US 12,404,738 B2
Downhole pressure equalizer
Torgeir Rusten, Vikhammer (NO); and Gaute Sandvik, Saksvik (NO)
Assigned to INTERWELL P&A AS, Røyneberg (NO)
Appl. No. 18/281,016
Filed by Interwell P&A AS, Hafrsfjord (NO)
PCT Filed May 5, 2022, PCT No. PCT/EP2022/062176
§ 371(c)(1), (2) Date Sep. 8, 2023,
PCT Pub. No. WO2022/243056, PCT Pub. Date Nov. 24, 2022.
Claims priority of application No. 20210637 (NO), filed on May 21, 2021.
Prior Publication US 2024/0141753 A1, May 2, 2024
Int. Cl. E21B 33/13 (2006.01); E21B 23/04 (2006.01); E21B 29/02 (2006.01); E21B 36/00 (2006.01)
CPC E21B 33/13 (2013.01) [E21B 23/0412 (2020.05); E21B 23/0414 (2020.05); E21B 23/042 (2020.05); E21B 29/02 (2013.01); E21B 36/008 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A downhole pressure equalizer comprising:
an elongated housing comprising a piston compartment having a first end provided in fluid communication with an outside of the elongated housing and a second end provided in fluid communication with a process chamber of a well tool;
a piston device slidingly and sealingly engaged within the piston compartment, wherein the piston device separates the piston compartment into a first sub-compartment between the piston device and the first end and a second compartment between the piston device and the second end;
wherein the piston device comprises:
an outer piston section slidingly and sealingly engaged with the piston compartment, wherein the outer piston section comprises a sleeve having a through bore; and
an inner piston section slidingly and sealingly engaged within the through bore of the outer piston section,
wherein the downhole pressure equalizer is configured to be in one of:
a first state, in which a pressure difference between a fluid pressure in the first sub-compartment and a fluid pressure in the second sub-compartment causes the outer piston section and the inner piston section to move towards the second end of the piston compartment; and
a second state, in which the pressure difference between the fluid pressure in the first sub-compartment and the fluid pressure in the second sub-compartment causes the inner piston section to move towards the first end of the piston compartment while the outer piston section is kept stationary.