A screen assembly, such as a downhole/sand screen assembly, comprising first and second screen portions or screens longitudinally coupled together, wherein there is provided a fluid flow path between the first and second screen portions or screen. Optionally, the first and second sleeves are coupled or connected by a centraliser or further sleeve or screen, and/or optionally by or via first and second support ring.

A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.

A well screen system includes upstream and downstream screen assemblies arranged along an axis. The assemblies each have first and second transport tubes. A first packing tube is connected to the first transport tube by first adapter and has an uppermost nozzle axially spaced from the first adapter by a first effective packing tube length. A second packing tube is connected to the second transport tube by a second adapter and has an uppermost nozzle axially spaced from the second adapter by a second effective packing tube length different than the first effective packing tube length. The downstream screen assembly second transport tube is connected to the upstream screen assembly first transport tube to alternate the effective packing tube lengths of packing tube uppermost nozzles along the screen system. Methods of making well screen systems and methods of gravel packing well screen systems are also disclosed.

A lower completion assembly made up of an upper sand screen assembly and a lower sand screen assembly. Each sand screen assembly includes a shunt system. Each shunt system includes a transport tube and a packing tube extending from a junction block. Each packing tube includes a plurality of nozzles spaced apart from the junction block and from each other. The shunt system of the upper sand screen assembly has a higher pressure rating than the shunt system of the lower sand screen assembly. The wall thickness of the transport tubes of the upper sand screen assembly shunt system is greater than the wall thickness of the transport tubes of the lower sand screen assembly shunt system.

A well screen for a borehole. The well screen may include an arcuate outer shroud, a mesh layer, and a drainage layer. The arcuate outer shroud may include perforations, a first longitudinal end, and a second longitudinal end. The first and second longitudinal ends may be spaced arcuately apart such that a gap is formed between the first and the second longitudinal ends of the outer shroud. The mesh layer may restrict flow of particulate materials of a predetermined size from passing therethrough and is positioned radially inward from the outer shroud. The mesh layer may include a first and a second longitudinal end that are radially aligned with the first and the second longitudinal ends of the outer shroud to continue the gap. The drainage layer may be positioned radially inward from to the mesh layer and may include at least one of perforations or louvers.

A device and method for collecting sample fluids from an underground source which includes sample wells terminating in a corrugated conduit and sieve. The sampling regions for each sample well is separated by a grout or expanding seal barrier. Negative pressure is optionally applied to extract fluids from the underground matrix for sampling. The device can also be used for remediating an environmental contaminant from soil or aquifers. Upon identification of at least one environmental contaminant, a remediation composition is injected into the soil or aquifer using the sampling wells of the device. The remediation fluids can be directed to specific locations by selectively utilizing one or more sampling wells to inject the remediation fluid.

A method of non-line-of-sight coating of a sand screen for use in wellbores during the production of hydrocarbon fluids from subterranean formations. The coating can have uniformly coated internal and external surfaces.

The present invention relates to a system for contaminant extraction in a borehole extending from a surface of the Earth through a water permeable layer and into an underlying production zone, the system comprising: an outer casing located within the borehole and extending through the water permeable layer; a production pipe located within the casing and extending towards the production zone; a filter assembly occupying at least part of an intermediate zone between the outer casing and the production pipe, wherein the filter assembly is configured to capture contaminants before they enter the water permeable layer and/or before they are released into the atmosphere, the filter assembly comprising: a lower solids filtering stage configured to filter solid contaminants; and an upper fluids filtering stage configured to filter fluid contaminants migrating from the production zone through the lower solids filtering stage; and sealing means for preventing the uncontrolled leakage of contaminants from the intermediate zone. Methods for contaminant extraction, a contaminant filtration system and solid and fluid filter modules are also disclosed.

An expandable liner and a method for running the same including a base pipe, wherein the base pipe is provided with a passage extending through an axial direction of the base pipe, a connection structure disposed at both ends of the base pipe, and screen openings on a wall of the base pipe; a porous expandable layer is fixedly attached to an exterior of the base pipe and made of a non-memory formed and compressible material. The expandable liner and the method, by adopting a non-memory porous expandable layer, realize a sand-control performance and a wellbore-supporting capability of a technology where memory materials are used in manufacturing, operating and running.

An adaptive fluid switch for regulating the production rate of a fluid. The adaptive fluid switch includes a fluid control valve having a fluid selector, a swirl chamber and a self-impinging valve element. When the fluid produced through the adaptive fluid switch has a viscosity greater than a first predetermined level, the fluid selector determines the fluid to be a selected fluid such that the fluid swirls in one direction in the swirl chamber and follows a low resistance flow path in the valve element. When the fluid has a viscosity less than a second predetermined level, the fluid selector determines the fluid to be a non-selected fluid such that the fluid swirls in the opposite direction in the swirl chamber and follows a high resistance flow path in the valve element, thereby regulating the production rate of the fluid responsive to changes in the viscosity of the fluid.