(19)

(11)

EP 2 580 423 A2

(12)

(88) Date of publication A3: 12.04.2012 (43) Date of publication: 17.04.2013 Bulletin 2013/16 (21) Application number: 11727339.1 (22) Date of filing: 10.06.2011

(51) International Patent Classification (IPC):  E21B 43/01(2006.01) (86) International application number: PCT/NO2011/000170 (87) International publication number: WO 2011/155848 (15.12.2011 Gazette 2011/50)

(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: 10.06.2010 NO 20100830 (71) Applicant: Borealis Offshore Consultants AS 0764 Oslo (NO)	(72) Inventor: FREUND, Rene Pascal Emile N-0764 Oslo (NO) (74) Representative: Gustad, Trond  Oslo Patentkontor AS P.O. Box 7007 M 0306 Oslo 0306 Oslo (NO)