IPC Subgroup
F22B 21/2 involving sectional or subdivided headers in separate arrangement for each water-tube set
Introduced: September 1968
Last revised: January 2006
Full Title
Water-tube boilers of vertical or steeply-inclined type, i.e. the water-tube sets being arranged vertically or substantially vertically > built-up from substantially-straight water tubes > involving sectional or subdivided headers in separate arrangement for each water-tube set
Classification Context
- Section:
- MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- Class:
- STEAM GENERATION
- Subclass:
- METHODS OF STEAM GENERATION; STEAM BOILERS
Top Applicants
Top 10 applicants by patent filingsfor class F22, 2013–2023, worldwide · Source: EPO PATSTAT
- XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY 922
- MIURA COMPANY 416
- HARBIN BOILER COMPANY 390
- MITSUBISHI HITACHI POWER SYSTEMS 303
- XIAN JIAOTONG UNIVERSITY 287
- SGCC(STATE GRID CORPORATION OF CHINA) 257
- HUADIAN ELECTRIC POWER RESEARCH INSTITUTE 253
- SIEMENS DE 247
- MIDEA 243
- NORTH CHINA ELECTRIC POWER UNIVERSITY 223