US 12,264,557 B2
Reverse circulator and method
Jason Burke, Houston, TX (US); John G. Eller, Houston, TX (US); and Matthew L. White, Houston, TX (US)
Assigned to ConocoPhillips Company, Houston, TX (US)
Filed by CONOCOPHILLIPS COMPANY, Houston, TX (US)
Filed on Aug. 22, 2022, as Appl. No. 17/821,287.
Claims priority of provisional application 63/242,239, filed on Sep. 9, 2021.
Prior Publication US 2023/0078999 A1, Mar. 16, 2023
Int. Cl. E21B 34/14 (2006.01)
CPC E21B 34/14 (2013.01) [E21B 2200/06 (2020.05)] 3 Claims
OG exemplary drawing
 
1. A method of reverse circulating in a well, said method comprising:
a) providing a drillstring with a reverse circulator above a bottom hole assembly, said reverse circulator, comprising:
i) an inner pipe having a first tool joint at a first end,
ii) an outer pipe having a second tool joint at a second end,
iii) two or more holes in one of said inner pipe or said outer pipe,
iv) said outer pipe assembled around said inner pipe to form a nested pipe assembly such that said first and second tool joints are at a first and second end of said nested pipe assembly, said first end opposite said second end, and said inner pipe is slidingly fitted at least partially inside said outer pipe and thereby reversibly blocking said two or more holes;
b) forward pumping fluid down said drillstring with weight on said drillstring until reverse circulation is desired;
c) ceasing said forward pumping;
d) lifting said drillstring until said inner pipe and said outer pipe partially separate exposing said two or more holes;
e) reverse pumping fluid down an annulus outside said drillstring without weight on said drillstring until forward circulation is desired;
f) ceasing said reverse pumping; and
g) repeating step b) or steps b-f) one or more times.