(19)
(11) EP 4 405 561 A1

(12)

(43) Date of publication:
31.07.2024 Bulletin 2024/31

(21) Application number: 22740518.0

(22) Date of filing: 23.06.2022
(51) International Patent Classification (IPC): 
E21B 21/10(2006.01)
(52) Cooperative Patent Classification (CPC):
E21B 21/106; E21B 2200/03
(86) International application number:
PCT/IB2022/055842
(87) International publication number:
WO 2023/041993 (23.03.2023 Gazette 2023/12)
(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: 20.09.2021 US 202117479032

(71) Applicant: Weatherford Technology Holdings, LLC
Houston Texas 77056 (US)

(72) Inventors:
  • NORTHAM, Paul R.
    Houston, Texas 77056 (US)
  • DILLARD, Walter S.
    Houston, Texas 77041 (US)

(74) Representative: Marks & Clerk LLP 
15 Fetter Lane
London EC4A 1BW
London EC4A 1BW (GB)

   


(54) MANAGED PRESSURE DRILLING CONTROL SYSTEM WITH CONTINUOUSLY VARIABLE TRANSMISSION