METHOD AND DEVICE FOR DETERMINATION OF REMAINING SERVICE LIFE OF THIN-WALLED ENVELOPES MADE FROM RESERVOIR AND PIPE STEELS Russian patent published in 2004 - IPC

FIELD: prediction of remaining service life of thin-walled envelopes by means of nondestructive testing and diagnosis.

SUBSTANCE: proposed method includes random check of thin-walled envelopes and reception of information on degree of deviation from standard specimen; method includes also access of information pertaining to degree of deviation of electromagnetic field parameters (oe/m) of thin-walled envelope under test from standard specimen; then, present magnitudes of safety factor of impact viscosity and safety factor of thickness of envelope are calculated; method includes also mathematical expectation of average remaining service life of object under test and its square deviation and 95-% remaining service life is determined. Device proposed for realization of this method includes differential-transformer transducer, AC generator and measuring unit; differential-transformer transducer i mounted for rotation about its axis at fixed point of measurement includes two inductance coils located axially relative to each other and provided with separate cores; they are separated from each other by magnetically soft partition; one inductance coil is connected through switching unit either to automatic equilibrium AC bridge for measuring the oe parameters of filed characterizing the remaining thickness of object under test or to milliamperemeter for measuring the oe parameters of field characterizing impact viscosity of object under test; second inductance coil is either disconnected or is connected to AC generator.

EFFECT: enhanced durability, accuracy and reliability of prediction of remaining service life.

3 cl, 1 dwg