E21B 36/04
Heating, cooling or insulating arrangements for boreholes or wells: using electrical heaters
Official title: using electrical heaters
E21B36/04 (Heating, cooling or insulating arrangements for boreholes or wells: using electrical heaters) appears on 748 US grants and 664 published applications in this corpus.
Search patents in E21B- Granted patents
- 748
- Published applications
- 664
- Assignees
- 190
- Inventors
- 1,060
- Latest grant
- 16 Jun 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 0 | 0 |
| 1978 | 1 | 0 |
| 1979 | 4 | 0 |
| 1980 | 2 | 0 |
| 1981 | 5 | 0 |
| 1982 | 5 | 0 |
| 1983 | 11 | 0 |
| 1984 | 8 | 0 |
| 1985 | 14 | 0 |
| 1986 | 13 | 0 |
| 1987 | 12 | 0 |
| 1988 | 9 | 0 |
| 1989 | 7 | 0 |
| 1990 | 9 | 0 |
| 1991 | 9 | 0 |
| 1992 | 9 | 0 |
| 1993 | 9 | 0 |
| 1994 | 10 | 0 |
| 1995 | 5 | 0 |
| 1996 | 5 | 0 |
| 1997 | 5 | 0 |
| 1998 | 6 | 0 |
| 1999 | 5 | 0 |
| 2000 | 6 | 0 |
| 2001 | 8 | 0 |
| 2002 | 7 | 80 |
| 2003 | 15 | 34 |
| 2004 | 53 | 18 |
| 2005 | 23 | 29 |
| 2006 | 28 | 8 |
| 2007 | 11 | 25 |
| 2008 | 16 | 39 |
| 2009 | 25 | 52 |
| 2010 | 31 | 17 |
| 2011 | 20 | 19 |
| 2012 | 33 | 21 |
| 2013 | 26 | 26 |
| 2014 | 22 | 32 |
| 2015 | 27 | 36 |
| 2016 | 22 | 24 |
| 2017 | 20 | 26 |
| 2018 | 22 | 20 |
| 2019 | 30 | 19 |
| 2020 | 13 | 26 |
| 2021 | 29 | 25 |
| 2022 | 20 | 17 |
| 2023 | 21 | 25 |
| 2024 | 25 | 23 |
| 2025 | 18 | 16 |
| 2026 | 13 | 7 |
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
- Subsea induction heating system and related method16 Jun 2026US 12,655,720 B2
- Extraction from a formation with induction heating16 Jun 2026US 12,655,732 B2Joslyn Energy Development Incorporated
- Method and system for oil recovery using solvent-assisted electric heating16 Jun 2026US 12,655,733 B2
- Efficient surface and downhole heating of injected carbon dioxide7 Apr 2026US 12,595,719 B2Schlumberger Technology Corporation
- Integrated system for viscosity reduction in heavy oil wells with artificial lift through controlled heating using variable frequency drives10 Sep 2026US 2026/0266162 A1Magneta, LLC
- Method and apparatus for thermal assisted oil-water separation and energy recovery in oil production wells6 Aug 2026US 2026/0226819 A1Saudi Arabian Oil Company
- Downhole tool employing a radioisotope heater unit or radioisotope generator to increase or decrease a rate of reaction of a hydrolysis of an expandable metal9 Jul 2026US 2026/0193961 A1Halliburton Energy Services.Inc.
- Method, system, device, and medium for calculating temperature distribution in in-situ electrical heating of reservoir18 Jun 2026US 2026/0169185 A1Southwest Petroleum University
- Systems and methods for converting biomass to biocrude using hydrothermal liquefaction14 May 2026US 2026/0132340 A1Enoverra Energy & Environment Inc
Most cited
By later US patents
- In-situ tuned microwave oil extraction process483US 5,082,054 A1992
- Method for in situ heat processing of hydrocarbonaceous formations474US 4,140,180 AIIT Research Institute · 1979
- Apparatus and method for in situ heat processing of hydrocarbonaceous formations456US 4,144,935 AIIT Research Institute · 1979
- Self-regulating heater utilizing ferrite-type body449US 5,182,427 AMetcal, Inc. · 1993
- Balanced-line RF electrode system for use in RF ground heating to recover oil from oil shale443US 5,236,039 AGeneral Electric Company · 1993