Magnetorheological fluids may regulate fluid flow downhole by forming a fluid seal using a bridge plug apparatus. Bridge plug apparatuses employing a magnetorheological fluid may be deployed in a wellbore in a retrievable configuration or in a substantially permanent configuration. Retrievable bridge plug apparatuses may comprise spaced apart magnets having a gap defined therebetween, and a reservoir of magnetorheological fluid housed within the gap. The magnets move laterally with respect to one another to expand or contract the gap and to displace the reservoir of magnetorheological fluid radially with respect to the magnets. Other bridge plug apparatuses may comprise a flow path extending between a reservoir of magnetorheological fluid and the exterior of a housing, where at least a portion of the flow path is located within a gap defined between spaced apart magnets.

Magnetorheological fluids may regulate fluid flow downhole by forming a fluid seal using a bridge plug apparatus. Bridge plug apparatuses employing a magnetorheological fluid may be deployed in a wellbore in a retrievable configuration or in a substantially permanent configuration. Retrievable bridge plug apparatuses may comprise spaced apart magnets having a gap defined therebetween, and a reservoir of magnetorheological fluid housed within the gap. The magnets move laterally with respect to one another to expand or contract the gap and to displace the reservoir of magnetorheological fluid radially with respect to the magnets. Other bridge plug apparatuses may comprise a flow path extending between a reservoir of magnetorheological fluid and the exterior of a housing, where at least a portion of the flow path is located within a gap defined between spaced apart magnets.

A method of controlling fluid flow between two tubulars includes disposing a sealing member in an annular area between two tubulars, wherein the two tubulars partially overlap; moving the sealing member to a lower position where it is not in contact with one of the tubulars, thereby allowing fluid flow through the annular area; and moving the sealing member to an upper position where it is in contact with both of the tubulars, thereby preventing fluid flow through the annular area.

A method of controlling fluid flow between two tubulars includes disposing a sealing member in an annular area between two tubulars, wherein the two tubulars partially overlap; moving the sealing member to a lower position where it is not in contact with one of the tubulars, thereby allowing fluid flow through the annular area; and moving the sealing member to an upper position where it is in contact with both of the tubulars, thereby preventing fluid flow through the annular area.

Activation modules for selectively sealing entrances to inner barrels of coring tools may include an activator body sized and configured to obstruct the entrance to the inner barrel when the activation module is in a first state and to release the entrance to the inner barrel when the activation module is in a second state. A sealing element may be located at a periphery of the activator body, and may be configured to form a seal between at least a portion of an interior of the inner barrel and at least a portion of an exterior of the inner barrel when the activation module is in the first state and to disengage the seal when the activation module is in the second state.

The invention is directed to a device and to a method for utilizing groundwater, comprising two wells whose well water levels are at different elevations, a connecting line between the well water reservoirs of the two wells, a hydraulic motor, or a pump that is operable as a generator, inside the connecting line, and an electrical generator that is mechanically coupled to the hydraulic motor or to the pump that is operable as a generator.

The invention is directed to a device and to a method for utilizing groundwater, comprising two wells whose well water levels are at different elevations, a connecting line between the well water reservoirs of the two wells, a hydraulic motor, or a pump that is operable as a generator, inside the connecting line, and an electrical generator that is mechanically coupled to the hydraulic motor or to the pump that is operable as a generator.

A slurry outlet system including a top sub, a closure sleeve movable relative to the top sub between a closed position and an open position, a seal mounted on one or the other of the top sub or the closure sleeve, a protector sleeve disposed to cover the seal until displaced by one or the other of the top sub or the closure sleeve that does not include the seal during movement to the closed position. A method for pressure sealingly closing a slurry outlet system including bringing a closure sleeve into proximity with a top sub of the slurry outlet system, displacing a protector sleeve, with the closure sleeve, off a seal disposed about the closure sleeve and simultaneously making sealing contact between the top sub and the seal.

A downhole sealing apparatus having a sealing assembly with one or more seal elements configured to engage a bore wall or bore-lining tubular wall to seal an annulus between the apparatus and the wall or tubular wall. A bypass arrangement is configured to provide selective bypass of the sealing assembly and the sealing apparatus is reconfigurable between a first configuration permitting bypass of the sealing assembly and a second configuration in which the bypass arrangement prevents or restricts bypass of the sealing assembly. A downhole method provides the downhole sealing apparatus within a bore hole, with the downhole sealing apparatus reconfigured from the first configuration in which the bypass arrangement permits bypass of the sealing assembly to a second configuration in which the bypass arrangement prevents or restricts bypass of the sealing assembly.

Bottom hole assemblies for deploying sheets of material in a wellbore include: a body configured for attachment to a drill pipe; a spool ring attached to the body; a spring ring; and rolls of fabric.