E21B 31/03
Freeing by flushing
E21B31/03 (Freeing by flushing) appears on 70 US grants and 51 published applications in this corpus.
Search patents in E21B- Granted patents
- 70
- Published applications
- 51
- Assignees
- 35
- Inventors
- 140
- Latest grant
- 1 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 2 | 0 |
| 1981 | 4 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 1 | 0 |
| 1985 | 1 | 0 |
| 1986 | 3 | 0 |
| 1987 | 1 | 0 |
| 1988 | 1 | 0 |
| 1989 | 4 | 0 |
| 1990 | 1 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 0 | 0 |
| 1995 | 1 | 0 |
| 1996 | 2 | 0 |
| 1997 | 1 | 0 |
| 1998 | 2 | 0 |
| 1999 | 2 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 2 |
| 2002 | 0 | 0 |
| 2003 | 0 | 1 |
| 2004 | 1 | 1 |
| 2005 | 1 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 1 |
| 2008 | 0 | 0 |
| 2009 | 0 | 1 |
| 2010 | 0 | 1 |
| 2011 | 0 | 0 |
| 2012 | 0 | 2 |
| 2013 | 1 | 4 |
| 2014 | 0 | 0 |
| 2015 | 3 | 1 |
| 2016 | 2 | 0 |
| 2017 | 1 | 1 |
| 2018 | 0 | 0 |
| 2019 | 0 | 3 |
| 2020 | 3 | 9 |
| 2021 | 8 | 4 |
| 2022 | 2 | 5 |
| 2023 | 7 | 4 |
| 2024 | 3 | 6 |
| 2025 | 6 | 3 |
| 2026 | 1 | 2 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Logging tool1 Sep 2026US 12,723,484 B2Saudi Arabian Oil Company
- Visualization of fish while fishing in a wellbore18 Nov 2025US 12,473,791 B2Halliburton Energy Services.Inc.
- In or relating to well abandonment and slot recovery24 Jun 2025US 12,338,701 B2Ardyne Holdings Limited
- Fluid injection system and related methods27 May 2025US 12,312,892 B2Horisont Energi AS
- Methods for installing risers in a fluid injection system27 May 2025US 12,312,893 B2Horisont Energi AS
- Formation fluid sampling tools and processes for using same6 Aug 2026US 2026/0226829 A1Schlumberger Technology Corporation
- Logging tool29 Jan 2026US 2026/0028889 A1Saudi Arabian Oil Company
- Apparatus To Move An Object In An Open Hole Section of A Wellbore20 Nov 2025US 2025/0354448 A1Ardyne Holdings Limited
- Method for Casing Recovery18 Sep 2025US 2025/0290380 A1
- Methods and Apparatus for Casing Recovery17 Jul 2025US 2025/0230723 A1Ardyne Holdings Limited
Most cited
By later US patents
- Downhole valve for oil/gas well187US 5,499,687 A1996
- Downhole valve for use when drilling an oil or gas well61US 4,889,199 A1989
- Methods of drilling well boreholes and compositions used therein61US 5,260,268 AThe Lubrizol Corporation · 1993
- Use of mono and polyalkylene glycol ethers as agents for the release of differentially stuck drill pipe41US 4,614,235 AExxon Chemical Patents Inc. · 1986
- Tool for recovering junk and debris from a wellbore of a well39US 8,453,724 B2Saudi Arabian Oil Company · 2013