Method for heating steel sheet, method for producing coated steel sheet, direct fired furnace, and continuous hot-dip galvanizing facility
US-2025388989-A1 · Dec 25, 2025 · US
with flames
with flames · Cooperative Patent Classification (CPC)
Chemical and metallurgical processes, compounds, and materials.
Related technology areas
Mapped technology topics for this CPC code.
| Metric | Value |
|---|---|
| CPC code | C21D1/52 |
| Official title | with flames |
| Display label | with flames |
| Total patents | 64 |
Filing trend
Year-over-year patent counts classified under this CPC code.
Filing activity over the last five years is stable.
| Year | Patents |
|---|---|
| 2015 | 6 |
| 2016 | 6 |
| 2017 | 4 |
| 2018 | 11 |
| 2019 | 7 |
| 2020 | 5 |
| 2021 | 6 |
| 2022 | 7 |
| 2023 | 2 |
| 2024 | 3 |
| 2025 | 5 |
| 2026 | 2 |
Representative patents
Representative publications under this CPC code from precomputed stats, or recent filings when stats are unavailable.
Annealing method
US-12497678-B2 · Dec 16, 2025 · US
Hot-rolled steel sheet and method for manufacturing same
US-12428694-B2 · Sep 30, 2025 · US
Method for heating a furnace
US-2024263881-A1 · Aug 8, 2024 · US
Roll forming system with heat treatment and associated methods
US-2024024940-A1 · Jan 25, 2024 · US
Annealing method
US-2024026487-A1 · Jan 25, 2024 · US
Method of producing high-strength hot-dip galvanized steel sheet
US-2023082367-A1 · Mar 16, 2023 · US
Heating system for drill steel pipe billet and heating method thereof
US-11565294-B2 · Jan 31, 2023 · US
Hot-rolled steel sheet and method for manufacturing same
US-11492679-B2 · Nov 8, 2022 · US
Steel sheet temperature control device and temperature control method
US-11466340-B2 · Oct 11, 2022 · US
Production method of hot-dip galvanized steel sheet
US-11414736-B2 · Aug 16, 2022 · US
Method for the surface treatment of a steel Yankee
US-11414718-B2 · Aug 16, 2022 · US
Fast response heaters and associated control systems used in combination with metal treatment furnaces
US-11268765-B2 · Mar 8, 2022 · US
Method for manufacturing steel sheet for cold press and method for manufacturing press component
US-2022049324-A1 · Feb 17, 2022 · US
Hot-rolled steel sheet and method for manufacturing same
US-2022010396-A1 · Jan 13, 2022 · US
Hot-rolled steel sheet and method for manufacturing same
US-2021395852-A1 · Dec 23, 2021 · US
Large scale metal forming control system and method
US-11135632-B2 · Oct 5, 2021 · US
Heating system for drill steel pipe billet and heating method thereof
US-2021299723-A1 · Sep 30, 2021 · US
Steel sheet temperature control device and temperature control method
US-2021198765-A1 · Jul 1, 2021 · US
500 MPA yield strength-graded, high-stretchability hot-dip aluminum-zinc and color-coated steel plate and manufacturing method therefore
US-10982296-B2 · Apr 20, 2021 · US
Frequently asked questions
Answers are generated from the same data shown on this page.
- What is CPC C21D1/52?
- CPC C21D1/52 is the Cooperative Patent Classification code for “with flames.”
- How many patents are filed under CPC C21D1/52 (with flames)?
- Our database includes 64 publications tagged with this CPC code.
- Is patent activity under CPC C21D1/52 growing?
- Publication counts under this code: 3 in 2024 vs 5 in 2025 (latest complete years).