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(11)

EP 2 524 104 A2

(12)

(88) Date of publication A3: 17.11.2011 (43) Date of publication: 21.11.2012 Bulletin 2012/47 (21) Application number: 11733247.8 (22) Date of filing: 11.01.2011

(51) International Patent Classification (IPC):  E21B 17/02(2006.01) F16L 25/00(2006.01) E21B 23/04(2006.01) E21B 17/06(2006.01) (86) International application number: PCT/US2011/020765 (87) International publication number: WO 2011/088013 (21.07.2011 Gazette 2011/29)

(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: 12.01.2010 US 294330 P (71) Applicants: Services Pétroliers Schlumberger 75007 Paris (FR) FR  Schlumberger Holdings Limited Tortola 1110 (VG) GB NL  Schlumberger Technology B.V. 2514 JG The Hague (NL) AL BG CZ DE DK GR HU IE IT LT NO PL RO SI SK TR  PRAD Research and Development Limited Road Town, Tortola 1110 (VG) AL AT BE CH CY EE ES FI HR IS LI LU LV MC MK MT PT RS SE SM  Schlumberger Technology Corporation Sugar Land, TX 77478 (US) IS

(72) Inventors: DU, Michael Hui Pearland Texas 77584 (US) RYTLEWSKI, Gary League City Texas 77573 (US) WANG, David Wei Sugar Land Texas 77479 (US) (74) Representative: Fortt, Simon Merton et al Schlumberger Cambridge Research Ltd IPL High Cross, Madingley Road Cambridge, Cambridgeshire CB3 0EL Cambridge, Cambridgeshire CB3 0EL (GB)