Skip to content
Search Classifications
Search for IPC and CPC classification codes or keywords
IPC Main Group
E21B 43/00

Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells

Introduced: September 1968

Last revised: January 2006

Classification Context

Section:
FIXED CONSTRUCTIONS
Class:
EARTH OR ROCK DRILLING; MINING
Subclass:
EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS

Additional Content

Installations or methods for obtaining, collecting or distributing water

Related Keywords

drilling for OIL(S)obtaining OIL(S) from deep wellsobtaining WATER from deep wells

14 direct subcodes

Child Classifications

Navigate with arrow keys, Enter to open

  • E21B 43/12 Methods or apparatus for controlling the flow of the obtained fluid to or in wells
  • E21B 43/14 Obtaining from a multiple-zone well
  • E21B 43/28 Dissolving minerals other than hydrocarbons, e.g. by an alkaline or acid leaching agent
  • E21B 43/285 Melting minerals, e.g. sulfur
  • E21B 43/29 Obtaining a slurry of minerals, e.g. by using nozzles
  • E21B 43/295 Gasification of minerals, e.g. for producing mixtures of combustible gases
  • E21B 43/3 Specific pattern of wells, e.g. optimising the spacing of wells
  • E21B 43/32 Preventing gas- or water-coning phenomena, i.e. the formation of a conical column of gas or water around wells

Top Applicants

Top 10 applicants by patent filingsfor class E21, 2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 26,607
  2. PETROCHINA COMPANY 14,382
  3. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 10,137
  4. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 6,517
  5. BAKER HUGHES US 6,269
  6. SCHLUMBERGER TECHNOLOGY US 5,929
  7. SAUDI ARABIAN OIL COMPANY SA 5,880
  8. SOUTHWEST PETROLEUM UNIVERSITY 4,477
  9. CHINA UNIVERSITY OF MINING AND TECHNOLOGY 4,357
  10. SCHLUMBERGER TECHNOLOGY NL 4,219