C21C 5/00
Manufacture of carbon-steel
Official title: Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel {or stainless steel}
C21C5/00 (Manufacture of carbon-steel) appears on 2,727 US grants and 1,522 published applications in this corpus.
Search patents in C21C- Granted patents
- 2,727
- Published applications
- 1,522
- Assignees
- 1,050
- Inventors
- 5,000
- Latest grant
- 22 Sep 2026
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 91 | 0 |
| 1977 | 87 | 0 |
| 1978 | 84 | 0 |
| 1979 | 45 | 0 |
| 1980 | 66 | 0 |
| 1981 | 70 | 0 |
| 1982 | 58 | 0 |
| 1983 | 87 | 0 |
| 1984 | 92 | 0 |
| 1985 | 75 | 0 |
| 1986 | 64 | 0 |
| 1987 | 78 | 0 |
| 1988 | 83 | 0 |
| 1989 | 53 | 0 |
| 1990 | 60 | 0 |
| 1991 | 57 | 0 |
| 1992 | 44 | 0 |
| 1993 | 49 | 0 |
| 1994 | 62 | 0 |
| 1995 | 51 | 0 |
| 1996 | 63 | 0 |
| 1997 | 33 | 0 |
| 1998 | 47 | 0 |
| 1999 | 62 | 0 |
| 2000 | 57 | 0 |
| 2001 | 55 | 17 |
| 2002 | 62 | 31 |
| 2003 | 49 | 52 |
| 2004 | 41 | 56 |
| 2005 | 24 | 37 |
| 2006 | 12 | 55 |
| 2007 | 20 | 59 |
| 2008 | 25 | 55 |
| 2009 | 36 | 64 |
| 2010 | 47 | 72 |
| 2011 | 53 | 83 |
| 2012 | 59 | 71 |
| 2013 | 55 | 57 |
| 2014 | 52 | 61 |
| 2015 | 39 | 61 |
| 2016 | 45 | 68 |
| 2017 | 51 | 50 |
| 2018 | 38 | 46 |
| 2019 | 47 | 38 |
| 2020 | 44 | 51 |
| 2021 | 31 | 60 |
| 2022 | 26 | 70 |
| 2023 | 43 | 69 |
| 2024 | 53 | 101 |
| 2025 | 53 | 75 |
| 2026 | 49 | 63 |
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
- High-carbon biogenic reagents and uses thereof1 Sep 2026US 12,723,211 B2Carbon Technology Holdings, LLC
- Blast furnace—converter steel production method based on carbon cycling28 Jul 2026US 12,692,561 B2Cisdi Engineering Co., Ltd
- Electric induction heating and melting furnace refractory life cycle wear imaging and processing28 Jul 2026US 12,692,564 B2Inductotherm Corp.
- Self-adaptive hanging structure of converter28 Jul 2026US 12,692,565 B2
- Tuyere for a metallurgical furnace1 Oct 2026US 2026/0297694 A1Paul Wurth S. A.
- Method for melting iron source1 Oct 2026US 2026/0297697 A1Nippon Steel Corporation
- Novel process for the smelting of a metalliferous feedstock material yielding reduced carbon emissions1 Oct 2026US 2026/0297698 A1Metix (Proprietary) Limited
- Production and preparation method of carburized gear shaft bars by means of converter process24 Sep 2026US 2026/0286458 A1Bengang Steel Plates Co., Ltd.
- Methods and systems for low-slag efficient smelting based on submerged supersonic gas-solid injection17 Sep 2026US 2026/0275436 A1University of Science and Technology Beijing
Most cited
By later US patents
- Probe for taking gas samples and heat measurements in a shaft furnace485US 5,108,192 APaul Wurth S. A. · 1992
- Apparatus and method for submerged injection of a feed composition into a molten metal bath151US 5,443,572 AMolten Metal Technology, Inc. · 1995
- Universal coupling117US 6,358,467 B1Metaullics Systems Co., L.P. · 2002
- Method for treating organic waste116US 5,537,940 AMolten Metal Technology, Inc. · 1996
- Method for top-charging solid waste into a molten metal bath115US 5,491,279 AMolten Metal Technology, Inc. · 1996