E21B 21/10
Valve arrangements in drilling-fluid circulation systems
E21B21/10 (Valve arrangements in drilling-fluid circulation systems) appears on 1,989 US grants and 1,668 published applications in this corpus.
Search patents in E21B- Granted patents
- 1,989
- Published applications
- 1,668
- Assignees
- 631
- Inventors
- 2,762
- Latest grant
- 8 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 18 | 0 |
| 1977 | 12 | 0 |
| 1978 | 19 | 0 |
| 1979 | 5 | 0 |
| 1980 | 4 | 0 |
| 1981 | 37 | 0 |
| 1982 | 20 | 0 |
| 1983 | 21 | 0 |
| 1984 | 26 | 0 |
| 1985 | 11 | 0 |
| 1986 | 25 | 0 |
| 1987 | 21 | 0 |
| 1988 | 10 | 0 |
| 1989 | 22 | 0 |
| 1990 | 17 | 0 |
| 1991 | 19 | 0 |
| 1992 | 13 | 0 |
| 1993 | 13 | 0 |
| 1994 | 9 | 0 |
| 1995 | 13 | 0 |
| 1996 | 18 | 0 |
| 1997 | 10 | 0 |
| 1998 | 28 | 0 |
| 1999 | 26 | 0 |
| 2000 | 31 | 0 |
| 2001 | 47 | 16 |
| 2002 | 34 | 29 |
| 2003 | 35 | 34 |
| 2004 | 40 | 63 |
| 2005 | 21 | 31 |
| 2006 | 50 | 59 |
| 2007 | 35 | 58 |
| 2008 | 45 | 58 |
| 2009 | 35 | 54 |
| 2010 | 43 | 57 |
| 2011 | 42 | 63 |
| 2012 | 40 | 83 |
| 2013 | 53 | 93 |
| 2014 | 77 | 84 |
| 2015 | 68 | 105 |
| 2016 | 94 | 90 |
| 2017 | 68 | 91 |
| 2018 | 90 | 110 |
| 2019 | 99 | 77 |
| 2020 | 111 | 108 |
| 2021 | 94 | 74 |
| 2022 | 92 | 67 |
| 2023 | 79 | 53 |
| 2024 | 64 | 45 |
| 2025 | 56 | 39 |
| 2026 | 29 | 27 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Method and apparatus for automatic drill out8 Sep 2026US 12,729,591 B2Tetra Technologies, Inc.
- Valve cartridge8 Sep 2026US 12,729,593 B2SPM Oil & Gas Inc.
- Desander assembly for plunger lift system25 Aug 2026US 12,716,343 B2
- Stall detection and recovery for mud motors25 Aug 2026US 12,716,348 B2Helmerich & Payne, Inc.
- Fasteners for an underwater drilling assembly18 Aug 2026US 12,709,366 B2Resolve Marine Group, Inc.
- Civil engineering machine and method for forming a hole10 Sep 2026US 2026/0266018 A1BAUER Offshore Technologies GmbH
- Intelligent traction systems and control methods thereof10 Sep 2026US 2026/0266170 A1Chengdu University of Technology
- Advancing a tubular string in a wellbore3 Sep 2026US 2026/0258707 A1
- An extensible tubing and a method of facilitating transfer of fluid27 Aug 2026US 2026/0251026 A1MH Tech AS
- On demand flow pulsing system20 Aug 2026US 2026/0243134 A1National Oilwell Varco, L. P.
Most cited
By later US patents
- Downhole surge pressure reduction system and method of use340US 5,960,881 AJerry P. Allamon · 1999
- Steerable rotary drilling systems259US 5,706,905 ACamco Drilling Group Limited of Hycalog · 1998
- Method and apparatus for installing a cementing float shoe on the bottom of a well casing217US 4,413,682 ABaker Oil Tools, Inc. · 1983
- Circulation tool193US 6,253,861 B1Specialised Petroleum Services Limited · 2001
- Method and apparatus for downhole fluid blast cleaning of oil well casing191US 5,797,454 ASonoma Corporation · 1998