Patent · US Expired

Alarm system for measurement while drilling oil wells

US4802143A · kind A · utility

46Cited by
45References
45Claims
0Family size

Inventor

Key dates

Filing dateApr 16, 1986
Grant dateJan 31, 1989
Priority date
Expiry dateApr 16, 2006

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B49/005
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A detector for use in wells comprises a collar member connected to a drill string at a position down-well with respect to the surface of the earth, a sensor in the collar in the area being monitored for sensing down-well fluids in deep wells, an impulse generator cavity in the collar, an acoustic impulse generator mounted in the impulse generator cavity for producing a deformation wave in the drill string, having longitudinal, torsional and radial components, an elongated fluid sampling cavity in the collar having lower and upper ends and inlet and outlet means, respectively, in the lower and upper ends for allowing the passage of down-well fluids through the sampling cavity, such fluids being primarily mixtures of mud and oil and mixtures of mud, oil and gas. The sensor is supported within the sampling cavity in a position so that when gas enters into the cavity in abnormal amounts, separation of the components of the mixture produces variations in thermal conductivity properties sensed by the sensor. The sensor is operatively connected to the impulse generator to actuate the generator when a predetermined threshold concentration of undesirable fluid is exceeded in the sampling ca…

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