Patent · US Expired

Self powered downhole tool anchor

US4429741A · kind A · utility

171Cited by
10References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 13, 1981
Grant dateFeb 7, 1984
Priority date
Expiry dateOct 13, 2001

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B23/065
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A self powered downhole tool anchor device (10) preattached to a downhole tool (T) and unitarily supported by a drill string (DS) for a single trip into a well bore, actuated by forceful engagement with the bottom or plug (P) in the well bore and attachment to a well bore casing (C). The anchor device comprises an inner mandrel (20) and lower cone (34) containing a piston (30) and fluid (F) for axially displacing an outer mandrel and piston (44) connected thereto by shear screws (46). An upper cone (20) on the outer mandrel is connected by shear pins to a slip housing (50) containing radially expandable slips (38) keyed to the lower cone (34). A self contained power supply (PS) of combustible material (M) is ignited by a firing pin (90) striking a primer igniter (I) and generates gas pressure applied to the piston 30 and fluid (F) to shear pin (46) and axially displace the outer mandrel and piston (44) upper cone (40) slip housing (50 ) slips (38) and ratchet ring (62) relative to inner mandrel (20) and cone (34). Screws (52) are then sheared off releasing upper cone (40) from slip housing (50) and allowing relative displacement therebetween to radially expand slips (38) into gripp…

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