Patent ID: 7753114

Claim:
A wellbore cleaning tool for removing ferromagnetic debris from a wellbore, comprising: a tool body configured to attach to a work string and having a longitudinal axis; a plurality of circumferential ridges axially spaced along said tool body, each ridge comprising: an apex parallel to said longitudinal axis, a first circumferential side surface angled with respect to and extending between said apex and the tool body, the first side surface having a first plurality of cavities formed therein, and a second circumferential side surface opposing said first side and angled with respect to and extending between said apex and the tool body, the second circumferential side surface having a second plurality of cavities formed therein wherein each cavity of the first plurality of cavities and each cavity of the second plurality of cavities being configured to house therein a respective different one magnet of a plurality of magnets; and a plurality of circumferential collection areas located between adjacent ridges, wherein an outer diameter of said plurality of circumferential collection areas is smaller than an outer diameter of the plurality of circumferential ridges.