DIFF Subgroup
B21D 51/24 high-pressure containers, e.g. boilers, bottles
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Making hollow objects > characterised by the use of the objects > high-pressure containers, e.g. boilers, bottles
CPC:
Making hollow objects (from thick-walled or non uniform tubes B21K21/00) > characterised by the use of the objects (making heat exchangers B21D53/02) > high-pressure containers, e.g. boilers, bottles
No child classifications to compare. This is a leaf node in both IPC and CPC.
Top Applicants
Top Applicants (IPC)
Class B21,2013–2023, worldwide · Source: EPO PATSTAT
- JFE STEEL 2,318
- JFE STEEL JP 2,294
- POSCO (POHANG IRON AND STEEL COMPANY) KR 2,083
- NIPPON STEEL CORPORATION JP 1,650
- NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 1,631
- SMS GROUP DE 1,472
- BAOSHAN IRON & STEEL COMPANY 1,181
- SGCC(STATE GRID CORPORATION OF CHINA) 1,079
- ANHUI JIANGHUAI AUTOMOBILE 984
- HYUNDAI STEEL COMPANY KR 980
Top Applicants (CPC)
Class B21,2013–2023, worldwide · Source: EPO PATSTAT
- JFE STEEL JP 2,667
- NIPPON STEEL CORPORATION JP 2,049
- POSCO (POHANG IRON AND STEEL COMPANY) KR 1,967
- NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 1,800
- SMS GROUP DE 1,538
- JFE STEEL 1,150
- ARCELORMITTAL LU 1,142
- BAOSHAN IRON & STEEL COMPANY 821
- HYUNDAI STEEL COMPANY KR 808
- THYSSENKRUPP STEEL EUROPE DE 660