A fail-safe method to cement a section of casing string to a formation is provided. The method includes providing the casing string in a wellbore, the casing string comprising a stage tool, a packer, and a sensor. The packer is located vertically below the stage tool and vertically above the sensor on the casing string. The method further includes pumping cement down the casing string and up an annulus to an expected height, the expected height being a vertical distance above the sensor, and detecting a presence or absence of cement with the sensor. If the sensor detects the presence of cement, the stage tool is kept closed and the packer is kept deflated. If the sensor detects the absence of cement, the stage tool is opened and the packer is inflated.

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 technique facilitates simplified cementing operations in a borehole with fewer trips downhole. The technique utilizes a cementing system having a stage cementing collar in combination with a cup tool. According to an embodiment, the stage cementing collar may comprise a collar body, a no-go connected to the collar body, and a port closure sleeve which serves as a valve positioned to close/open flow ports extending laterally through the collar body. The cup tool may be conveyed downhole on, for example, jointed pipe or coiled tubing, for engagement with the port closure sleeve. The cup tool is used to shift the port closure sleeve between operational positions, e.g. from a port open to a port closed position.

A downhole tool for use in a well comprising a mandrel and an outer sleeve slidably disposed about the mandrel. An inner sleeve is slidably disposed in the mandrel. A drive pin comprising a drive pin bushing connected to the outer sleeve and a shear pin connected to the inner sleeve connects the inner sleeve to the outer sleeve.

A stage cementing tool has a mandrel defining a central flow passage and a plurality of fully open cement flow ports. A packer disposed about the mandrel is movable from an unset to a set position. An opening sleeve is movable in the mandrel from a closed position to an open position in which the flow ports are exposed to allow flow therethrough. The opening sleeve is operable to move the setting sleeve to set the packer against the wellbore as it moves in the mandrel from the closed to the open position.

A stage cementing tool has a mandrel defining a central flow passage and a plurality of cementing passages in a wall thereof. A packer is disposed about the mandrel. A closing sleeve is detachably connected to and movable relative to the mandrel. An opening sleeve defining a plurality of fully open cement flow ports therethrough is telescopically movable relative to the closing sleeve and movable relative to the mandrel. The opening sleeve is movable to move the packer to the set position, and thereafter movable to open a cement flow path between the central flow passage and an annulus defined by the stage cementing tool and the wellbore.

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.

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 wellbore tool includes a housing including a wall having an outer surface and an inner surface defining a passage. The housing has an outlet extending through the wall. A valve sleeve is axially slidably arranged in the passage. The valve sleeve includes a wall portion including a first end, a second end, an outer surface portion, an inner surface portion, an outlet portion that selectively aligns with the outlet in the housing. A locking mechanism is provided on the valve sleeve. A valve seat is axially slidably arranged at the first end of the valve sleeve. The valve seat being selectively rotationally locked to the valve sleeve by the locking mechanism.

A catcher for use in a wellbore includes a housing and an insert disposed within the housing. A method of using the catcher includes disintegrating at least a portion of the insert while the insert is held rotationally stationary with respect to the housing by a taper connection between the insert and the housing.