A downhole tool includes a support ring having an annular-shaped body, a thickness measured between an uphole side of the body and an opposite downhole side of the body, an extension distance measured between an inner diameter of the body and an outer diameter of the body, and one or more openings formed through the thickness of the body. A one-way valve is disposed in each opening formed through the support ring to limit flow through the support ring in a direction from the downhole side of the body to the uphole side of the body.

A rupture disc assembly and a float tool incorporating the rupture disc assembly is disclosed. The rupture disc assembly may include a rupture disc assembly comprising a rupture disc, an upper tubular portion and a lower tubular portion, and a securing mechanism for holding the rupture disc between the upper and lower tubular portions. A float tool for creating a buoyant chamber in a casing string may include the rupture disc assembly and a sealing device for sealing the lower end of the casing string, the buoyant, sealed chamber may be created there between. In operation, applied fluid pressure causes the rupture disc to move downward. The rupture disc may be shattered by contact with a surface on the lower tubular portion. Full casing internal diameter may be restored in the region where the rupture disc formerly sealed the casing.

A multi stage liner with cluster valves for completing and performing multiple fracture stimulations along a length of wellbore. Groups of cluster valves, with isolation between such groups of cluster valves, and a method of using same, are provided to achieve increased oil and gas flow to a wellbore in openhole or cased hole applications for oil and gas wells.

A stage tool assembly has a tubular body defining an interior bore with a port; an opening sleeve axially movable from a first position that restricts the port to a second position that exposes the port; a closing sleeve axially movable from a first position that exposes the port to a second position that restricts the port; and an isolation assembly downhole of the port that, at least when in an activated mode: permits tool passage in a downhole direction through the interior bore; and restricts flow through the interior bore.

A packoff device is disclosed for sealing an annulus within a wellbore, and for bypassing the sealed annulus. The packoff device may include a mandrel having a bore formed axially therethrough and first and second ports extending radially from the bore. A sealing element that extends radially-outwardly from the mandrel may be positioned axially between the first and second ports, and may create a seal within an annulus between the mandrel and a casing, to isolate a portion of the annulus above the sealing element from a portion below the sealing element. A sleeve within the bore may, with the mandrel, form a channel providing fluid communication between the first and second ports. The sleeve may be movable between open and closed states. The first and second ports may be unobstructed by the sleeve in the open state, one or more may be obstructed in the closed state.

A cementing tool for use in well drilling operations includes a body forming an inner bore, the body having circulation ports allowing flow from the inner bore to an exterior of the body; an opening sleeve mounted within the body to release from a first opening sleeve position to open the circulation ports when in a second position; an opening seat attached to the opening sleeve; an opening seat collet retainer engaged with the opening seat; a closing sleeve mounted within the body above the opening sleeve and to release from a first closing sleeve position to close the circulation ports; a closing seat attached to the closing sleeve; the closing seat is to apply pressure to the opening seat collet retainer; and the opening seat collet retainer is to release from the opening seat once a predetermined amount of pressure is applied from the closing seat.

A method of cementing a tubular string in a wellbore can include applying a predetermined pressure differential from a flow passage extending axially through the tubular string to an annulus surrounding the tubular string, thereby opening a rupture disk of a cementing stage tool connected in the tubular string, and then flowing a fluid through the flow passage and into the annulus via the rupture disk, thereby displacing an opening plug into engagement with an opening sleeve of the cementing stage tool. A cementing stage tool can include a longitudinal flow passage, an outer housing assembly, an opening sleeve that prevents fluid flow between the flow passage and a housing port in a run-in configuration, and a rupture disk that permits fluid flow between the flow passage and the housing port in response to a predetermined pressure differential applied from the flow passage to the housing port.

A method of cementing a tubular string in a wellbore can include applying a predetermined pressure differential from a flow passage extending axially through the tubular string to an annulus surrounding the tubular string, thereby opening a rupture disk of a cementing stage tool connected in the tubular string, and then flowing a fluid through the flow passage and into the annulus via the rupture disk, thereby displacing an opening plug into engagement with an opening sleeve of the cementing stage tool. A cementing stage tool can include a longitudinal flow passage, an outer housing assembly, an opening sleeve that prevents fluid flow between the flow passage and a housing port in a run-in configuration, and a rupture disk that permits fluid flow between the flow passage and the housing port in response to a predetermined pressure differential applied from the flow passage to the housing port.

A method of cementing a tubular string in a wellbore can include applying a predetermined pressure differential from a flow passage extending axially through the tubular string to an annulus surrounding the tubular string, thereby opening a rupture disk of a cementing stage tool connected in the tubular string, and then flowing a fluid through the flow passage and into the annulus via the rupture disk, thereby displacing an opening plug into engagement with an opening sleeve of the cementing stage tool. A cementing stage tool can include a longitudinal flow passage, an outer housing assembly, an opening sleeve that prevents fluid flow between the flow passage and a housing port in a run-in configuration, and a rupture disk that permits fluid flow between the flow passage and the housing port in response to a predetermined pressure differential applied from the flow passage to the housing port.

A downhole well tool includes a tubing including a circulation fluid pathway, a first packer, and a second packer positioned longitudinally apart from the first packer. The well tool includes a circulation sub connected to the tubing on a first longitudinal side of the second packer, the circulation sub including a first circulation port to fluidly couple the circulation fluid pathway to an annulus of the wellbore, and a plug seat positioned in the fluid circulation pathway. A second circulation port in the tubing is positioned longitudinally between the first packer and the second packer, and fluidly couples the circulation fluid pathway to the annulus of the wellbore between the first packer and the second packer. The second circulation port includes a frangible cover that plugs the second circulation port and ruptures in response to a burst pressure in the circulation fluid pathway.