(19)

(11)

EP 2 576 965 A2

(12)

(88) Date of publication A3: 03.01.2013 (43) Date of publication: 10.04.2013 Bulletin 2013/15 (21) Application number: 11723197.7 (22) Date of filing: 26.05.2011

(51) International Patent Classification (IPC):  E21B 33/072(2006.01) (86) International application number: PCT/GB2011/050997 (87) International publication number: WO 2011/148184 (01.12.2011 Gazette 2011/48)

(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: 26.05.2010 GB 201008845 (71) Applicant: Quality Intervention AS 6899 Balestrand (NO)	(72) Inventor: ALVAERN, Jostein N-6899 Balestrand (NO) (74) Representative: Piésold, Alexander James  Dehns St Bride's House 10 Salisbury Square London EC4Y 8JD London EC4Y 8JD (GB)