Patent · US Expired

Hydraulic circuit for use in wireline formation tester

US4845982A · kind A · utility

24Cited by
10References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 20, 1987
Grant dateJul 11, 1989
Priority date
Expiry dateAug 20, 2007

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B49/10
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

In a formation tester constructed with an extendable probe driven by hydraulic means, the means being connected to a hydraulic circuit, an improved apparatus is set forth which includes a hydraulic fluid multiplier means. This multiplier means is connected between the pump and the means extending the probe and backup shoes. The multiplier means incorporates a step piston and a large cylinder having a step conforming with the piston. Suitable seals are placed on the piston. The piston drives initially to deliver a high volume low pressure flow to extend rapidly the probe, and completes its operation with a low volume high pressure flow to assure proper setting. This enables more rapid operation and more rapid completion of formation testing.

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