Title:
CORE BARREL FOR EXTRACTING ROCK-CORE, DRILL ROD AND SWIVEL JOINT
Document Type and Number:
Japanese Patent JP3971015
Kind Code:
B
Abstract:
PROBLEM TO BE SOLVED: To provide a rock-core extracting core barrel not to roughen an excavated hole wall by the flow of a sludge.
SOLUTION: A second outer tube assembly 12 is unitedly provided through water passing gaps 23, 25 inside a first outer tube assembly 11 to axially move as it rotates. An inner tube assembluy 13 is slidably fitted inside the second outer tube assembly 12 through water passing gaps 24, 26. The inner tube assembly 13 is engaged with or disengaged from the second outer tube assembly 12 by a latch device 14.
Inventors:
Kawahara, Masaki
Kitani, Yasuo
Kitani, Yasuo
Application Number:
JP1998000056670
Publication Date:
June 15, 2007
Filing Date:
March 09, 1998
Export Citation:
Assignee:
NLC:KK
GEO ENGINEERING:KK
GEO ENGINEERING:KK
International Classes:
E21B25/00; E21B17/00; E21B17/05; E21B25/00; E21B17/00; E21B17/02; (IPC1-7): E21B25/00; E21B17/00; E21B17/05