- 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: 268
10-year publication summary
|
12
|
20
|
21
|
21
|
11
|
13
|
10
|
18
|
17
|
14
|
| 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 | 2026 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| JFE Steel Corporation | 7574 |
58 |
| Nippon Steel Corporation | 6919 |
34 |
| Pangang Group Panzhihua Iron & Steel Research Institute Co., Ltd. | 84 |
26 |
| ArcelorMittal | 2695 |
16 |
| Pangang Group Panzhihua Steel & Vanadium Co., Ltd. | 16 |
11 |
| Voestalpine Schienen GmbH | 14 |
11 |
| Nippon Steel & Sumitomo Metal Corporation | 1981 |
9 |
| Danieli & C. Officine Meccaniche S.p.A. | 720 |
8 |
| ArcelorMittal Investigacion y Desarrollo SL | 208 |
7 |
| Wuhan Iron and Steel Company Limited | 34 |
6 |
| Dai-Ichi High Frequency Co., Ltd. | 37 |
4 |
| Chengdu Advanced Metal Materials Industry Technology Research Institute Co., Ltd. | 21 |
4 |
| Caterpillar Inc. | 10284 |
3 |
| EVRAZ Inc. NA Canada | 3 |
3 |
| Huazhong University of Science and Technology | 1132 |
3 |
| Matisa Materiel Industriel SA | 74 |
3 |
| Pangang Group Research Institute Co., Ltd. | 25 |
3 |
| Pellerin Milnor Corporation | 59 |
3 |
| Primetals Technologies Italy S.r.l. | 14 |
3 |
| VAE Eisenbahnsysteme GmbH | 8 |
3 |
| Other owners | 50 |