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(11)

EP 2 176 498 A2

(12)

(88) Date of publication A3: 05.03.2009 (43) Date of publication: 21.04.2010 Bulletin 2010/16 (21) Application number: 08781770.6 (22) Date of filing: 14.07.2008

(51) International Patent Classification (IPC):  E21B 10/22(2006.01) (86) International application number: PCT/US2008/069925 (87) International publication number: WO 2009/012196 (22.01.2009 Gazette 2009/04)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR Designated Extension States: AL BA MK RS (30) Priority: 13.07.2007 US 949756 P (71) Applicant: Baker Hughes Incorporated Houston, TX 77027 (US)

(72) Inventors: ZAHRADNIK, Anton, F. Sugarland, TX 77479 (US) KOLTERMANN, Terry, J. The Woodlands, TX 77381 (US) DICK, Aaron, J. Houston, TX 77008 (US) NGUYEN, Don, Q. Houston, TX 77066 (US) SULLIVAN, Eric, C. Houston, TX 77089 (US) RICKS, Gregory, L. Spring, TX 77386 (US) (74) Representative: Hano, Christian et al v. Füner Ebbinghaus Finck Hano Patentanwälte Mariahilfplatz 3 81541 München 81541 München (DE)