(19)

(11)

EP 2 373 870 A2

(12)

(88) Date of publication A3: 26.08.2010 (43) Date of publication: 12.10.2011 Bulletin 2011/41 (21) Application number: 09796361.5 (22) Date of filing: 11.12.2009

(51) International Patent Classification (IPC):  E21B 41/04(2006.01) (86) International application number: PCT/EP2009/066918 (87) International publication number: WO 2010/066874 (17.06.2010 Gazette 2010/24)

(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 MK MT NL NO PL PT RO SE SI SK SM TR (30) Priority: 12.12.2008 EP 08171591 (71) Applicant: Welltec A/S 3450 Allerød (DK)	(72) Inventor: HALLUNDBÆK, Jørgen DK-3230 Græsted (DK) (74) Representative: Hoffmann Dragsted A/S  Rådhuspladsen 16 1550 Copenhagen V 1550 Copenhagen V (DK)