PIEZOELECTRIC PRESSURE TRANSDUCER Russian patent published in 1996 - IPC

FIELD: equipment for detection of casing-to-well bore annulus overflows of fluids in cased wells. SUBSTANCE: pressure transducer has adapter casing 1 with holes for electric leads 2, and piezoelectric element 3. The latter is made in the form of a radially polarized ceramic cylinder. Current-conducting surfaces 4 of the piezoelectric element are connected to the electric leads. The piezoelectric element is positioned inside shell 3, made of a compound with a filler, and has through slot 6 in the cylinder element. The properties of the compound and ceramics are so selected that their coefficients of thermal expansion are the same, and the compound modulus of elasticity is lower than the ceramics modulus of elasticity at least by a factor of $$$. EFFECT: enhanced sensitivity, expanded frequency band and simplified design as compared with the known devices of the same application. 2 dwg