CPC Subgroup
E21C 35/22 Equipment for preventing the formation of, or for removal of, dust (picks with arrangement of fluid-spraying nozzles E21C35/187; )
Full Title
Details of, or accessories for, machines for slitting or completely freeing the mineral from the seam, not provided for in groups E21C25/00 - E21C33/00, E21C37/00 or E21C39/00 > Equipment for preventing the formation of, or for removal of, dust (picks with arrangement of fluid-spraying nozzles E21C35/187; )
3 direct subcodes
Child Classifications
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- E21C 35/23 Distribution of spraying-fluids in rotating cutter-heads
Top Applicants
Top 10 applicants by patent filingsfor class E21, 2013–2023, worldwide · Source: EPO PATSTAT
- HALLIBURTON ENERGY SERVICES GROUP US 27,652
- SAUDI ARABIAN OIL COMPANY SA 7,755
- PETROCHINA COMPANY 7,025
- BAKER HUGHES US 6,589
- SCHLUMBERGER TECHNOLOGY US 6,151
- SINOPEC (CHINA PETROCHEMICAL CORPORATION) 4,443
- SCHLUMBERGER TECHNOLOGY NL 4,255
- CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 3,991
- SERVICES PETROLIERS SCHLUMBERGER FR 3,300
- SCHLUMBERGER CANADA CA 3,086