INSULATOR FOR INDEPENDENT ACOUSTIC LOGGING DEVICE Russian patent published in 2017 - IPC G01V1/52 G01V1/40 

FIELD: geophysics; manufacturing technology.

SUBSTANCE: invention relates to geophysics and can be used during acoustic logging. According to the present disclosure, proposed is an insulator for an independent acoustic logging device containing an outer bearing body made of a fiber glass pipe with steel ends, as well as an elastic vibration absorber consisting of alternating elements with contrast wave impedance in the form of rubber and metal washers. Herewith the rubber washers contain a fine powder of heavy metals and include large-size balls or rollers from a heavy metal arranged regularly along the circle in every washer. Additionally introduced is an inner steel pipe, the hole of which is a through channel for the flushing liquid, and in a sealed from the ambient medium annular space between external and internal pipes filled with a silicone liquid there is the elastic vibration absorber of rubber and metal washers. Jointing assemblies are made in the form of transient heads, which are acoustically isolated from the internal pipe and are made with the possibility of longitudinal movement without rotation. Herewith there is a compensator of ambient pressure and temperature change of the silicone liquid volume. Besides, the elastic vibration absorber of rubber and metal washers is pressed and fixed on both sides by metal bushings to create the required contact of the rubber washers with the external and internal pipes. Rubber washers are made with a thickness equal to a quarter wavelength for the main frequency of a monopole radiation or equal to a quarter wavelength for a set of frequencies corresponding to the range of frequencies of the monopole radiation, besides, the rubber washers are made with a specified wave impedance from a silicon rubber of low viscosity. On the external surface of the internal pipe there are longitudinal slots for transit wires, which are covered with a thin-walled protective sleeve to prevent deformation of the rubber washers in the slots at pressing the absorber and to protect the transit wires. In the transient heads there are one or several sealed leads installed with the required amount of contacts providing a sealed cavity of the insulator and an electrical connection both inside the insulator with the transit wires and with jointed units, as well as there are additional electric connectors of an untight type for jointing with units of radiators and the receiving antenna. Compensator of ambient pressure and temperature change of the silicone liquid volume is implemented with an elastic membrane or a piston.

EFFECT: higher acoustic efficiency of the insulator at high structural strength due to unloading the bearing pipe by filling the internal cavity with a silicone liquid.

9 cl, 1 dwg