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(11)

EP 2 539 658 A2

(12)

(88) Date of publication A3: 19.01.2012 (43) Date of publication: 02.01.2013 Bulletin 2013/01 (21) Application number: 11748056.6 (22) Date of filing: 24.02.2011

(51) International Patent Classification (IPC):  F26B 19/00(2006.01) E21B 7/00(2006.01) E21B 21/00(2006.01) (86) International application number: PCT/US2011/026059 (87) International publication number: WO 2011/106514 (01.09.2011 Gazette 2011/35)

(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 (30) Priority: 25.02.2010 US 308166 P (71) Applicant: M-I LLC Houston, TX 77072 (US)

(72) Inventors: GUILLORY, Richard Brouwssard LA 70518 (US) DAVID, Kyle Scott LA 70583 (US) GARBER, Jake Youngsville LA 70592 (US) DOMAN, Aaron Youngsville LA 70592 (US) LAGASCA, Michael Rayne LA 70578 (US) KENNERSON, Dwayne Scott LA 70583 (US) ARDOIN, Chad Roanoke LA 70581 (US) PREJEAN, Dustin Scott LA 70583 (US) (74) Representative: Gill, Stephen Charles et al Mewburn Ellis LLP 33 Gutter Lane London EC2V 8AS London EC2V 8AS (GB)