F22B 35/02 for steam boilers with natural convection circulation
Full Title
Control systems for steam boilers (for regulating feed-water supply F22D5/00; for controlling superheat temperature F22G5/00) > for steam boilers with natural convection circulation
Filing statistics
CPC F22B 35/02 belongs to the parent subclass F22B, which recorded 24,387 patent applications worldwide between 2013 and 2023. Annual filings grew from 1,821 in 2013 to 2,125 in 2023 (+17%), peaking at 2,634 applications in 2017. The most active applicants in class F22 are XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY (544 applications), SIEMENS (306 applications) and PHILIP MORRIS PRODUCTS (258 applications).
Source: EPO PATSTAT, worldwide filings
1 direct subcode
Child Classifications
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- F22B 35/04 during starting-up periods, i.e. during the periods between the lighting of the furnaces and the attainment of the normal operating temperature of the steam boilers
Top Applicants
Top 10 applicants by patent filingsfor class F22, 2013–2023, worldwide · Source: EPO PATSTAT
- XIAN THERMAL POWER RESEARCH INSTITUTE COMPANY 544
- SIEMENS DE 306
- PHILIP MORRIS PRODUCTS CH 258
- GENERAL ELECTRIC TECHNOLOGY CH 254
- MITSUBISHI HITACHI POWER SYSTEMS JP 235
- XIAN JIAOTONG UNIVERSITY 214
- MITSUBISHI HEAVY INDUSTRIES JP 195
- MITSUBISHI HITACHI POWER SYSTEMS 169
- HARBIN BOILER COMPANY 166
- VALMET TECHNOLOGIES FI 155