E21B 33/05
Cementing-heads
Official title: Cementing-heads, e.g. having provision for introducing cementing plugs
E21B33/05 (Cementing-heads) appears on 274 US grants and 225 published applications in this corpus.
Search patents in E21B- Granted patents
- 274
- Published applications
- 225
- Assignees
- 64
- Inventors
- 335
- Latest grant
- 16 Jun 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 2 | 0 |
| 1977 | 2 | 0 |
| 1978 | 0 | 0 |
| 1979 | 1 | 0 |
| 1980 | 0 | 0 |
| 1981 | 2 | 0 |
| 1982 | 2 | 0 |
| 1983 | 0 | 0 |
| 1984 | 3 | 0 |
| 1985 | 1 | 0 |
| 1986 | 4 | 0 |
| 1987 | 2 | 0 |
| 1988 | 3 | 0 |
| 1989 | 2 | 0 |
| 1990 | 3 | 0 |
| 1991 | 4 | 0 |
| 1992 | 2 | 0 |
| 1993 | 1 | 0 |
| 1994 | 1 | 0 |
| 1995 | 4 | 0 |
| 1996 | 1 | 0 |
| 1997 | 1 | 0 |
| 1998 | 5 | 0 |
| 1999 | 7 | 0 |
| 2000 | 2 | 0 |
| 2001 | 8 | 1 |
| 2002 | 3 | 4 |
| 2003 | 5 | 11 |
| 2004 | 7 | 4 |
| 2005 | 1 | 7 |
| 2006 | 7 | 8 |
| 2007 | 8 | 7 |
| 2008 | 5 | 15 |
| 2009 | 8 | 1 |
| 2010 | 11 | 13 |
| 2011 | 8 | 19 |
| 2012 | 13 | 11 |
| 2013 | 11 | 13 |
| 2014 | 19 | 14 |
| 2015 | 10 | 16 |
| 2016 | 10 | 10 |
| 2017 | 11 | 10 |
| 2018 | 11 | 10 |
| 2019 | 9 | 5 |
| 2020 | 11 | 9 |
| 2021 | 6 | 7 |
| 2022 | 5 | 6 |
| 2023 | 7 | 5 |
| 2024 | 11 | 9 |
| 2025 | 10 | 9 |
| 2026 | 4 | 1 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Meltable material to seal flow-by passageways16 Jun 2026US 12,655,714 B2Cameron International Corporation
- Systems and methods with seal elements shaped to efficiently cement casing and seal a hanger in a wellhead housing21 Apr 2026US 12,607,084 B2Cameron International Corporation
- Method and apparatus for dropping a pump down plug or ball27 Jan 2026US 12,534,975 B2Gulfstream Services, Inc.
- Cement head flow diverter for tethered cement plug deployment6 Jan 2026US 12,516,586 B2Halliburton Energy Services.Inc.
- Systems and methods for cementing casing and sealing a hanger in a wellhead housing18 Nov 2025US 12,473,792 B2Cameron International Corporation
- Systems and methods for cementing casing and sealing a hanger in a wellhead housing16 Jul 2026US 2026/0201768 A1Cameron International Corporation
- Well abandonment and severance of control lines13 Nov 2025US 2025/0347190 A1Halliburton Energy Services.Inc.
- Meltable material to seal flow-by passageways18 Sep 2025US 2025/0290385 A1Cameron International Corporation
- Systems and methods with seal elements shaped to efficiently cement casing and seal a hanger in a wellhead housing4 Sep 2025US 2025/0277421 A1Cameron International Corporation
- Cement head flow diverter for tethered cement plug deployment4 Sep 2025US 2025/0277425 A1Halliburton Energy Services.Inc.
Most cited
By later US patents
- Downhole surge pressure reduction system and method of use340US 5,960,881 AJerry P. Allamon · 1999
- Top drive casing system213US 6,536,520 B1Weatherford/Lamb, Inc. · 2003
- Remote control plug-dropping head162US 5,833,002 ABaker Hughes Incorporated · 1998
- Method and multi-purpose apparatus for dispensing and circulating fluid in wellbore casing160US 5,735,348 AFrank's International, LLC · 1998
- Plug injection method and apparatus156US 5,095,988 A1992