(19)

(11)

EP 3 997 305 A1

(12)

(43) Date of publication: 18.05.2022 Bulletin 2022/20 (21) Application number: 19937754.0 (22) Date of filing: 12.07.2019

(51) International Patent Classification (IPC):  E21B 43/27(2006.01) E21B 43/28(2006.01) E21B 43/22(2006.01) E21B 43/285(2006.01) (52) Cooperative Patent Classification (CPC): E21B 37/06; E21B 37/08; E21B 43/255 (86) International application number: PCT/CA2019/050970 (87) International publication number: WO 2021/007645 (21.01.2021 Gazette 2021/03)

(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 Designated Validation States: KH MA MD TN (71) Applicant: Lamrock Canada Incorporated Calgary, Alberta T3L 2P5 (CA)	(72) Inventor: BRENNAN, Jordan Calgary, Alberta T3L 2P5 (CA) (74) Representative: Herrero & Asociados, S.L.  Cedaceros, 1 28014 Madrid 28014 Madrid (ES)