E21B 33/1291
Anchor set by wedge or cam in combination with frictional effect, using
Official title: {anchor set by wedge or cam in combination with frictional effect, using so-called drag-blocks (E21B33/1295 takes precedence)}
E21B33/1291 (Anchor set by wedge or cam in combination with frictional effect, using) appears on 358 US grants and 324 published applications in this corpus.
Search patents in E21B- Granted patents
- 358
- Published applications
- 324
- Assignees
- 125
- Inventors
- 577
- Latest grant
- 1 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 3 | 0 |
| 1978 | 2 | 0 |
| 1979 | 2 | 0 |
| 1980 | 0 | 0 |
| 1981 | 2 | 0 |
| 1982 | 1 | 0 |
| 1983 | 4 | 0 |
| 1984 | 3 | 0 |
| 1985 | 6 | 0 |
| 1986 | 10 | 0 |
| 1987 | 11 | 0 |
| 1988 | 2 | 0 |
| 1989 | 6 | 0 |
| 1990 | 7 | 0 |
| 1991 | 9 | 0 |
| 1992 | 6 | 0 |
| 1993 | 6 | 0 |
| 1994 | 7 | 0 |
| 1995 | 0 | 0 |
| 1996 | 1 | 0 |
| 1997 | 2 | 0 |
| 1998 | 1 | 0 |
| 1999 | 0 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 3 | 2 |
| 2003 | 0 | 0 |
| 2004 | 0 | 1 |
| 2005 | 1 | 2 |
| 2006 | 0 | 3 |
| 2007 | 1 | 0 |
| 2008 | 1 | 1 |
| 2009 | 2 | 2 |
| 2010 | 0 | 1 |
| 2011 | 1 | 2 |
| 2012 | 0 | 5 |
| 2013 | 1 | 15 |
| 2014 | 6 | 15 |
| 2015 | 18 | 32 |
| 2016 | 12 | 26 |
| 2017 | 27 | 25 |
| 2018 | 25 | 38 |
| 2019 | 23 | 18 |
| 2020 | 24 | 21 |
| 2021 | 18 | 30 |
| 2022 | 25 | 33 |
| 2023 | 28 | 17 |
| 2024 | 23 | 16 |
| 2025 | 23 | 14 |
| 2026 | 4 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Compact downhole tool1 Sep 2026US 12,723,485 B2Nine Downhole Technologies, LLC
- Plugging assemblies for plugging cased wellbores11 Aug 2026US 12,704,036 B2G&H Diversified Manufacturing LP
- Compact downhole tool31 Mar 2026US 12,590,505 B2Nine Downhole Technologies, LLC
- Compact downhole tool6 Jan 2026US 12,516,585 B2Nine Downhole Technologies, LLC
- Expandable metal slip ring for use with a sealing assembly30 Dec 2025US 12,509,958 B2Halliburton Energy Services.Inc.
- Plugging assemblies for plugging cased wellbores1 Oct 2026US 2026/0298044 A1G&H Diversified Manufacturing LP
- Expandable metal slip ring for use with a sealing assembly21 May 2026US 2026/0139565 A1Halliburton Energy Services.Inc.
- Downhole tool and setting system for use in a wellbore7 May 2026US 2026/0125964 A1The WellBoss Company, LLC
- Sealing on service packers30 Apr 2026US 2026/0117614 A1Expro North Sea Limited
- Systems and methods for producing a housingless tubing anchor catcher26 Feb 2026US 2026/0055678 A1Tech Tac Company, Inc.
Most cited
By later US patents
- Retrievable straddle packer171US 4,590,995 AHalliburton Company · 1986
- Drillable, testing, treat, squeeze packer140US 4,834,184 AHalliburton Company · 1989
- Retrievable bridge plug and retrieving tool139US 5,813,456 A1998
- Variable outside diameter tool for use in pikewells135US 4,842,082 ASmith International (North Sea) Limited · 1989
- Well tool having a metal seal and bi-directional lock123US 4,588,030 ACamco, Incorporated · 1986