Patent ID: 7934552

Claim:
A method to seal well casing perforations and fluidic channels between said casing and surrounding wellbore formation utilizing a fusible metal alloy material, whereby the inside bore surface of the alloy sealing material upon re-solidification is left flush to the net casing bore surface after the completion of a single pass deployment process utilizing a wireline suspended downhole tool whereby: a control and telemetry electronics system provides two way, data and command serial communication between a topside power control unit and the downhole tool; and at least one independently controlled electric heater is configured to melt metal alloy material and to heat the wellbore formation zone surrounding said well casing; and a dispenser mechanism to carry a supply of solid metal alloy material and selectively dispense the same for melting; and at least one independently actuated inflatable bladder to expand and retract by means of an actuation source contained within the tool; and wherein the tool comprises overflow portals configured to recover and remove excess amounts of said alloy upon extraction of said downhole tool; wherein the following sequence is performed: said downhole tool is lowered as an assembly into said well casing by means of a wireline; and upon reaching a desired location within the casing, one of said at least one inflatable bladder located a bottom of said tool is inflated to expand to form a temporary plug; and a quantity of alloy material contained in said downhole tool is dispensed into said at least one heater which is energized to melt said alloy material and to radially heat the surrounding casing and wellbore formation to a desired temperature to thereby form a molten alloy mass surrounding the downhole tool, casing perforations and space between the casing and the surrounding wellbore formation; and upon a accumulating a desired quantity of molten alloy between said downhole tool and said well casing, another one or more of said at least one bladders are inflated within the space between the tool and casing bore surfaces to squeeze and thereby displace the molten alloy upwards between said downhole tool and the inside surface of said well casing and; upwardly displaced molten alloy is allowed to spill through overflow portals and into a receptacle contained within said downhole tool for subsequent removal as excess material; and while said one or more bladders are inflated to squeeze and displace said molten alloy, said alloy melting heater is de-energized thereby allowing the alloy to cool and solidify; and upon resolidification of the alloy, said inflated bladder, which formed said temporary plug is deflated, thereby allowing said downhole tool to be removed from the well casing while leaving well casing perforations sealed flush to net bore surface.