(19)

(11)

EP 4 263 999 A1

(12)

(43) Date of publication: 25.10.2023 Bulletin 2023/43 (21) Application number: 21840543.9 (22) Date of filing: 16.12.2021

(51) International Patent Classification (IPC):  E21B 7/24(2006.01) E21B 28/00(2006.01) E21B 17/10(2006.01) E21B 34/12(2006.01) (52) Cooperative Patent Classification (CPC): E21B 7/24; E21B 17/10; E21B 28/00; E21B 34/12; E21B 17/1064 (86) International application number: PCT/EP2021/086311 (87) International publication number: WO 2022/129412 (23.06.2022 Gazette 2022/25)

(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 (30) Priority: 16.12.2020 GB 202019918 13.05.2021 GB 202106868 (71) Applicant: Rotojar Innovations Limited Aberdeen AB21 0EU (GB)	(72) Inventor: MOYES, Peter Barnes Aberdeen AB21 0EU (GB) (74) Representative: Marks & Clerk LLP  15 Fetter Lane London EC4A 1BW London EC4A 1BW (GB)