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DIFF Main Group
E21B 47/00

Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B21/08)

Introduced: September 1968

Title

Titles differ between systems:

IPC: Survey of boreholes or wells

CPC: Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B21/08)

Full Title

Full titles differ between systems:

IPC:

Survey of boreholes or wells

CPC:

Survey of boreholes or wells (monitoring pressure or flow of drilling fluid E21B21/08)

Additional Content IPC

Glossary

borehole boreholes an unlined shaft drilled into the ground, typically for the purposes of extracting water, crude oil or natural gas this is often referred to as the wellbore.

Limiting references

Monitoring pressure or flow of drilling fluid

Of 16 combined children, 15 exist in both systems.

1 codes are CPC-only extensions.

3 shared codes have differing titles between IPC and CPC.

Child Classifications

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  • E21B 47/001 for underwater installation since 2012 IPC+CPC Available in IPC and CPC
  • E21B 47/003 Determining well or borehole volumes since 2012 IPC+CPC Available in IPC and CPC
  • E21B 47/005 Monitoring or checking of cementation quality or level since 2012 IPC+CPC Available in IPC and CPC
  • E21B 47/006 CPC only CPC only
  • E21B 47/007 Measuring stresses in a pipe string or casing (for locating blocked portions of pipes E21B47/09) since 2012 IPC+CPC Available in IPC and CPC
  • E21B 47/26 Storing data down-hole, e.g. in a memory or on a record carrier since 2012 IPC+CPC Available in IPC and CPC

Top Applicants

Top Applicants (IPC)

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

Top Applicants (CPC)

Class E21,2013–2023, worldwide · Source: EPO PATSTAT

  1. HALLIBURTON ENERGY SERVICES GROUP US 27,652
  2. SAUDI ARABIAN OIL COMPANY SA 7,755
  3. PETROCHINA COMPANY 7,025
  4. BAKER HUGHES US 6,589
  5. SCHLUMBERGER TECHNOLOGY US 6,151
  6. SINOPEC (CHINA PETROCHEMICAL CORPORATION) 4,443
  7. SCHLUMBERGER TECHNOLOGY NL 4,255
  8. CNPC (CHINA NATIONAL PETROLEUM CORPORATION) 3,991
  9. SERVICES PETROLIERS SCHLUMBERGER FR 3,300
  10. SCHLUMBERGER CANADA CA 3,086