Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors (core bits E21B10/02)

Introduced: September 1968

Title

Titles differ between systems:

IPC: Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors

CPC: Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors (core bits E21B10/02)

Full titles differ between systems:

IPC:

Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors

CPC:

Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors (core bits E21B10/02)

Core bits

Of 7 combined children, 6 exist in both systems.

1 codes are CPC-only extensions.

2 shared codes have differing titles between IPC and CPC.

IPC defines codes here since 1980.

Navigate with arrow keys, Enter to open

E21B 25/005 CPC only CPC only
E21B 25/02 the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe since 1980 IPC+CPC Available in IPC and CPC
E21B 25/06 the core receiver having a flexible liner or inflatable retaining means since 1980 IPC+CPC Available in IPC and CPC
E21B 25/08 Coating, freezing, consolidating cores (E21B25/06 takes precedence); Recovering uncontaminated cores or cores at formation pressure since 1980 IPC+CPC Available in IPC and CPC
E21B 25/10 Formed core retaining or severing means (E21B25/06, E21B25/08 take precedence) since 1980 IPC+CPC Available in IPC and CPC
E21B 25/16 for obtaining oriented cores since 1980 IPC+CPC Available in IPC and CPC
E21B 25/18 the core receiver being specially adapted for operation under water since 1980 IPC+CPC Available in IPC and CPC

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

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