article with fluid and reduces the likelihood of leaks from the sides of the article. The wicking barrier can also have a horizontal component to prevent leakage, redirect fluid flow, and improve fit and performance of the article. In one embodiment, the central absorbent member is a concentric absorbent structure having alternating rings of barrier material and absorbent material, including a spiral wound composite formed from a layer of barrier material wound with a layer of absorbent material and then sliced to provide a thin absorbent layer having high permeability in the thickness direction but low permeability in the plane due to the barrier material.

PCT No. PCT/JP97/01514 Sec. 371 Date Jan. 28, 1998 Sec. 102(e) Date Jan. 28, 1998 PCT Filed May 2, 1997 PCT Pub. No. WO97/45489 PCT Pub. Date Dec. 4, 1997A pneumatic tire having an air permeation preventive layer comprising a low permeability thermoplastic elastomer composition comprising a thermoplastic elastomer having a thermoplastic resin composition as a continuous phase and a rubber composition as a dispersed phase, in which a barrier resin composition is contained, which low permeability thermoplastic elastomer composition has a phase structure in which the barrier resin composition is dispersed in the form of a flat state in the thermoplastic elastomer, is abundant in flexibility, is superior in gas permeation preventive property, and enables the tire to be reduced in weight.

A method for well construction and completion is disclosed. First, a productive section of a well is drilled in the presence of a fluid system that controls fluid losses, is substantially non-damaging to the formation and includes particles in a particle size distribution sufficient to form a low permeability filter cake on a formation face and to allow the majority of the filter cake particles to flow back into the borehole after well completion. after drilling, a casing includes at least one and preferably a plurality of extendable permeable elements or member is run in the well so that the elements are positioned and aligned with sites in the producing formation and once extended form production conduits between the formation and an interior of the casing. A completed borehole is also disclosed including a casing having production conduits formed from the extendable members or elements.

The use of low permeability magnetic material (NSME) with the disclosed design strategies form a two-stage isolated output converter system with the distinct advantages of superior density, efficiency, thermal operating bandwidth, service life, transient survival, and form factor flexibility over the prior art. These improvements are realized by, optimized application of NSME, efficient rectifying flyback management techniques, inclusion of switching buffers that substantially reduce switching losses. The instant invention provides power factor correction, output regulation, inrush limiting, over voltage, over current, over temperature, and transient protection, multi-converter load sharing, hot swapability, and fault signals.

The disclosed system is designed, specified, and certified to function from −40 deg. C. to +65 deg. C. from a 180 vac to 264 vac 50/60 Hz input line and supports 1000 watts of output or 600 watts from 90 vac to 120 vac 50/60 Hz line input at greater then 0.95 power factor and features a packaged power density of 14 watts per cu. in. at high line.

A method for forecasting performance for and characterizing the properties of a multilayer low permeability gas reservoir. The method includes a coupled well/reservoir predictive model that accounts for pressure drop between layers, allowing accurate, rigorous, and rapid forecasting of reservoir performance. The method provides estimates of individual layer properties such as in-situ permeability, skin factor, fracture half-length, fracture conductivity, drainage area, etc. by simultaneously history matching production data and production log data using the coupled well/reservoir predictive model.

Embodiments of hydraulic fracturing methods disclosed herein use fine mesh proppant. In one embodiment the method is used to fracture a low permeability formation. In one embodiment the method uses flocculation to improve conductivity of a fracture. In one embodiment fluid flow through the fine mesh proppant in the fracture creates a network of connected channels to improve the fracture conductivity.

The invention relates to a coiled tubing supercritical CO2 jet fracturing method. The method is used for performing jet fracturing on oil well reservoirs by taking supercritical CO2 as fracturing fluid. By the method, a supercritical CO2 fluid is used as the fracturing fluid to perform the jet fracturing; a supercritical CO2 sand jet perforating hole can reduce system pressure; the pressure needed by fissure extension can be further reduced by the characteristics of low viscosity and high dispersion performance of the supercritical CO2 fluid; most importantly, the supercritical CO2 jet fracturing does not pollute the reservoirs, but the supercritical CO2 can further improve the oil and gas recovery ratio after entering the reservoirs; the return discharge is not needed after the fracturing is completed; when the stage-by-stage jet fracturing is performed by using the coiled tubing, a tube pillar can be lifted or put down without mineshaft pressure relieving, the operation process is reduced and the operation cost is reduced, so that the method is extremely suitable for fracturing modification of unconventional oil-gas reservoirs such as thick oil reservoirs, low permeability and super-low permeability oil-gas reservoirs, shale gas reservoirs, coal bed methane reservoirs and the like of which the effects are low by using the conventional water-based fracturing fluid.

Corrosion resistant non-polar polymer coatings and methods for applying the coatings to substrates are described, wherein a source of non-polar polymer powder is deposited as a coating onto the surface of a substrate by high temperature thermal spray. The non-polar character of the powder and any additives thereto is substantially preserved during the high temperature thermal spray process by the use, at one or more locations along the thermal spray route, of at least one non-oxidizing shielding gas, at least one reducing gas, or a combination of the two types of gases to displace or react with ambient oxygen. High velocity impact force (HVIF) spraying techniques are preferred. Similarly processes and materials for low permeability and non-corrosive HVIF coatings for steel fuel tanks are disclosed.

Coated inflatable fabrics, more particularly airbags to which very low add-on amounts of coating have been applied, are provided which exhibit extremely low air permeability. The inventive inflatable fabrics are primarily for use in automotive restraint cushions that require low permeability characteristics (such as side curtain airbags). Traditionally, heavy, and thus expensive, coatings of compounds such as neoprene, silicones and the like, have been utilized to provide such required low permeability. The inventive fabric utilizes an inexpensive, very thin coating to provide such necessarily low permeability levels. Thus, the inventive coated inflatable airbag comprises a film laminated on at least a portion of the target fabric surface wherein the film possesses a tensile strength of at least 2,000 and an elongation at break of at least 180%. The film provides a low permeability airbag cushion exhibiting a leak-down time of at least 5 seconds wherein the film is present on the surface in an amount of at most 3.0 ounces per square yard of the fabric.

The invention discloses a method for extracting gas from high gas low permeability coal seam by punching, slotting, pressure releasing and permeability increasing, comprising the following steps: whena drill is drilled into a predetermined position of the coal seam, coal bodies at both sides of a drill hole are cut in the drill hole by high pressure water jet with a certain pressure and flow; a flat slot is formed at both sides of the drill hole; the cut coal bodies is led out the hole by the high pressure water jet. The exposed area of the coal body at the slotted part in the drill hole aregreatly increased, namely that an extremely thin protective layer is exploited with local scope of the flat slot, which enlarges effective influential range of pressure releasing, permeability increasing and gas discharging of the coal bodies in the drill hole, thus the air permeability of the coal bodies is increased about 200-300 times, the average amount of single-hole gas extraction reaches 0.3m<3>/min, the concentration of the gas extraction is 30-60%, gas drainage rate of working face of coal extraction is more than 50%, the number of drill holes for gas drainage is reduced by 10-20% after slotting, pressure releasing and permeability increasing. The method realizes the safety, high efficiency and uniform extraction of the gas from the high gas low permeability outburst coal seam, and changes high gas coal seam with outburst danger into low gas coal seam without outburst danger.

The present invention is an improved endovascular device particularly useful for use in transjugular intrahepatic portosystemic shunt (TIPS) procedures. The device employs a two-part stent-graft construction that provides a low permeability membrane to line the shunt and an uncovered stent portion designed to reside in the portal vein. The device provides numerous benefits over previous stents and stent-grafts used in TIPS procedures, including being more compact to deliver, being easier to accurately deploy, a controlled compacted surface with tucked apices, an improved stent winding pattern, and being more flexible in delivery and use.

A perpendicular magnetic recording disk having a single domain exchange-coupled laminated soft magnetic underlayer (SUL) is disclosed. The SUL is a combination synthetic anti-parallel coupled SUL structure, which has the product (Mst) of saturation magnetization and film thickness of the middle ferromagnetic layer less than the sum of the Mst of the bottom and top ferromagnetic layers. Subjected to a post radial field reset process, this SUL provides single domain state. Moreover, both robustness of stray fields and low permeability are obtained while keeping excellent corrosion resistance and cost effective manufacturability.

The invention relates to a method for integrated comprehensive management of gas in a low-permeability single coal bed, which can effectively solve the problem of comprehensive management and utilization of the gas. A technical scheme of the method comprises the following steps of: firstly, drilling holes, wherein a high-torque drilling machine and a rifle or a trihedral drill stem are used for solving the phenomenon of clamping the drill stem caused by collapsing and jetting of the holes in the hole drilling process; and then, performing hydraulic fracturing permeability improvement on the coal body, drilling holes for pre-split blasting, performing gas drainage, and recycling the drained gas, thereby implementing the integrated management of the gas. With the method provided by the invention, the permeability of the coal body is improved, a pre-draining rate of the gas is improved, and the drained gas is recycled, so that the drilled holes are radically prevented from being blocked in the construction process, the problem of difficulties in draining the gas in the low-permeability coal bed with a drilling tool having insufficient capability in the drilling construction is solved, consequently, outburst risk of the coal and the gas is reduced, outburst accidents of the coal and the gas are reduced and even avoided, and mine production safety and lives of coal mine workers are ensured, so that the method brings great economic and social benefits.

A package or container for holding two or more types or brands of smoking articles, such as cigarettes, having a generally rectangular shape with two openings on opposite sides of the container and a method of making the same is disclosed. The container has two lids, a body, and a separation member that divides the container into two or more compartments, each filled with smoking articles. The lids are made of metal and are hinged to the body on opposite ends of the container using strap hinges made of a paper or foil laminate, and contain printed information such as text and logos. The separation member includes raised portions to hold the smoking articles securely within the compartments and each compartment is sealed with a layer of film that may be pulled up and off of the container compartment using a tab attached to the sealing layer. The freshness and diffusion of aromas from the different types or brands of smoking articles is prevented from migrating between the separate compartments by use of low permeability materials including various plastics and metals.

A low permeability coupling device for coupling a first endpiece (3) extending a tube (2) with a second endpiece (10) carried by the wall (1) of a member to which the tube (2) is connected, in which the second endpiece (10) has two substantially coaxial walls (11, 12) defining between them a blind annular housing (13) for receiving the first endpiece (3), and a sealing element (15) extending between the inside face (11a) of the outer wall (11) of the second endpiece and the outside surface (8) of the first endpiece when it is in place in the above-mentioned housing (13).

The invention relates to the technical field of an oil-based drilling fluid for petroleum drilling, in particular to an environmental-friendly type oil-based drilling fluid and a preparation method therefore. The environmental-friendly type oil-based drilling fluid is prepared from the following raw materials: base liquid white oil, calcium chloride water solution, an emulsifying agent, a wetting agent, organic oil for drilling fluid, a composite plugging agent, a shear strength improving agent, a basicity regulating agent and a fluid loss additive; and a weighting agent is added into a mixture of the raw materials. The oil-based drilling fluid has the following advantages of: good plugging property, high shear viscosity and strong rock carrying capability; the EC 50 (median effect concentration) of the drilling fluid is larger than 3*104mg/L; the drilling fluid has good environmental safety; the return permeability of the drilling fluid can reach 90%-98%; the drilling fluid has little damage to reservoirs; the preparation process of the drilling fluid is simple; the drilling fluid is mainly applied to a special construction technology such as underbalance, horizontal wells and the like, water sensitivity reservoirs and low-pressure low permeability gas wells.

A process for producing paper webs having a pattern formed into the web is disclosed. The pattern is formed during formation of the web and is made by varying the basis weight of the web. The paper web is produced by depositing an aqueous suspension of fibers between two forming surfaces. One or both of the forming surfaces include lower permeability areas that create lower basis weight areas in the web. The lower permeability areas are contained in the forming surface according to a particular pattern. For instance, the lower permeability areas can be formed into a drainage roll sleeve contained on a drainage roll which contacts a forming surface. The drainage roll can be a forming roll or a breast roll.

An indirect evaporative cooler includes a number of heat transfer plates. Each plate has a wet side and a dry side, and the dry sides of adjacent plates face each other. The plate dry sides have low permeability to an evaporative liquid. Input air flows over the dry sides from an input end to an output end. Part of the input air becomes product air and exits at the output end. The rest of the input air passes through perforations in the plates to the other side of the plates to become working air. The other side of each plate is a wet side, which is wet by an evaporative liquid. Working gas flows over the wet side, evaporating the evaporative liquid and cooling the evaporative liquid, the plate, and finally the product gas by heat transfer. The perforations are formed both toward the input end of the plate and toward the output end of the plate. Part of the wet side of the plate, toward the output end of the plate, has a plurality of barriers placed to cause the working gas at that end of the plate to flow in a direction generally counter to the input air.