E21B25/12 - CPC Classification Index

ClassID:

135422 ⎘

E21B25/12 - CPC Classification

Classification description:

Apparatus for obtaining or removing undisturbed cores, e.g. core barrels, core extractors; Formed core retaining or severing means of the sliding wedge type

Recent Application in this class:

20220213750

2022-07-07

Core barrel sealing structure capable of increasing sealing-specific pressure

20170292340

2017-10-12

Apparatus and method for withdrawing cores from drilled holes

20170284160

2017-10-05

Core lifter

20150322722

2015-11-12

Coring tools and related methods

20110203855

2011-08-25

DRILLING AND CORE REMOVAL APPARATUS AND METHOD

20110100718

2011-05-05

Core lifter

20090000822

2009-01-01

Rock core removal method and apparatus