- All sections
- E - Fixed constructions
- E21D - Shaftstunnelsgallerieslarge underground chambers
- E21D 1/12 - Preparation of the ground by freezing
Patent holdings for IPC class E21D 1/12
Total number of patents in this class: 8
10-year publication summary
|
1
|
1
|
1
|
0
|
1
|
0
|
1
|
0
|
0
|
0
|
| 2016 | 2017 | 2018 | 2019 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
Principal owners for this class
| Owner |
All patents
|
This class
|
|---|---|---|
| Chemical Grouting Co., Ltd. | 5 |
2 |
| China University of Mining and Technology | 1266 |
1 |
| Laurentian University of Sudbury | 13 |
1 |
| Linde Aktiengesellschaft | 1496 |
1 |
| China Coal Mine Engineering Co., Ltd. | 1 |
1 |
| China Coal Construction Group Co., Ltd | 1 |
1 |
| China Coal Tianjin Design Engineering Co, Ltd. | 1 |
1 |
| Other owners | 0 |