IPC Subgroup
E21C 27/32 by adjustable or non-adjustable planing means with or without loading arrangements
Introduced: September 1968
Last revised: January 2006
Full Title
Machines which completely free the mineral from the seam > Mineral freed by means not involving slitting > by adjustable or non-adjustable planing means with or without loading arrangements
Classification Context
- Section:
- FIXED CONSTRUCTIONS
- Class:
- EARTH OR ROCK DRILLING; MINING
- Subclass:
- MINING OR QUARRYING
Related Keywords
PLANING in mining or quarrying
6 direct subcodes
Child Classifications
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- E21C 27/34 Machine propelled along the working face by cable or chain
- E21C 27/36 Machine self-propelled along the working face
- E21C 27/38 Machine stationary while planing in an arc
- E21C 27/4 Machine and its planing tool making alternative step-wise movements along the working face
- E21C 27/42 combined with scraper or collector box
- E21C 27/44 Planing knives
Top Applicants
Top 10 applicants by patent filingsfor class E21, 2013–2023, worldwide · Source: EPO PATSTAT
- HALLIBURTON ENERGY SERVICES GROUP US 26,607
- PETROCHINA COMPANY 14,382
- SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
- CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
- BAKER HUGHES US 6,269
- SCHLUMBERGER TECHNOLOGY US 5,929
- SAUDI ARABIAN OIL COMPANY SA 5,880
- SOUTHWEST PETROLEUM UNIVERSITY 4,477
- CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
- SCHLUMBERGER TECHNOLOGY NL 4,219