E21D 20/02
Setting anchoring-bolts: with provisions for grouting
Official title: with provisions for grouting
E21D20/02 (Setting anchoring-bolts: with provisions for grouting) appears on 424 US grants and 250 published applications in this corpus.
Search patents in E21D- Granted patents
- 424
- Published applications
- 250
- Assignees
- 214
- Inventors
- 771
- Latest grant
- 18 Aug 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 6 | 0 |
| 1977 | 8 | 0 |
| 1978 | 10 | 0 |
| 1979 | 14 | 0 |
| 1980 | 13 | 0 |
| 1981 | 19 | 0 |
| 1982 | 17 | 0 |
| 1983 | 11 | 0 |
| 1984 | 7 | 0 |
| 1985 | 21 | 0 |
| 1986 | 6 | 0 |
| 1987 | 17 | 0 |
| 1988 | 11 | 0 |
| 1989 | 9 | 0 |
| 1990 | 5 | 0 |
| 1991 | 11 | 0 |
| 1992 | 5 | 0 |
| 1993 | 7 | 0 |
| 1994 | 5 | 0 |
| 1995 | 3 | 0 |
| 1996 | 7 | 0 |
| 1997 | 4 | 0 |
| 1998 | 3 | 0 |
| 1999 | 5 | 0 |
| 2000 | 5 | 0 |
| 2001 | 4 | 3 |
| 2002 | 10 | 2 |
| 2003 | 4 | 7 |
| 2004 | 5 | 4 |
| 2005 | 2 | 7 |
| 2006 | 8 | 7 |
| 2007 | 2 | 7 |
| 2008 | 4 | 6 |
| 2009 | 5 | 11 |
| 2010 | 7 | 10 |
| 2011 | 3 | 11 |
| 2012 | 6 | 18 |
| 2013 | 7 | 9 |
| 2014 | 10 | 10 |
| 2015 | 10 | 14 |
| 2016 | 8 | 6 |
| 2017 | 7 | 11 |
| 2018 | 7 | 13 |
| 2019 | 17 | 11 |
| 2020 | 12 | 17 |
| 2021 | 11 | 16 |
| 2022 | 13 | 8 |
| 2023 | 6 | 15 |
| 2024 | 7 | 12 |
| 2025 | 14 | 10 |
| 2026 | 6 | 5 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Drilling and bolting tool18 Aug 2026US 12,709,981 B2Joy Global Underground Mining LLC
- Tunnel constraint anchor cable and method for improving stability of initial support structure14 Jul 2026US 12,680,451 B2Chang An University
- Active control method and device for large deformation of deep thin-bedded surrounding rock9 Jun 2026US 12,650,076 B2Huaneng Lancang River Hydropower Inc.
- Bolter2 Jun 2026US 12,644,385 B2Joy Global Underground Mining LLC
- Static crushing directional anchor withdrawal method at end of large-mining-height working face21 Apr 2026US 12,607,121 B2Huating Coal Group Co., Ltd.
- Bolter24 Sep 2026US 2026/0286845 A1Joy Global Underground Mining LLC
- Drill Head Injection System for a Self-Drilling Rock Bolt Assembly10 Sep 2026US 2026/0266179 A1Oka Rock Bolt Technologies Pty Limited
- Sealing device for positioning points in holes of process grouting28 May 2026US 2026/0146535 A1Anhui University of Science and Technology
- Rock bolting rig and method for rock reinforcing14 May 2026US 2026/0132718 A1Sandvik Mining and Construction Oy
- Bolting rig and method for rock reinforcing14 May 2026US 2026/0132719 A1Sandvik Mining and Construction Oy
Most cited
By later US patents
- Organic grouting composition for anchoring a bolt in a hole60US 4,280,943 AE. I. Du Pont de Nemours and Company · 1981
- Squirt cartridge for mixing and dispensing a two-component mass56US 4,676,406 AUpat GmbH & Co. · 1987
- Post tensionable grouted anchor assembly53US 4,295,761 AStratabolt Corporation · 1981
- Automatic roof bolting system for mines43US 4,229,124 AJoy Manufacturing Company · 1980
- Resin reinforced expansion anchor system42US 4,764,055 ABirmingham Bolt Company · 1988