Abstract: Provided, in one aspect, is a cementing apparatus. The cementing apparatus, in one embodiment comprising a housing; a fixed member coupled with the housing, the fixed member having at least one fixed member fluid opening therein; and a moving member positioned downhole of the fixed member and movable between a circulating position and a cemented position, the moving member having at least one moving member fluid opening therein, the at least one moving member fluid opening linearly offset from the at least one fixed member fluid opening.

Abstract: Provided, in one aspect, is a cementing apparatus. The cementing apparatus, in one embodiment comprising a housing; a fixed member coupled with the housing, the fixed member having at least one fixed member fluid opening therein; and a moving member positioned downhole of the fixed member and movable between a circulating position and a cemented position, the moving member having at least one moving member fluid opening therein, the at least one moving member fluid opening linearly offset from the at least one fixed member fluid opening.

Abstract: A valve housing has a first flapper moveable from an open position in the housing in which two-way flow is allowed to a closed position in which only one-way flow is permitted. A first collet sleeve is moveable from a first position to a second position in the valve housing. The first collet sleeve in the first position retains the flapper valve in the open position. The collet sleeve is moveable from a first position to a second position which allows the flapper to move to a closed position.

Abstract: Provided, in one aspect, is a cementing apparatus. The cementing apparatus, in one embodiment comprising a housing; a fixed member coupled with the housing, the fixed member having at least one fixed member fluid opening therein; and a moving member positioned downhole of the fixed member and movable between a circulating position and a cemented position, the moving member having at least one moving member fluid opening therein, the at least one moving member fluid opening linearly offset from the at least one fixed member fluid opening.

Abstract: A valve housing has a first flapper moveable from an open position in the housing in which two-way flow is allowed to a closed position in which only one-way flow is permitted. A first collet sleeve is moveable from a first position to a second position in the valve housing. The first collet sleeve in the first position retains the flapper valve in the open position. The collet sleeve is moveable from a first position to a second position which allows the flapper to move to a closed position.

Abstract: A valve assembly has a housing defining a flow passage therethrough. A first flapper is disposed in the housing. A first sleeve retains the flapper in an open position. At least one lock ring holds the first sleeve in a first position. A tripping ball engages a plurality of disconnected bodies in the sleeve and a force is applied to move the first sleeve from the first to a second position.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier define a buoyancy chamber therebetween. A debris barrier positioned above the removable plug has a plurality of fragments interspersed in a stretchable material and includes a frangible disc.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug comprises a rigid annular ring with a flexible diaphragm covering the center opening defined by the annular ring.

Abstract: A downhole apparatus comprises a casing string with a fluid barrier connected in the casing string. A degradable plug is positioned in the casing string above the fluid barrier. The degradable plug and fluid barrier define upper and lower ends of a buoyancy chamber in the casing string. The degradable plug may be degraded to leave an open bore through the casing string after the casing string is lowered into a wellbore.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug comprises a rigid annular ring with a flexible diaphragm covering the center opening defined by the annular ring.

Abstract: A downhole apparatus has a casing string and a degradable plug positioned in the casing string to block flow therethrough. An upper membrane covers an upper end of the degradable plug. The upper membrane is made up of a plurality of separable membranes. A lower membrane covers a lower end of the degradable plug and is comprised of a plurality of separable membranes.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier define a buoyancy chamber therebetween. A debris barrier positioned above the removable plug has a plurality of fragments interspersed in a stretchable material and includes a frangible disc.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug comprises a rigid annular ring with a flexible diaphragm covering the center opening defined by the annular ring.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug includes a frangible disk. A stretchable connecting ring is connected to the frangible disk and to the casing.

Abstract: A downhole apparatus has a casing string and a degradable plug positioned in the casing string to block flow therethrough. An upper membrane covers an upper end of the degradable plug. The upper membrane is made up of a plurality of separable membranes. A lower membrane covers a lower end of the degradable plug and is comprised of a plurality of separable membranes.

Abstract: A downhole apparatus comprises a casing string with a removable plug therein to block flow therethrough. A flow barrier is positioned in the casing below the removable plug and the removable plug and the flow barrier defining a buoyancy chamber therebetween. A debris barrier positioned above the removable plug comprises a rigid annular ring with a flexible diaphragm covering the center opening defined by the annular ring.

Abstract: A downhole apparatus comprises a casing string with a fluid barrier connected in the casing string. A degradable plug is positioned in the casing string above the fluid barrier. The degradable plug and fluid barrier define upper and lower ends of a buoyancy chamber in the casing string. The degradable plug may be degraded to leave an open bore through the casing string after the casing string is lowered into a wellbore.

Abstract: A downhole tool. The downhole tool may include a tubular body and an inner sleeve that is slidable within the tubular body. The tubular body may include a port that allows fluid flow between a bore of the downhole tool and an area outside of the tubular body. The downhole tool may be sequentially positionable in a run-in position that blocks fluid flow through the port in the tubular body, then in an open position that allows fluid flow through the port in the tubular bod, and then in a closed position that blocks fluid flow through the port in the tubular body.