Patent · US Expired

Hydraulic power unit for measurement while drilling apparatus

US4483394A · kind A · utility

12Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 1, 1982
Grant dateNov 20, 1984
Priority date
Expiry dateNov 1, 2002

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B47/20
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A hydraulic power unit is provided for a downhole instrument of a measurement while drilling system for a well drilling. The hydraulic power unit is enclosed within a drill collar that is connected in the drill string of a rotary drilling rig. An outer body sleeve is rigidly mounted in the instrument drill collar. A fixed inner sleeve is connected to the outer body sleeve in a concentric relation with a longitudinally movable plunger assembly supported therebetween and movable in the telescopic fashion between an extended position and a retracted position to provide hydraulic power fluid for the hydraulically powered circuits of the instrument.

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