Apparatus for completing a subterranean wellbore and associated methods of using provide relatively uncomplicated and convenient access to a parent wellbore lower portion from a lateral wellbore liner which extends into the parent wellbore above the lower portion. The apparatus is utilized to form an opening through a portion of the liner which overlies the parent wellbore lower portion, thereby providing access thereto. In a preferred embodiment, the apparatus includes a milling guide having an axially extending guide profile formed therein, which guide profile is capable of directing a mill toward the liner portion to form the opening. The milling guide is capable of being anchored in the liner to thereby fix its axial and rotational alignment relative to the liner portion.

Apparatus for forming a window or the outline of a window in the casing of a cased wellbore comprises thermal means for forming a window or an outline of a window in said casing and locating means for positioning the thermal means in the casing. The thermal means comprises an oxidation chamber (561) having at least one outlet (562), arranged so that reaction materials (565) in the oxidation chamber react to produce sufficient heat to cause a heat jet to exit through the at least one outlet.

Apparatus for completing a subterranean wellbore and associated methods of using provide relatively uncomplicated and convenient access to a parent wellbore lower portion from a lateral wellbore liner which extends into the parent wellbore above the lower portion. The apparatus is utilized to form an opening through a portion of the liner which overlies the parent wellbore lower portion, thereby providing access thereto. In a preferred embodiment, the apparatus includes a milling guide having an axially extending guide profile formed therein, which guide profile is capable of directing a mill toward the liner portion to form the opening. The milling guide is capable of being anchored in the liner to thereby fix its axial and rotational alignment relative to the liner portion.

A high-speed chemical drill (20) for removing portions of a target material (30), comprises: an elongated tube (21) formed of a fuel material; a source (24) of oxidizer; a conduit (26) for establishing a controllable flow of oxidizer from said source through said tube (21); and a sleeve (28) formed of a material containing chlorine and/or fluorine mounted on said tube (21); whereby, when said drill (20) is ignited and used to remove portions of a target material (30), the chlorine and/or fluorine in said sleeve (28) material will react chemically with the target material (30) to form gaseous reaction products.

A collapsible cutter (10) that utilizes opposing collapsible assemblies having explosive charges (200,300) coupled thereto. The collapsible cutter ( 10) has an linear actuator(100) with a running position and a deployed position. Secured to the actuator (100) is a first plurality of remotely-detonatable charges (200) that are pivotally coupled to the actuator (100) such that the first plurality of remotely-detonatable charges (100) are splayed outward and toward a median of the actuator (100) as the actuator (100) moves from the running position to the deployed position. Also secured to the actuator (100) is a second plurality of remotely-detonatable charges (300) that are pivotally coupled to an opposing end, the second plurality of remotely-detonatable charges (300) are splayed outward and toward the median of the actuator (100) as the actuator (100) moves from the running position to the deployed position. As the actuator (100) continues to move to the deployed position, the first and the second plurality of remotely-detonatable charges (200,300) are placed in a meshed-relation. In this manner, a substantially contiguous cutting profile is defined with the first and the second plurality of charges (200,300).

Apparatus for forming a window or the outline of a window in the casing of a cased wellbore comprises thermal means for forming a window or an outline of a window in said casing and locating means for positioning the thermal means in the casing. The thermal means comprises an oxidation chamber (561) having at least one outlet (562), arranged so that reaction materials (565) in the oxidation chamber react to produce sufficient heat to cause a heat jet to exit through the at least one outlet.

A collapsible cutter (10) that utilizes opposing collapsible assemblies having explosive charges (200,300) coupled thereto. The collapsible cutter ( 10) has an linear actuator(100) with a running position and a deployed position. Secured to the actuator (100) is a first plurality of remotely-detonatable charges (200) that are pivotally coupled to the actuator (100) such that the first plurality of remotely-detonatable charges (100) are splayed outward and toward a median of the actuator (100) as the actuator (100) moves from the running position to the deployed position. Also secured to the actuator (100) is a second plurality of remotely-detonatable charges (300) that are pivotally coupled to an opposing end, the second plurality of remotely-detonatable charges (300) are splayed outward and toward the median of the actuator (100) as the actuator (100) moves from the running position to the deployed position. As the actuator (100) continues to move to the deployed position, the first and the second plurality of remotely-detonatable charges (200,300) are placed in a meshed-relation. In this manner, a substantially contiguous cutting profile is defined with the first and the second plurality of charges (200,300).

Apparatus and method for forming an opening from a first wellbore (36f) to a second wellbore (38f). The apparatus includes a milling guide (190) having an axially extending guide profile (196) formed therein, which guide profile is capable of directing a mill (198) toward a liner (28f) extending across the second wellbore (38f). The milling guide (190) is capable of being anchored in the liner (28f) to thereby fix its axial and rotational alignment relative to the liner (28f). The milling guide (190) is anchored by a gripping structure (202) that is capable of radially outwardly engaging the liner (28f).

Apparatus and method of forming an opening between a first wellbore (36g) and a second wellbore (38g). The apparatus includes a milling guide (248) having a guide profile (250) formed thereon which is operative to guide a cutting tool (252) to contact a liner (28g). An anchor portion (202g) of the milling guide (248) grippingly engages the liner (28g) to axially and rotationally align the milling guide (248) with the liner (28g).

Apparatus and method for forming an opening from a first wellbore (36d) to a second wellbore (38d). The apparatus includes a milling guide (136) having a guide profile (142) formed thereon for directing a cutting tool (138) to contact the liner (28d) extending across the second wellbore (38d). The milling guide is cooperatively engageable with an anchor (140) to axially and radially align the guide profile (142) with a portion of the liner (28d).

A downhole chemical cutting tool (7) for use within a well bore (1) for cutting very small diameter tubular goods, has an elongated tool body having anchoring means (14) for anchoring the cutting tool within a conduit (4), and a pressure generating section (11). A cutting section (18) of the tool has a longitudinally extending bore therein having at least one cutting port (20) for expelling cutting agent to perform a cutting function. A chemical section in the tool body is interposed between the pressure generating section and the cutting section, and is formed of a casing (16) having a chamber containing a source of fluid chemical cutting agent. The tool further comprises closure means at at least one end of the casing for closing the chamber, the closure means comprising a diaphragm body (23) which is inserted into one end of the casing by an interference fit and which has spaced transverse rupture diaphragms.

A compensator 1 for supporting an explosive severing device 2 in a bore hole 3 below a well head (not shown) and for damping forces arising on explosion of the explosive severing device 2 in the bore hole. The compensator 1 comprises two parts 4 (Figs. 1 to 4) and 5 (Figs. 5 and 6) mounted for relative longitudinal slidable motion. One part 4 has means 6 for supporting the explosive device 2 in the bore hole 3, and at least one of the parts (in this case both parts 4 and 5) has means in the form of through holes 7 for dissipating laterally, upwardly directed forces arising on explosion of the device in the bore hole.