(19)

(11)

EP 2 670 944 A2

(12)

(88) Date of publication A3: 03.01.2013 (43) Date of publication: 11.12.2013 Bulletin 2013/50 (21) Application number: 12700581.7 (22) Date of filing: 13.01.2012

(51) International Patent Classification (IPC):  E21B 34/06(2006.01) E21B 47/06(2012.01) E21B 41/00(2006.01) (86) International application number: PCT/GB2012/000026 (87) International publication number: WO 2012/104574 (09.08.2012 Gazette 2012/32)

(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: 31.01.2011 GB 201101566 (71) Applicant: Tendeka B.V. Altens, Aberdeen AB12 3HT (GB)	(72) Inventors: ANDERSON, Neil Insch Aberdeenshire AB52 6NQ (GB) PITMAN, Malcolm Milltimber Aberdeen AB13 0EN (GB) (74) Representative: Docherty, Andrew John  Marks & Clerk LLP Aurora 120 Bothwell Street Glasgow G2 7JS Glasgow G2 7JS (GB)