WELLBORE CLEANING TOOL FOR CLEANING FERROUS MATERIAL AND METHOD THEREFOR

摘要

There is disclosed a cleaning tool for use in cleaning ferrous material from a wellbore, a cleaning assembly comprising a tool main body and, at least, one magnet mounted for selective movement relative to the main body between deactivated and activated positions and held in the deactivated position radially inside relative to the tool main body and in the activated position radially outside relative to the tool main body. An assembly for use in cleaning ferrous material from a wellbore comprises a plurality of such wellbore cleaning tools. A drilling or milling string comprises a drilling or milling tool and a cleaning tool. A method of cleaning ferrous material from a wellbore, the method comprising the steps of: running a cleaning tool into a wellbore to be cleaned with a magnet of the cleaning tool in a deactivated position; moving the magnet from the deactivated position to an activated position by moving it radially outside relative to the main body; and translating the cleaning tool relative to the wellbore to collect ferrous material present in the wellbore.