Degradable downhole tools, tool components, and balls are formed from a processed polyvinyl alcohol (PVA) compound that is degradable in a high-salinity environment. The PVA compound exhibits strength and elasticity properties that are comparable to existing degradable downhole polymers and further exhibits degradability properties that are superior to existing degradable downhole polymers, particularly in high-salinity fluids. For different components, the PVA compound may include a reinforcing material such as fiberglass. The PVA compound also includes a loading of degradable metal, such as a degradable magnesium alloy, rendering the material degradable at high salinity. Usage of tools, tool components, and balls formed from the disclosed materials eliminates the requirement that such equipment be drilled out after use as the PVA compound quickly degrades in high-salinity downhole fluids.

A downhole device that drills a wellbore includes a stabilizer which has a body and blades. The blades are disposed on a surface of the body and each blade has a hollow space. The blades each include a dissolvable window that is disposed on a surface of each of the blades and a light source that emits light to the wellbore. The dissolvable window blocks light emitted from the light source thereby reducing or eliminating light from being transmitted to the wellbore. The dissolvable window dissolves upon exposure to a fluid containing a dissolving medium, thereby allowing the light source to transmit light to the wellbore. Methods of using the downhole device to activate downhole chemicals are also provided.

An arrangement for a buoyant liner or casing string including a shoe plug affixed to the string and configured to hold a pressure differential from a higher pressure outside of the string to a lower pressure inside of the string and to unseat upon a pressure differential of a higher pressure inside of the string to a pressure outside of the string.

A casing/liner string buoyancy arrangement including a casing/liner string, and a material defining a volume disposed within the string, the material excluding downhole fluids from the volume, the volume being of a lower specific gravity than the same downhole fluids. A method for managing buoyancy of a casing/liner string including configuring a casing/liner string, running the string, and selectively maintaining or degrading the material to adjust buoyancy of the string. A borehole system including a borehole in a subsurface formation, and an arrangement disposed in the borehole.

Systems and methods for instructing a device within a wellbore of a subterranean well includes a drill string with an actuator assembly extending into the subterranean. The actuator assembly has a first pipe member with a segment formed of a first material. A second pipe member is coaxially aligned with the first pipe member. A plurality of bearings are positioned between the first pipe member and the second pipe member. Each of the plurality of bearings includes a second material. The first material is reactive to the second material. Certain of the plurality of bearings are changeable bearings that include a dissolvable material. The actuator assembly is operable to instruct an operation of the device by generating an instruction signal by rotating the first pipe member relative to the second pipe member and interpreting a pattern of a reaction of the segment as a bearing rotates past the segment.

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 temporary well isolation device which has an axial passage that comprises a temporary housing having an internal cavity containing a chemical material and a temporary barrier or plug member that can be actuated by an external mechanism to allow fluid to flow into the internal chamber and contact the chemical material in the internal chamber. When the chemical material is exposed to fluid, the chemical material causes the temporary housing to corrode, dissolve, and/or degrade.

A system includes a sliding sleeve, a ball landing seat, a plurality of microchips, a hydraulic piston, and a ball catcher. The sliding sleeve is installed within a tubular body having an exit groove. The ball landing seat is formed by the sliding sleeve. The plurality of microchips are housed in a microchip ring installed within the sliding sleeve. The hydraulic piston is installed within the microchip ring and triggered by reception of a ball in the ball landing seat. The ball reduces a cross sectional area of a flow path while in the ball landing seat. The hydraulic piston releases the plurality of microchips through the exit groove and into the well to gather data. The ball catcher is configured to receive and hold the ball after the plurality of microchips are released into the well. The ball catcher and the ball are made of a dissolvable material.

A plug assembly includes a continuous expandable sealing ring having an embedded radial gap feature. The continuous expandable sealing ring includes a first section with a prominent external surface, whereby the first section with a prominent external surface includes a radial gap underneath, and a second section with a second external surface. During the setting of the plug, the first prominent external surface comes in contact with the internal surface of the tubing string, while the radial gap underneath allows avoiding transmitting radial forces from the continuous sealing ring towards the tubing string, therefore keeping the majority of the force transmission from the expandable gripping ring towards the tubing string.

A downhole sub has a body defined by a wall extending in an axial direction from a first end to a second end. An inner surface of the wall defines a flow path through the downhole sub and an outer surface of the wall defines an outer diameter of the downhole sub. A compartment extends from the outer surface into the wall to having a depth less than a thickness of the wall. A housing may be removably fixed in the compartment. One or more mobile devices may be disposed in the housing. Each of the one or more mobile devices includes a sensor encapsulated in a protective material. A control element may block an opening of the housing, the control element is made of a dissolvable material configured to dissolve at a predetermined depth in a wellbore and release the one or more mobile devices into the wellbore.