A method of cementing a casing in a wellbore includes lowering the casing in the wellbore. The casing includes multiple pipes each of progressively smaller diameters, and a transition point where a first pipe overlaps a second pipe. The method also includes flowing cement into the casing and deploying, by fluidic pressure, a wiper plug assembly in the casing upstream of the cement to push downhole the cement with the wiper plug assembly. The wiper plug assembly includes a hollow wiper plug and a solid wiper plug releasably coupled to the hollow wiper plug. The deploying includes applying fluidic pressure until the hollow wiper plug reaches and is retained at the transition point and the solid wiper plug is released from the hollow wiper plug to flow downhole in the casing to a downhole end of the casing and push the cement out of the casing.

A method of cementing a casing in a wellbore includes lowering the casing in the wellbore. The casing includes multiple pipes each of progressively smaller diameters, and a transition point where a first pipe overlaps a second pipe. The method also includes flowing cement into the casing and deploying, by fluidic pressure, a wiper plug assembly in the casing upstream of the cement to push downhole the cement with the wiper plug assembly. The wiper plug assembly includes a hollow wiper plug and a solid wiper plug releasably coupled to the hollow wiper plug. The deploying includes applying fluidic pressure until the hollow wiper plug reaches and is retained at the transition point and the solid wiper plug is released from the hollow wiper plug to flow downhole in the casing to a downhole end of the casing and push the cement out of the casing.

A stage tool comprises a body with a tubular wall, defining an outer surface and an inner surface. Fluid ports, such as cement circulation ports, extend through the tubular wall. The stage tool further comprises a primary closing sleeve. The primary closing sleeve may be movable along the outer surface of the tubular wall for closing the ports when the treatment of the wellbore stage ends. A secondary closing sleeve may be movable along the inner surface of the tubular wall for closing the port in case of failure of the primary closing sleeve or for redundancy. The primary closing sleeve may be actuated by an internal member joined to the primary closing sleeve by a crosslink and movable on the inner surface. The internal member and the secondary closing sleeve may move along different surfaces on the internal wall to avoid interference.

A hydraulic set packer system includes an outer sleeve and a mandrel extending through the outer sleeve. The mandrel has a setting port extending through a radial wall of the mandrel, and the setting port is configured to provide fluid communication from a central bore of the mandrel to a setting chamber formed between the outer sleeve and the mandrel. The system also includes a piston configured to move axially along the mandrel in response to a setting pressure in the setting chamber. The piston is configured to drive at least one radially actuatable component to actuate in a radial direction to engage a wellbore wall. Further, the system includes a pressure isolation assembly disposed in the setting chamber. The pressure isolation assembly is configured to move axially with respect to the mandrel from a first position to a second position to seal the setting port.

A hydraulic set packer system includes an outer sleeve and a mandrel extending through the outer sleeve. The mandrel has a setting port extending through a radial wall of the mandrel, and the setting port is configured to provide fluid communication from a central bore of the mandrel to a setting chamber formed between the outer sleeve and the mandrel. The system also includes a piston configured to move axially along the mandrel in response to a setting pressure in the setting chamber. The piston is configured to drive at least one radially actuatable component to actuate in a radial direction to engage a wellbore wall. Further, the system includes a pressure isolation assembly disposed in the setting chamber. The pressure isolation assembly is configured to move axially with respect to the mandrel from a first position to a second position to seal the setting port.

A packer for use in a wellbore includes a packer mandrel. First and second pistons are slidably disposed about the packer mandrel defining first and second chambers therewith. A first activation assembly initially prevents movement of the first piston. A second activation assembly initially prevents movement of the second piston. A seal assembly is disposed about the packer mandrel between the first and second pistons such that actuation of the first activation assembly allows a force generated by a pressure difference between the wellbore and the first chamber to shift the first piston in a first direction toward the seal assembly to radially expand the seal assembly and actuation of the second activation assembly allows a force generated by a pressure difference between the wellbore and the second chamber to shift the second piston in a second direction toward the seal assembly to radially expand the seal assembly.

A packer for use in a wellbore includes a packer mandrel. First and second pistons are slidably disposed about the packer mandrel defining first and second chambers therewith. A first activation assembly initially prevents movement of the first piston. A second activation assembly initially prevents movement of the second piston. A seal assembly is disposed about the packer mandrel between the first and second pistons such that actuation of the first activation assembly allows a force generated by a pressure difference between the wellbore and the first chamber to shift the first piston in a first direction toward the seal assembly to radially expand the seal assembly and actuation of the second activation assembly allows a force generated by a pressure difference between the wellbore and the second chamber to shift the second piston in a second direction toward the seal assembly to radially expand the seal assembly.

The present invention relates to a downhole device for being moved downwards in a well by fluid to assist stimulation of a production zone of the well, the well comprising a well tubular structure having a first opening and a first movable sleeve arranged opposite the first opening, and the well tubular structure having an inner diameter, the downhole device having an axial extension, and comprising: a first part comprising two projection elements having a profile matching grooves in the sleeve, and a second part comprising: a body, two anchor elements projectable from the body for anchoring the second part in the well tubular structure, and a sealing element configured to seal against the well tubular structure, the downhole device further comprising: a displacement mechanism comprising a piston movable within a piston cylinder to displace, in the axial extension, the first part in relation to the second part when anchored in the well tubular structure to operate the sleeve. The invention also relates to a downhole system for stimulating a formation surrounding a well tubular structure of a well. Finally, the present invention relates to a stimulation method for stimulating a formation by means of a downhole system according to the invention.

The present invention relates to a downhole device for being moved downwards in a well by fluid to assist stimulation of a production zone of the well, the well comprising a well tubular structure having a first opening and a first movable sleeve arranged opposite the first opening, and the well tubular structure having an inner diameter, the downhole device having an axial extension, and comprising: a first part comprising two projection elements having a profile matching grooves in the sleeve, and a second part comprising: a body, two anchor elements projectable from the body for anchoring the second part in the well tubular structure, and a sealing element configured to seal against the well tubular structure, the downhole device further comprising: a displacement mechanism comprising a piston movable within a piston cylinder to displace, in the axial extension, the first part in relation to the second part when anchored in the well tubular structure to operate the sleeve. The invention also relates to a downhole system for stimulating a formation surrounding a well tubular structure of a well. Finally, the present invention relates to a stimulation method for stimulating a formation by means of a downhole system according to the invention.

Embodiments described herein provide an expanding and collapsing apparatus and methods of use. The apparatus includes a plurality of elements assembled together to form a ring structure about a longitudinal axis. The ring structure is operable to be moved between an expanded condition and a collapsed condition by movement of the plurality of elements. At least one set of structural elements are operable to move between the expanded condition and the collapsed condition by movement of a first end in an axial direction, and by movement of a second end in a radial dimension. In certain embodiments, the plurality of elements includes at least one set of structural elements extending longitudinally on the apparatus and operable to slide with respect to one another. Applications of the embodiments described herein include oilfield devices, including anti-extrusion rings, plugs, packers, locks, patching tools, connection systems, and variable diameter tools run in a wellbore.