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PCE
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DIFF Subgroup
C21D 1/34

Methods of heating (C21D1/06 takes precedence)

Introduced: September 1968

Title

Titles differ between systems:

IPC: Methods of heating

CPC: Methods of heating (C21D1/06 takes precedence)

Full Title

Full titles differ between systems:

IPC:

General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering > Methods of heating

CPC:

General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering > Methods of heating (C21D1/06 takes precedence)

IPC and CPC are identically structured here. All 6 subcodes exist in both systems.

Child Classifications

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  • C21D 1/38 Heating by cathodic discharges IPC+CPC Available in IPC and CPC
  • C21D 1/40 Direct resistance heating IPC+CPC Available in IPC and CPC
  • C21D 1/42 Induction heating IPC+CPC Available in IPC and CPC
  • C21D 1/52 with flames IPC+CPC Available in IPC and CPC
  • C21D 1/53 Heating in fluidised beds since 1980 IPC+CPC Available in IPC and CPC

Top Applicants

Top Applicants (IPC)

Class C21,2013–2023, worldwide · Source: EPO PATSTAT

  1. JFE STEEL JP 7,470
  2. POSCO (POHANG IRON AND STEEL COMPANY) KR 4,615
  3. JFE STEEL 4,538
  4. NIPPON STEEL CORPORATION JP 4,536
  5. ARCELORMITTAL LU 2,597
  6. NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 2,241
  7. ANGANG STEEL COMPANY 2,126
  8. NSSMC (NIPPON STEEL & SUMITOMO METAL) 1,783
  9. BAOSHAN IRON & STEEL COMPANY 1,620
  10. HYUNDAI STEEL COMPANY KR 1,545

Top Applicants (CPC)

Class C21,2013–2023, worldwide · Source: EPO PATSTAT

  1. JFE STEEL JP 8,270
  2. NIPPON STEEL CORPORATION JP 5,222
  3. POSCO (POHANG IRON AND STEEL COMPANY) KR 4,824
  4. JFE STEEL 3,311
  5. ARCELORMITTAL LU 3,239
  6. NSSMC (NIPPON STEEL & SUMITOMO METAL) JP 2,659
  7. HYUNDAI STEEL COMPANY KR 1,492
  8. ANGANG STEEL COMPANY 1,318
  9. BAOSHAN IRON & STEEL COMPANY 1,233
  10. KOBE STEEL JP 1,228