Patent · US Expired

Process and drilling equipment for sinking a well in underground rock formations

US5205364A · kind A · utility

8Cited by

7References

25Claims

0Family size

Inventors

Rainer Juergens · Celle, DE
Friedhelm Makohl · Hermannsburg, DE

Key dates

Filing date	Jul 30, 1991
Grant date	Apr 27, 1993
Priority date	—
Expiry date	Jul 30, 2011

Classification

Technology area (CPC E)Fixed Constructions
CPC primaryE21B44/005
WIPO fieldCivil engineering
WIPO sectorOther fields

Abstract

The present invention is a drilling tool including a telescoping assembly for transmitting hydraulic force to the drill bit at the bottom of the tool. The internal hydraulic characteristics of the tool may be varied to vary the force through extension and retraction of the telescoping assembly.

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