(19)

(11)

EP 2 954 156 A2

(12)

(88) Date of publication A3: 16.04.2015 (43) Date of publication: 16.12.2015 Bulletin 2015/51 (21) Application number: 14705859.8 (22) Date of filing: 06.02.2014

(51) International Patent Classification (IPC):  E21B 43/08(2006.01) E21B 43/26(2006.01) E21B 34/14(2006.01) E21B 43/12(2006.01) (86) International application number: PCT/GB2014/050338 (87) International publication number: WO 2014/122459 (14.08.2014 Gazette 2014/33)

(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 Designated Extension States: BA ME (30) Priority: 08.02.2013 GB 201302308 01.08.2013 US 201313956660 15.11.2013 US 201314081665 (71) Applicant: Petrowell Limited Aberdeen AB12 3LF (GB)	(72) Inventors: MCGEOCH, Andrew Aberdeen Aberdeenshire AB21 0DR (GB) GOODALL, Liam Watt Clark Edinburgh EH26 0LW (GB) STEWART, Sean Aberdeen Aberdeenshire AB21 0DR (GB) SLADIC, John Aberdeen Aberdeenshire AB21 0DR (GB) RABEL, Shawn Houston, Texas 77069 (US) (74) Representative: Moreland, David  Marks & Clerk LLP Aurora 120 Bothwell Street Glasgow G2 7JS Glasgow G2 7JS (GB)