A single sleeve, multi-stage cementing tool for cementing in a wellbore can include a tool body, an outer mandrel, a flow port for providing fluid communication transversely from the inside of a tubing string into an annulus, and a port plug. The port plug is located within the flow port during first stage cementing such that the cement flows into the annulus from a bottom of the tubing string. The bottom of the tubing string can be closed after the first stage, and the port plug can be released from the flow port by increasing pressure within the tubing string. Second stage cementing can then be performed such that the cement flows into the annulus directly through the opened flow port. After all cement stages have been completed, a closing sleeve can be shifted to close the flow port.

The present invention relates to a ground double-hole combined water inrush prevention method for overlying strata movement monitoring and bed separation water drainage. By arranging a rock strata movement monitoring borehole and a bed separation water drainage borehole, interior movement information of an overlying stratum and bed separation generation timing fed back by strata movement monitoring performed inside are monitored; work on the bed separation water drainage borehole is guided by monitoring changes in arranged monitoring points; and through combination of the movement monitoring borehole and the bed separation water drainage borehole, the utilization rate of the bed separation water drainage borehole is effectively increased.

A method includes deploying a cementing assembly within a wellbore. The wellbore includes a loss circulation zone. The cementing assembly includes a work string and a liner assembly coupled to the work string. The liner assembly includes a polished bore receptacle, a liner hanger attached to a downhole end of the polished bore receptacle, a liner, and a cementing sub disposed between the liner hanger and the liner. The method includes anchoring the liner hanger on the casing of the wellbore, cementing an open hole annulus of the wellbore, and setting an annulus packer of the cementing sub on the. The method also includes cementing a casing annulus of the wellbore defined between an external surface of the cementing sub and a wall of wellbore.

An apparatus for flowing and mixing cement within a subterranean formation includes a housing, a flow control device, and baffles. The housing is configured to contain a cement additive. The housing includes a first end and a second end. The first end is configured to couple to a cement retainer. The flow control device is disposed at the second end of the housing. The baffles are disposed within the housing.

An openhole interval of a well may be sealed by deploying a liquified phase transformation material to the openhole interval and allowing it to harden. In at least one example, this may be performed in a single step of building and maintaining pressure. The pressure may rupture a membrane, to introduce a fluid into a chamber with a reactive material (e.g. powder) in a delivery chassis, whereupon the fluid may exothermically combine with the reactive material to liquify the solid phase transformation material. The same applied pressure may also deliver the liquified phase transformation material to a deployment chassis, which then distributes the liquified phase transformation material under pressure to the openhole interval of the well. Various delivery chassis, deployment chassis, and related compositions and methods are disclosed as well.

An apparatus for flowing and mixing cement within a subterranean formation includes a housing, a flow control device, and baffles. The housing is configured to contain a cement additive. The housing includes a first end and a second end. The first end is configured to couple to a cement retainer. The flow control device is disposed at the second end of the housing. The baffles are disposed within the housing.

A nozzle for use with a limited entry liner. A limited entry liner can house multiple nozzles and each nozzle can include a barrel and a central, dissolvable region. The dissolvable region is made of a material that has specific properties that allow the central region to withstand pressure and environment in a well up to a certain, known point at which time the central portion will dissolve and allow fluid to pass into the limited entry liner.

An assembly includes a cement retainer, a unidirectional flow valve, and an upper stinger. The cement retainer is adapted to be mounted in the casing string. The cement retainer has a retainer aperture extending longitudinally therethrough from a retainer top end to a retainer bottom end. The unidirectional flow valve is configured to selectively control flow of fluid through the retainer aperture and is housed within the cement retainer. The upper stinger is configured to be removably retained within the retainer aperture. The upper stinger has an upper stinger aperture extending longitudinally therethrough from an upper stinger top end to an upper stinger bottom end. The upper stinger comprises an opening that provides a fluid flow path from an interior of the casing string to the upper stinger aperture when the upper stinger is removed from the cement retainer.

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 stage cementing tool includes a housing configured to couple to a casing and having a central bore therethrough, a first plurality of ports arranged on a radial surface of the housing and configured to fluidly connect the central bore and an annulus of a wellbore, a second plurality of ports arranged on the radial surface of the housing uphole of the first plurality of ports and configured to fluidly connect the central bore and the annulus of the wellbore, an expandable element coupled to the housing between the first plurality of ports and the second plurality of ports, and a sleeve. The sleeve is moveable from a first position on the housing to a second position on the housing to fluidly disconnect the central bore and the annulus through the first plurality of ports and fluidly connect the central bore and the annulus through the second plurality of ports.