The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 14, 2002
Filed:
Aug. 08, 2000
Applicant:
Inventor:
Shohei Kato, Tokyo, JP;
Assignee:
Japan Drilling Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B 1/010 ;
U.S. Cl.
CPC ...
E21B 1/010 ;
Abstract
By using a reaming machine which arranges a plurality of hydraulic hammer driven drill bits in parallel on a cross section to be reamed, a horizontal or gently inclined pilot hole is reamed. A pressurized water introducing drill pipe and a drill pipe as a discharge pipe are connected to the reaming machine, a seal which forms a sealing between the drill bits and a reamed hole is provided, and a passage for feeding drilling water into the drill pipe is provided, whereby the reaming machine can be propelled while discharging cuttings with a small amount of water through the drill pipe.