Patent · US Expired

Guide tube of a drill string configured to facilitate unscrewing thereof from a member of the drill string

US6681875B2 · kind B2 · utility

13Cited by
8References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 22, 2001
Grant dateJan 27, 2004
Priority date
Expiry dateJan 16, 2022

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/0426
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A guide tube for use in a rock drill string includes a main portion, a sleeve disposed at a first end of the main portion, and a male thread portion disposed at a second end of the main portion. The sleeve forms a recess having a female thread. A flush channel extends through the guide tube. The main portion includes a section of reduced cross-section disposed adjacent the sleeve for defining a generally radially extending shoulder between the waist and the sleeve. The shoulder serves to support the guide tube on a rig as percussion is applied to the guide tube for loosening a threaded joint between the guide tube and another member.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.