BOREHOLE CALIPER Russian patent published in 2010 - IPC E21B47/10 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry, particularly to control of development of oil and gas deposits. Borehole caliper contains hollow cylindrical metal case with located in its cavity sensor of heat loss anemometre. Sensor of heat loss anemometre is electrically isolated of casing. Additionally casing is excluded to electrical circuit as one of electrodes of cylindrical turning condenser. Part of external surface of casing from the side of ending is implemented as conical and is installed in downhole sensor through electric insulator, implemented in the form truncated cone of material with high mechanical strength and low dielectric permeability. The rest external surface of casing is covered by dielectric layer, stable to impact of aggressive downhole medium. In inner volume of casing it is additionally installed acoustical emission sensor, implemented in the form of hollow cylindrical piezoelectric element with providing of rigid mechanical contact with internal surface of casing and electrical insulation from it.

EFFECT: extension of functional capabilities of sensor.

1 dwg