Abstract: A method of preventing fluid flow past a tapered face of a mill diverter in a wellbore comprises: positioning the mill diverter in the wellbore, wherein the mill diverter comprises: a body; the tapered face, wherein the tapered face is located at one end of the body; and a swellable material, wherein the swellable material: is positioned circumferentially around the body of the mill diverter adjacent to the tapered face; swells in the presence of a swelling fluid; and prevents substantially all of a fluid from flowing past the swellable material after the swellable material has swelled; and causing or allowing the swellable material to swell. The swellable material can also prevent a loss of pressure in the wellbore above the swellable material or prevent a first fluid having a first density from mixing with a second fluid having a second density after the swellable material has swelled.

Abstract: A method of preventing fluid flow past a tapered face of a mill diverter in a wellbore comprises: positioning the mill diverter in the wellbore, wherein the mill diverter comprises: a body; the tapered face, wherein the tapered face is located at one end of the body; and a swellable material, wherein the swellable material: is positioned circumferentially around the body of the mill diverter adjacent to the tapered face; swells in the presence of a swelling fluid; and prevents substantially all of a fluid from flowing past the swellable material after the swellable material has swelled; and causing or allowing the swellable material to swell. The swellable material can also prevent a loss of pressure in the wellbore above the swellable material or prevent a first fluid having a first density from mixing with a second fluid having a second density after the swellable material has swelled.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.

Abstract: Specially designed apparatus is utilized to provide convenient isolation of a wellbore junction from pressure and corrosion during an acid fracturing stimulation process performed in a main or branch wellbore portion downhole from the junction. The apparatus has an outer tubular portion which may be installed, in a single trip into the main wellbore, in a straddling and sealing relationship with the junction, and an inner tubular structure sealingly and removably received within the outer tubular structure. Fracturing acid may be pumped directly down the main wellbore, and then to the formation to be stimulated, via the interior of the outer tubular structure, after the removal of the inner tubular structure subsequent to its use in facilitating a downhole pressure test of a lower end seal portion of the outer tubular structure.

Abstract: Specially designed apparatus is utilized to provide convenient isolation of a wellbore junction from pressure and corrosion during an acid fracturing stimulation process performed in a main or branch wellbore portion downhole from the junction. The apparatus has an outer tubular portion which may be installed, in a single trip into the main wellbore, in a straddling and sealing relationship with the junction, and an inner tubular structure sealingly and removably received within the outer tubular structure. Fracturing acid may be pumped directly down the main wellbore, and then to the formation to be stimulated, via the interior of the outer tubular structure, after the removal of the inner tubular structure subsequent to its use in facilitating a downhole pressure test of a lower end seal portion of the outer tubular structure.

Abstract: An expanding wellbore junction system, apparatus and methods are provided for forming a sealed wellbore intersection in a subterranean well. In one. described method, an expandable wellbore junction is expanded within an under-reamed cavity in a wellbore. Intersecting tubular legs of the wellbore junction are then drifted using a drifting apparatus. A deflection device may be used to direct a drift of the drifting apparatus into a selected one of the wellbore junction legs.