Patent · US Expired

Methods for determining the stuck point of a conduit in a borehole

US4105070A · kind A · utility

11Cited by
9References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 19, 1977
Grant dateAug 8, 1978
Priority date
Expiry dateSep 19, 1997

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B47/09
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

In the representative manner of practicing the new and improved method disclosed herein, a so-called "stuck-point indicator" or "freepoint-indicator" tool including a unique deformation-responsive sensor tandemly arranged between unique upper and lower tool anchors is positioned in a string of well pipe believed to be stuck in a well bore. The tool is then moved to a selected depth location in the pipe string and, in keeping with the principles of the present invention, operated so that the upper anchor is engaged with the pipe string wall before the lower anchor is engaged. Thereafter, upon application of forces to the upper end of the pipe string, independent measurements are produced by the sensor which are respectively representative of tensional forces and torsional forces acting on that portion of the pipe string between the upper and lower anchors.

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