(19)

(11)

EP 4 680 832 A1

(12)

(43) Date of publication: 21.01.2026 Bulletin 2026/04 (21) Application number: 23713951.4 (22) Date of filing: 14.03.2023

(51) International Patent Classification (IPC):  E21B 34/06(2006.01) E21B 7/06(2006.01) F16K 31/00(2006.01) F16K 11/00(2006.01) (52) Cooperative Patent Classification (CPC): E21B 34/06; E21B 7/06 (86) International application number: PCT/GB2023/050600 (87) International publication number: WO 2024/189300 (19.09.2024 Gazette 2024/38)

(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 ME MK MT NL NO PL PT RO RS SE SI SK SM TR Designated Extension States: BA Designated Validation States: KH MA MD TN (71) Applicant: AMB-REB LLC Conroe TX 77303 (US)	(72) Inventor: HUTTON, Richard Bristol Avon BS16 7FR (GB) (74) Representative: Baldwin, Mark  Firebird IP 27 Old Gloucester Street London WC1N 3AX London WC1N 3AX (GB)