Embodiments of the disclosure provide an unfoldable device for controlling lost circulation in a target lost circulation zone in a borehole. The unfoldable device includes a sheet, a backbone, and a shell. The sheet has an unfolded state and a folded state. The backbone reinforces the sheet. The backbone includes a shape-memory material having an original state and a deformed state. The shell encapsulates the sheet in the folded state and the backbone in the deformed state. In some embodiments, the shell includes a degradable polymer that degrades in the borehole upon contact with a drilling fluid such that the sheet transitions to the unfolded state and the backbone transitions to the original state. The sheet in the unfolded state accumulates on a borehole wall at least partially covering an entrance to a macrochannel of the target lost circulation zone.

A well tool device (1) comprising a housing (10) having a through channel (11) with a first end (11a) and a second end (11b), said housing (10) further comprises a breakable ball seat (15), wherein a drop ball (17) received in the ball seat (15) partially or fully closes fluid communication in the through channel (11) of the housing (10). The breakable ball seat (15) is made of brittle and/or tempered glass, wherein the ball seat (15) is broken by a pressure build up in the housing (10) forcing the ball seat (15) against one or more disintegrating means (16), said disintegrating means (16) are provided as inside protrusions in the through channel (11).

A dissolvable untethered object for use inside a well fluid includes an internal cavity and a fluid entry point. The internal cavity contains a gas. The fluid entry point is closed and selectively openable so that the internal cavity can be filled with the well fluid flowing through the fluid entry point. A dissolving rate of the dissolvable untethered object is modified after contact of the well fluid inside the internal cavity with the dissolvable untethered object.

A sealing assembly for a dissolvable bridge plug, a dissolvable bridge plug and a sealing method for a gap are disclosed. The sealing assembly for dissolvable bridge plug includes a seal ring and a support ring. The support ring includes at least two supporting parts capable of sliding in the radial direction relative to each other. An axial end face of the support ring is butted with an axial end face of the seal ring. Respective central holes of the support ring and the seal ring are capable of being sleeved outside a component of dissolvable bridge plug. The supporting parts of the support ring in an expansion state are capable of exerting an axial thrust on the seal ring to prevent the seal ring from deforming in the axial direction.

A breaker composition comprising: (i) an acid precursor, (ii) a delaying agent and (iii) an aqueous fluid wherein the breaker composition has an effective operating temperature range of from about 25° C. to about 180° C. A wellbore servicing system comprising (a) an aqueous-based drilling fluid, wherein the aqueous-based drilling fluid forms water-wet solids in the wellbore; and (b) a breaker composition comprising (i) an acid precursor, (ii) a delaying agent and (iii) an aqueous fluid. A method of dissolving a filtercake comprising contacting the filtercake with a breaker solution comprising (i) an acid precursor, (ii) a delaying agent and (iii) an aqueous fluid wherein the filtercake comprises calcium carbonate.

A method for actuation of a downhole device includes rotating a drill pipe relative to a cylindrical pipe disposed coaxially within the drill pipe. First segments including a first material are disposed on the inner surface of the drill pipe. Second segments including a degradable material are disposed on the outer surface of the cylindrical pipe, with each of the second segments aligned with a corresponding first segment. The first material and the degradable material are insoluble in the downhole fluid, and a solubility of the degradable material in a solvent is greater than a solubility of the first material in the solvent. The method includes generating a first electrical signal pattern during rotation of the drill pipe; introducing the solvent into the drill pipe, in which the degradable material degrades responsive to introduction of the solvent; and generating a second electrical signal pattern after introduction of the solvent.

A method for treating a subterranean formation utilizing a slurry having a plurality of shrinkable material. The method of treatment may include a diversion treatment during a fracturing operation. The shrinkable material may be adapted to shrink in response to a temperature change. The slurry may be used to perform a plugging of a perforation or fracture in the formation.

A breaker composition comprising (i) a first acid precursor, (ii) a second acid precursor and (iii) an aqueous fluid wherein the first acid precursor has an effective operating temperature of from about 15° C. to about 120° C. and the second acid precursor has an effective operating temperature of from about 30° C. to about 180° C.

An improved wiper plug and methods of using the plug during casing and cementing operations within a subterranean wellbore are provided. The present plugs may pre-loaded with at least one engineered material and operative to release the material over time at a target location within the wellbore, such release serving to enhance the degradation of dissolvable components within the plugs and/or within the casing string, and/or to alter the chemical properties of the wellbore environment.

Apparatuses, systems, and methods of use are provided for a drilling stabilizer with chemical compartments within the teeth of the drilling stabilizer. The drilling stabilizer features dissolvable windows that allow chemicals to flow from the chemical compartments into the wellbore. The chemicals released can include cross-linkers or activators, which can react with polymers downhole to generate a plug for fluid loss control.