Patent · US Expired

Apparatus for unscrewing drill pipe sections

US5996444A · kind A · utility

24Cited by
5References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 30, 1997
Grant dateDec 7, 1999
Priority date
Expiry dateOct 30, 2017

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B19/163
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Pipe sections of a drill string are unscrewed by holding one pipe section stationary in a clamping arm, and rotating another pipe section by a turning wrench. The clamping arm includes an adapter that can be replaced by similar adapters sized for different pipe diameter. The turning wrench includes a lug arranged to be contacted by a piston rod and rotated thereby for breaking the bond between the pipe sections.

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