C21C 1/00
Refining of pig-iron
Official title: Refining of pig-iron; Cast iron
C21C1/00 (Refining of pig-iron) appears on 601 US grants and 274 published applications in this corpus.
Search patents in C21C- Granted patents
- 601
- Published applications
- 274
- Assignees
- 355
- Inventors
- 1,212
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 31 | 0 |
| 1977 | 21 | 0 |
| 1978 | 23 | 0 |
| 1979 | 19 | 0 |
| 1980 | 36 | 0 |
| 1981 | 21 | 0 |
| 1982 | 21 | 0 |
| 1983 | 30 | 0 |
| 1984 | 20 | 0 |
| 1985 | 24 | 0 |
| 1986 | 18 | 0 |
| 1987 | 19 | 0 |
| 1988 | 21 | 0 |
| 1989 | 16 | 0 |
| 1990 | 18 | 0 |
| 1991 | 6 | 0 |
| 1992 | 12 | 0 |
| 1993 | 10 | 0 |
| 1994 | 12 | 0 |
| 1995 | 5 | 0 |
| 1996 | 9 | 0 |
| 1997 | 5 | 0 |
| 1998 | 2 | 0 |
| 1999 | 7 | 0 |
| 2000 | 8 | 0 |
| 2001 | 10 | 4 |
| 2002 | 12 | 5 |
| 2003 | 8 | 6 |
| 2004 | 4 | 14 |
| 2005 | 7 | 9 |
| 2006 | 5 | 13 |
| 2007 | 3 | 6 |
| 2008 | 4 | 6 |
| 2009 | 5 | 5 |
| 2010 | 4 | 8 |
| 2011 | 2 | 10 |
| 2012 | 6 | 8 |
| 2013 | 7 | 10 |
| 2014 | 6 | 18 |
| 2015 | 6 | 15 |
| 2016 | 14 | 12 |
| 2017 | 14 | 14 |
| 2018 | 4 | 10 |
| 2019 | 6 | 10 |
| 2020 | 8 | 12 |
| 2021 | 5 | 9 |
| 2022 | 11 | 16 |
| 2023 | 8 | 12 |
| 2024 | 10 | 18 |
| 2025 | 11 | 9 |
| 2026 | 7 | 15 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Subgroups
Granted patents
Recent patents
- Direct current electric arc furnace22 Sep 2026US 12,742,218 B2Masercata Oy
- Converter steelmaking method23 Jun 2026US 12,662,712 B2Jfe Steel Corporation
- Method for manufacturing low-phosphorus molten steel9 Jun 2026US 12,649,955 B2Jfe Steel Corporation
- Process and system for the production of iron nuggets12 May 2026US 12,624,406 B2Carbontec Energy Corporation
- Production method for non-oriented silicon steel and non-oriented silicon steel31 Mar 2026US 12,590,351 B2Institute of Research of Iron and Steel, Jiangsu Province/Sha-Steel, Co. Ltd (Cn) China
- Method for manufacturing pig iron in a production line comprising an electrical smelting furnace10 Sep 2026US 2026/0265850 A1
- A method for manufacturing pig iron in a production line comprising an electrical smelting furnace3 Sep 2026US 2026/0258516 A1
- Molten iron dephosphorization method2 Jul 2026US 2026/0185173 A1Jfe Steel Corporation
- Method for producing metallic iron25 Jun 2026US 2026/0176707 A1Jef Steel Corporation
- Sulfur management in a smelting process21 May 2026US 2026/0139336 A1Nucor Corporation
Most cited
By later US patents
- Molten metal degassing device and impellers therefor121US 6,689,310 B12004
- Scrap melter and impeller113US 6,723,276 B12004
- Vortexer apparatus113US 7,497,988 B22009
- Gas mixing and dispersement in pumps for pumping molten metal109US 7,476,357 B22009
- Immersion and vaporization chamber107US 4,496,393 AGeorge Fischer Ltd. · 1985