E21C 25/22 Machines slitting solely by one or more cutter chains moving unidirectionally along jibs
Full Title
Cutting machines, i.e. for making slits approximately parallel or perpendicular to the seam (dislodging machines with slitting means E21C27/02, E21C27/10, E21C27/18) > Machines slitting solely by one or more cutter chains moving unidirectionally along jibs
Filing statistics
CPC E21C 25/22 belongs to the parent subclass E21C, which recorded 16,559 patent applications worldwide between 2013 and 2023. Annual filings grew from 828 in 2013 to 1,605 in 2023 (+94%), peaking at 1,908 applications in 2021. The most active applicants in class E21 are HALLIBURTON ENERGY SERVICES GROUP (27,652 applications), SAUDI ARABIAN OIL COMPANY (7,755 applications) and PETROCHINA COMPANY (7,025 applications).
Source: EPO PATSTAT, worldwide filings
4 direct subcodes
Child Classifications
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- E21C 25/24 with flat jibs only
- E21C 25/26 with curved jibs only
- E21C 25/28 Chains or chain guides
- E21C 25/50 with equipment for cleaning the slit (associated with rotary-rod or rotary-drum machines E21C25/14)
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