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EP 4 798 743 A1

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(43) Date of publication: 02.09.2026 Bulletin 2026/36 (21) Application number: 24776613.2 (22) Date of filing: 30.09.2024

(51) International Patent Classification (IPC):  C21B 7/16(2006.01) F27B 3/22(2006.01) C21C 5/46(2006.01) F27B 1/16(2006.01) F27D 3/16(2006.01) C21C 5/48(2006.01) (52) Cooperative Patent Classification (CPC): C21B 7/163; F27D 3/16; C21C 5/48; F27B 1/16; C21C 5/4606; F27B 3/22 (86) International application number: PCT/EP2024/077412 (87) International publication number: WO 2025/087651 (01.05.2025 Gazette 2025/18)

(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: GE KH MA MD TN (30) Priority: 24.10.2023 LU 505347 (71) Applicant: Paul Wurth S.A. 1122 Luxembourg (LU)	(72) Inventors: SONNTAG, Daniel 54453 Nittel (DE) KRÄMER, Philipp 54290 Trier (DE) DE GRUITER, Christian 3313 Bergem (LU) (74) Representative: Office Freylinger  P.O. Box 48 8001 Strassen 8001 Strassen (LU)