- All sections
- C - Chemistrymetallurgy
- C21D - Modifying the physical structure of ferrous metalsgeneral devices for heat treatment of ferrous or non-ferrous metals or alloysmaking metal malleable, e.g. by decarburisation or tempering
- C21D 9/04 - Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articlesFurnaces therefor for rails
Patent holdings for IPC class C21D 9/04
Total number of patents in this class: 235
10-year publication summary
|
16
|
12
|
20
|
21
|
21
|
11
|
13
|
10
|
17
|
8
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| JFE Steel Corporation | 6833 |
54 |
| Nippon Steel Corporation | 6231 |
28 |
| Pangang Group Panzhihua Iron & Steel Research Institute Co., Ltd. | 71 |
21 |
| ArcelorMittal | 2280 |
13 |
| Voestalpine Schienen GmbH | 14 |
11 |
| Nippon Steel & Sumitomo Metal Corporation | 1988 |
9 |
| Danieli & C. Officine Meccaniche S.p.A. | 715 |
8 |
| Pangang Group Panzhihua Steel & Vanadium Co., Ltd. | 11 |
8 |
| ArcelorMittal Investigacion y Desarrollo SL | 209 |
7 |
| Wuhan Iron and Steel Company Limited | 28 |
5 |
| Dai-Ichi High Frequency Co., Ltd. | 34 |
4 |
| EVRAZ Inc. NA Canada | 4 |
4 |
| Caterpillar Inc. | 9540 |
3 |
| Huazhong University of Science and Technology | 1047 |
3 |
| Matisa Materiel Industriel SA | 75 |
3 |
| Pangang Group Research Institute Co., Ltd. | 22 |
3 |
| Primetals Technologies Italy S.r.l. | 14 |
3 |
| VAE Eisenbahnsysteme GmbH | 10 |
3 |
| VAE GmbH | 19 |
3 |
| Wuhan Nrd Laser Engineering Co., Ltd | 8 |
3 |
| Other owners | 39 |