A plug for wellbore tubing includes: an internal portion; a first external portion which surrounds the internal portion; and a second external portion disposed axially adjacent to the first external portion, with respect to a central longitudinal axis of the plug. The second external portion expands to: engage an interior surface of the wellbore tubing in response to a trigger as the plug displaces downhole through the wellbore tubing; and open a passage to permit a fluid to progress to the first external portion. The first external portion expands to engage the wellbore tubing in response to the expansion of the second external portion and upon contact with the fluid. A related method includes providing such a plug, and displacing the plug downhole in the wellbore tubing.

Elongate capsules for housing waste are configured for disposal (placement) into wellbore(s) that are located in particular deep underground geologic formation(s). These capsules have opposing structures for physically linking multiple capsules together in an end-to-end fashion. These opposing end structures may include a stinger with pins at a top end of the capsule; and a J-slots structure at the bottom end of the capsule. The stinger with pins of a first capsule may be (removably) attached to the J-slots of a second capsule. Further, a retrieval-tool also has the J-slots structure at one end. The J-slots structure of the retrieval-tool may be configured to (removably) attach to a stinger with pins of a given capsule (which may be linked to other capsule(s)); and then the retrieval-tool may be used to retrieve the given capsule(s) from a given wellbore. Capsule retrieval systems and/or method may utilize such capsule(s) and the retrieval-tool.

Elongate capsules for housing waste are configured for disposal (placement) into wellbore(s) that are located in particular deep underground geologic formation(s). These capsules have opposing structures for physically linking multiple capsules together in an end-to-end fashion. These opposing end structures may include a stinger with pins at a top end of the capsule; and a J-slots structure at the bottom end of the capsule. The stinger with pins of a first capsule may be (removably) attached to the J-slots of a second capsule. Further, a retrieval-tool also has the J-slots structure at one end. The J-slots structure of the retrieval-tool may be configured to (removably) attach to a stinger with pins of a given capsule (which may be linked to other capsule(s)); and then the retrieval-tool may be used to retrieve the given capsule(s) from a given wellbore. Capsule retrieval systems and/or method may utilize such capsule(s) and the retrieval-tool.

Elongate capsules for housing waste are configured for disposal (placement) into wellbore(s) that are located in particular deep underground geologic formation(s). These capsules have opposing structures for physically linking multiple capsules together in an end-to-end fashion. These opposing end structures may include a stinger with pins at a top end of the capsule; and a J-slots structure at the bottom end of the capsule. The stinger with pins of a first capsule may be (removably) attached to the J-slots of a second capsule. Further, a retrieval-tool also has the J-slots structure at one end. The J-slots structure of the retrieval-tool may be configured to (removably) attach to a stinger with pins of a given capsule (which may be linked to other capsule(s)); and then the retrieval-tool may be used to retrieve the given capsule(s) from a given wellbore. Capsule retrieval systems and/or method may utilize such capsule(s) and the retrieval-tool.

Elongate capsules for housing waste are configured for disposal (placement) into wellbore(s) that are located in particular deep underground geologic formation(s). These capsules have opposing structures for physically linking multiple capsules together in an end-to-end fashion. These opposing end structures may include a stinger with pins at a top end of the capsule; and a J-slots structure at the bottom end of the capsule. The stinger with pins of a first capsule may be (removably) attached to the J-slots of a second capsule. Further, a retrieval-tool also has the J-slots structure at one end. The J-slots structure of the retrieval-tool may be configured to (removably) attach to a stinger with pins of a given capsule (which may be linked to other capsule(s)); and then the retrieval-tool may be used to retrieve the given capsule(s) from a given wellbore. Capsule retrieval systems and/or method may utilize such capsule(s) and the retrieval-tool.

A borehole fishing tool, including a grapple for fixedly attaching to a fish in a borehole, a tool housing to which the grapple is connected, and at least one camera, mounted in the tool housing, to generate at least one image of the fish in the borehole. The borehole fishing tool also includes at least one light source, mounted in the tool housing, to illuminating a portion of the borehole between the at least one camera and the fish, a connector attached to the tool housing to connect the tool housing to a conveyor, and a telemetry transceiver to transmit at least one image of the fish through a telemetry channel in the conveyor to a computer system at an Earth's surface.

An overshot apparatus includes a tubular housing and a grapple disposed within a bore of the tubular housing. The grapple has a central opening to receive a fish and is operable to grip an outer diameter of the fish. A stinger is supported in the bore by an adapter attached to an upper end of the tubular housing. The stinger is positioned to be inserted into the fish received in the central opening of the grapple. A packing element is positioned on an external surface of the stinger to engage an inner diameter of the fish when the stinger is inserted into the fish and the fish is received within the central opening of the grapple. The adapter and stinger have conduits for passage of fluid into the fish.

A well column pipe retrieval tool incorporating a “U” bracket having a lateral arm and an oppositely lateral arm, wherein the oppositely lateral arm has a fixed segment and a moveable segment; the column pipe retrieval tool further incorporating a column pipe receiving throat which is laterally bounded by the “U” bracket's lateral arm, and which is oppositely laterally bounded by the oppositely lateral arms' moveable segment; the column pipe retrieval tool further incorporating a plurality of pin and angled slide slot combinations which interconnect the oppositely lateral arm's fixed and moveable segments.

A well column pipe retrieval tool incorporating a “U” bracket having a lateral arm and an oppositely lateral arm, wherein the oppositely lateral arm has a fixed segment and a moveable segment; the column pipe retrieval tool further incorporating a column pipe receiving throat which is laterally bounded by the “U” bracket's lateral arm, and which is oppositely laterally bounded by the oppositely lateral arms' moveable segment; the column pipe retrieval tool further incorporating a plurality of pin and angled slide slot combinations which interconnect the oppositely lateral arm's fixed and moveable segments.

The present disclosure describes a cable head for a wireline tool that includes a housing that comprises an outlet opening for a wireline and an interface configured to connect the housing to the wireline tool; a spool rotatably mounted in the housing; an anchoring point configured for mechanical attachment to an end of the wireline; and a drive configured to rotate the spool and thereby wrap a portion of the wireline around the spool to and retract the wireline into the housing. A wireline tool and a method of retrieving a lost wireline tool are also described.