Conocophillips Company

Dale R Doherty

Randall Scott Shafer

David D Hearn

Curtis G Blount

Dan Thomas Mueller

Rick D Watts

Geir Ove Titlestad

Method of plugging a hydrocarbon well by a through-tubing technique are described. The method allows the tubing to be left in place. Only a short (<2 m) section is cut, milled, perforated, ruptured and expanded, or combinations thereof. A blocking device is sent downhole to block a bottom of the plug section, and bismuth alloy pellets dropped onto the blocking device. A heater is deployed to melt the bismuth alloy pellets. Next, the alloy liquid is allowed to cool and solidify. During solidification, the alloy expands and fills the section of well to be plugged or a portion thereof. Once primary and secondary barriers are in place, the well can be closed and the Christmas tree removed. A rock-to-rock plug can be set by removing or partially removing the tubular and outer casing, or just inner casing/tubulars can be removed if the exterior cement and casing are of sufficient quality.

Through tubing P AND A with bismuth alloys

Method of plugging a hydrocarbon well by a through-tubing technique are described. The method allows the tubing to be left in place. Only a short (&#x3c;2 m) section is cut, milled, perforated, ruptured and expanded, or combinations thereof. A blocking device is sent downhole to block a bottom of the plug section, and bismuth alloy pellets dropped onto the blocking device. A heater is deployed to melt the bismuth alloy pellets. Next, the alloy liquid is allowed to cool and solidify. During solidification, the alloy expands and fills the section of well to be plugged or a portion thereof. Once primary and secondary barriers are in place, the well can be closed and the Christmas tree removed. A rock-to-rock plug can be set by removing or partially removing the tubular and outer casing, or just inner casing/tubulars can be removed if the exterior cement and casing are of sufficient quality.

Through tubing P and A with bismuth alloys

Methods, systems, and devices for sealing stage tool leaks are disclosed. In one aspect a stage tool for wellbore cementing comprises an external stage tool body and a sliding sleeve within the external stage tool body configured to regulate cement flow through the stage tool. At least a portion of the sliding sleeve comprises a meltable alloy configured to seal a leak. The meltable alloy is configured to be melted by a heating source, flow into the leak, and resolidify as the melted alloy cools, thereby sealing the leak.

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Houston, TX, United States of America

Dale R Doherty