E21B 33/16
Using plugs for isolating cement charge
Official title: using plugs for isolating cement charge; Plugs therefor {(stage cementing E21B33/146; spacer compositions C09K8/424)}
E21B33/16 (Using plugs for isolating cement charge) appears on 665 US grants and 524 published applications in this corpus.
Search patents in E21B- Granted patents
- 665
- Published applications
- 524
- Assignees
- 143
- Inventors
- 883
- Latest grant
- 6 Oct 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 3 | 0 |
| 1977 | 3 | 0 |
| 1978 | 1 | 0 |
| 1979 | 4 | 0 |
| 1980 | 3 | 0 |
| 1981 | 2 | 0 |
| 1982 | 5 | 0 |
| 1983 | 6 | 0 |
| 1984 | 7 | 0 |
| 1985 | 2 | 0 |
| 1986 | 3 | 0 |
| 1987 | 8 | 0 |
| 1988 | 4 | 0 |
| 1989 | 9 | 0 |
| 1990 | 7 | 0 |
| 1991 | 8 | 0 |
| 1992 | 9 | 0 |
| 1993 | 7 | 0 |
| 1994 | 9 | 0 |
| 1995 | 9 | 0 |
| 1996 | 10 | 0 |
| 1997 | 6 | 0 |
| 1998 | 13 | 0 |
| 1999 | 10 | 0 |
| 2000 | 4 | 0 |
| 2001 | 8 | 2 |
| 2002 | 15 | 28 |
| 2003 | 17 | 15 |
| 2004 | 22 | 34 |
| 2005 | 16 | 18 |
| 2006 | 22 | 8 |
| 2007 | 20 | 8 |
| 2008 | 5 | 15 |
| 2009 | 9 | 7 |
| 2010 | 8 | 10 |
| 2011 | 5 | 11 |
| 2012 | 13 | 11 |
| 2013 | 6 | 13 |
| 2014 | 8 | 20 |
| 2015 | 14 | 25 |
| 2016 | 18 | 22 |
| 2017 | 19 | 21 |
| 2018 | 23 | 34 |
| 2019 | 37 | 19 |
| 2020 | 26 | 26 |
| 2021 | 31 | 38 |
| 2022 | 34 | 34 |
| 2023 | 37 | 36 |
| 2024 | 49 | 37 |
| 2025 | 33 | 21 |
| 2026 | 18 | 11 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Systems and methods of deploying a wiper plug in a downhole tubular string6 Oct 2026US 12,753,670 B1Halliburton Energy Services.Inc.
- Sub-surface release plug with pressure bypass25 Aug 2026US 12,716,323 B2Weatherford Technology Holdings, LLC
- Composition including cured geopolymer particles, and methods of making and using thereof4 Aug 2026US 12,698,432 B2Halliburton Energy Services.Inc.
- Methods for determining a position of a droppable object in a wellbore4 Aug 2026US 12,698,708 B2Schlumberger Technology Corporation
- Shoe track assembly system and method of use28 Jul 2026US 12,692,783 B1Citadel Casing Solutions LLC
- Method and tool for cementing wellbore13 Aug 2026US 2026/0235012 A1Baker Hughes Oilfield Operations LLC
- Droppable object with locating system and pressure pulse telemetry actuator for use in a wellbore6 Aug 2026US 2026/0226823 A1Schlumberger Technology Corporation
- Assembly for use in abandoning a wellbore9 Jul 2026US 2026/0193955 A1
- Combination landing and float collar2 Jul 2026US 2026/0185422 A1Downhole Products Limited
- Sub-surface release plug with pressure bypass18 Jun 2026US 2026/0168349 A1Weatherford Technology Holdings, LLC
Most cited
By later US patents
- Downhole surge pressure reduction system and method of use340US 5,960,881 AJerry P. Allamon · 1999
- Procedures and equipment for profiling and jointing of pipes319US 6,457,532 B1Weatherford/Lamb, Inc. · 2002
- Method and apparatus for drilling and lining a wellbore236US 6,543,552 B1Weatherford/Lamb, Inc. · 2003
- Hydraulically actuated liner hanger arrangement and method215US 5,318,131 A1994
- Method for multi-lateral completion and cementing the juncture with lateral wellbores207US 5,526,880 ABaker Hughes Incorporated · 1996