Abstract: Subsea controlled milling apparatus and methods. In a described embodiment, a method of controlling displacement of a cutting device conveyed on a tubular string in a subterranean well includes the steps of: interconnecting an apparatus in the tubular string, the apparatus including an axial advancement device and an anchoring device; actuating the anchoring device to anchor the apparatus in the well; applying a pressure differential to the advancement device, thereby displacing the cutting device relative to the apparatus; and operating the cutting device to cut a structure in the well.

Abstract: Subsea controlled milling apparatus and methods. In a described embodiment, a method of controlling displacement of a cutting device conveyed on a tubular string in a subterranean well includes the steps of: interconnecting an apparatus in the tubular string, the apparatus including an axial advancement device and an anchoring device; actuating the anchoring device to anchor the apparatus in the well; applying a pressure differential to the advancement device, thereby displacing the cutting device relative to the apparatus; and operating the cutting device to cut a structure in the well.

Abstract: A wellbore junction isolation method and associated apparatus provide convenient isolation of a wellbore junction while permitting certain operations to be performed in a main or branch wellbore below the junction. In described embodiments, formations intersected by a main or branch wellbore below a wellbore junction may be stimulated by fracturing after installing an assembly at the wellbore junction, in a straddling and sealing relationship therewith, to isolate it from pressures applied during the fracturing operation. The illustrated isolation assembly may be installed in a single trip into the main wellbore.

Abstract: A wellbore junction isolation method and associated apparatus provide convenient isolation of a wellbore junction while permitting certain operations to be performed in a wellbore below the junction. In a described embodiment, a formation intersected by a main wellbore below a wellbore junction is stimulated by fracturing after installing an assembly at the wellbore junction to isolate it from pressures applied during the fracturing operation. In this embodiment, the assembly is installed in a single trip into the main wellbore.

Abstract: A wellbore junction isolation method and associated apparatus provide convenient isolation of a wellbore junction while permitting certain operations to be performed in a main or branch wellbore below the junction. In described embodiments, formations intersected by a main or branch wellbore below a wellbore junction may be stimulated by fracturing after installing an assembly at the wellbore junction, in a straddling and sealing relationship therewith, to isolate it from pressures applied during the fracturing operation. The illustrated isolation assembly may be installed in a single trip into the main wellbore.

Abstract: An apparatus and method for directing a first and a second object into a primary and a secondary borehole respectively from a main borehole communicating therewith at a borehole junction. The apparatus includes a deflector for positioning at the borehole junction to direct the first and second objects into the primary and secondary boreholes. A retainer holds the objects relative to each other such that when the first object is aligned to be directed into the primary borehole, the second object is aligned to be directed into the secondary borehole. A retainer orienting mechanism orients the retainer relative to the borehole junction so that the objects are aligned to be directed into the boreholes. The method includes positioning the deflector at the borehole junction and inserting the objects and the retainer into the main borehole. The retainer is oriented relative to the borehole junction so that the objects are aligned to be directed into their respective boreholes.