US 12,188,303 B2
Multi-mode pumped riser arrangement and methods
Per Christian Stenshorne, Oslo (NO); David Edward Smith, Katy, TX (US); and Gustav Olov Skärgård, Oslo (NO)
Assigned to Enhanced Drilling AS, Straume (NO)
Filed by Enhanced Drilling AS, Straume (NO)
Filed on Oct. 19, 2023, as Appl. No. 18/381,981.
Application 18/381,981 is a continuation of application No. 17/770,510, granted, now 11,891,861, previously published as PCT/NO2020/050266, filed on Oct. 30, 2020.
Claims priority of application No. 20191299 (NO), filed on Oct. 30, 2019.
Prior Publication US 2024/0044216 A1, Feb. 8, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. E21B 17/01 (2006.01); E21B 21/00 (2006.01); E21B 21/08 (2006.01)
CPC E21B 17/01 (2013.01) [E21B 21/001 (2013.01); E21B 21/082 (2020.05)] 47 Claims
OG exemplary drawing
 
1. A method of operating a drilling system in an open mode and a closed mode, respectively, the method comprising:
providing a riser having a return outlet to be coupled to a return pump, the return pump being adapted to pump fluid from the riser to above a surface of a body of water through a return line;
positioning a sealing element in the riser above the return outlet;
providing a by-pass functionality through the sealing element, wherein the sealing element design allows for opening up to allow flow therethrough;
arranging a choke downstream of the pump;
operating in the closed mode where the sealing element is essentially closed to prevent flow therethrough;
adjusting at least one of the choke and a pumping speed of the pump to regulate a pressure in the riser below the sealing element; and
switching between the open mode and the closed mode by opening and closing, respectively, the sealing element.