Abstract: A gas-actuated dump bailer tool that can be opened/closed under the direct or indirect action of gas generated by a gas-generating chemical reaction mixture housed within the dump bailer. Additionally, a downhole tool assembly that employs the dump bailer together associated methods of using the dump bailer downhole in an oil/gas well.

Abstract: A multi-trip method of repairing a leaking annular seal located within an annulus that encircles an oil/gas wellbore tubular body, examples of such seals including annular packers or cement seals. The method comprises providing deflector within a wellbore tubular body adjacent to one or more openings in the wall of the tubular body. Alloy beads are then deployed downhole via the tubular body so that the alloy beads are deflected via said openings into the annulus where they accumulate on top of the annular seal. A heating tool is then operated to heat the alloy within the annulus to form an alloy plug above the annular seal. The present invention also provides various pieces of downhole equipment for use in the repair method of the invention.

Abstract: A single trip method of repairing a leaking annular seal located within an annulus that encircles an oil/as wellbore tubular body, examples of such seals including annular packers or cement seals. The method comprises providing deflector within a wellbore tubular body adjacent to one or more openings in the wall of the tubular body. Alloy beads are then deployed downhole via the tubular body so that the alloy beads are deflected via said openings into the annulus where they accumulate on top of the annular seal. The alloy is then heated to form an alloy plug above the annular seal. The present invention also provides an annular seal repair tool assembly for use in the repair method of the present invention.

Abstract: Methods to repair leaking liner hangers and/or drop off liner assemblies utilizing heaters to melt metal alloys which will solidify and form an annular seal at the liner hanger and seal the leak. Such methods may be used in numerous liner hanger environments, including but not limited to, well bores with and without tieback assemblies.

Abstract: The present invention provides a downhole heating tool with an increased heating capacity for use in setting alloy plugs/seal in downhole target regions of wellbores, such as oil/gas wells. The increased heating capacity enables greater quantities of alloy to be melted in one operation. It also enables alloys with higher melting points to be melted in the downhole environment. To this end the heating tool comprises a plurality of discrete tubular heating units linked together by connection means that permit the movement of the tubular heating units relative to one another. The relative freedom of movement between the heating units facilitates a transition between a deployment configuration, in which the heating tool is optimised for deployment downhole, and a heating configuration, in which the heating tool adopts an expanded heating footprint within a downhole target region.