C21C 2007/0093
Duplex process
Official title: {Duplex process; Two stage processes}
C21C2007/0093 (Duplex process) appears on 38 US grants and 12 published applications in this corpus.
Search patents in C21C- Granted patents
- 38
- Published applications
- 12
- Assignees
- 34
- Inventors
- 128
- Latest grant
- 21 Apr 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1977 | 1 | 0 |
| 1978 | 0 | 0 |
| 1979 | 0 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 3 | 0 |
| 1986 | 2 | 0 |
| 1987 | 1 | 0 |
| 1988 | 3 | 0 |
| 1989 | 3 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 1 | 0 |
| 1993 | 1 | 0 |
| 1994 | 2 | 0 |
| 1995 | 3 | 0 |
| 1996 | 3 | 0 |
| 1997 | 0 | 0 |
| 1998 | 2 | 0 |
| 1999 | 2 | 0 |
| 2000 | 1 | 0 |
| 2001 | 0 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 1 |
| 2004 | 1 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 0 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 0 | 0 |
| 2013 | 0 | 0 |
| 2014 | 0 | 1 |
| 2015 | 0 | 0 |
| 2016 | 0 | 0 |
| 2017 | 0 | 1 |
| 2018 | 0 | 1 |
| 2019 | 1 | 0 |
| 2020 | 1 | 1 |
| 2021 | 1 | 0 |
| 2022 | 0 | 1 |
| 2023 | 1 | 3 |
| 2024 | 1 | 0 |
| 2025 | 2 | 3 |
| 2026 | 1 | 0 |
By publication year. Applications have been published since 2001. 2026 runs to 8 Oct.
Recent patents
- Ultra-high phosphorus molten iron low-cost smelting method for polar steel21 Apr 2026US 12,606,877 B2Laiwu Steel Yinshan Section Co., Ltd.
- Process for producing clean steel products with a low nitrogen content using an electric arc furnace and a degassing system13 May 2025US 12,296,379 B2Ternium México, S.A. de C.V.
- Degassing method for manufacturing steel18 Feb 2025US 12,227,813 B2United States Steel Corporation
- Degassing method for manufacturing ultra-low carbon, nitrogen, sulfur steel17 Dec 2024US 12,168,808 B2United States Steel Corporation
- Method for producing high nitrogen steel by duplex melting process of pressurized ladle refining and pressurized electroslag remelting22 Aug 2023US 11,732,337 B2Northeastern University
- Degassing method for manufacturing steel12 Jun 2025US 2025/0188555 A1United States Steel Corporation
- Process for producing clean steel with a low nitrogen content using an electric arc furnace and a degassing system13 Mar 2025US 2025/0083218 A1Ternium México, S.A. de C.V.
- Degassing method for manufacturing ultra-low carbon, nitrogen, sulfur steel6 Feb 2025US 2025/0043372 A1United States Steel Corporation
- Degassing method for manufacturing steel12 Oct 2023US 2023/0323492 A1United States Steel Corporation
- Ultra-high phosphorus molten iron low-cost smelting method for polar steel13 Jul 2023US 2023/0220504 A1Laiwu Steel Yinshan Section Co., Ltd.
Most cited
By later US patents
- Vertical shaft melting furnace and method of melting65US 4,877,449 AInstitute of Gas Technology · 1989
- Method for producing iron25US 4,861,368 AKloeckner CRA Technologie GmbH · 1989
- Reactor for iron making24US 4,790,516 ADaido Tokushuko Kabushiki Kaisha · 1988
- Charging material preheater for preheating charging material for a metallurgical smelting unit13US 4,852,858 AKortec, Inc. · 1989
- Method for producing steel8US 5,286,277 AZaptech Corporation · 1994