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(11)

EP 2 864 572 A2

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(88) Date of publication A3: 07.08.2014 (43) Date of publication: 29.04.2015 Bulletin 2015/18 (21) Application number: 13734913.0 (22) Date of filing: 21.06.2013

(51) International Patent Classification (IPC):  E21B 7/06(2006.01) E21B 7/10(2006.01) (86) International application number: PCT/US2013/047054 (87) International publication number: WO 2013/192524 (27.12.2013 Gazette 2013/52)

(84) Designated Contracting States: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA ME (30) Priority: 22.06.2012 US 201213530298 (71) Applicant: Hunt Advanced Drilling Technologies L.L.C. Dallas, TX 75201 (US)	(72) Inventors: BENSON, Todd, W. Dallas, TX 75201 (US) CHEN, Teddy, C. Austin, TX 78731 (US) (74) Representative: UEXKÜLL & STOLBERG  Patentanwälte Beselerstrasse 4 22607 Hamburg 22607 Hamburg (DE)