DEVICE FOR PREDICTING RESIDUAL LIFE OF METAL OBJECTS Russian patent published in 2009 - IPC G01N29/14 

FIELD: physics; measurement.

SUBSTANCE: invention can be used for predicting residual life of metal objects. Acoustic transducers are fitted on the object and the object is loaded with a test load. The object is kept under constant test load and acoustic emission signals are recorded. Parametres of the acoustic emission signals are measured and spectra of acoustic signals are calculated from these parametres. The time at which signals reach the acoustic transducers is recorded and coordinates of the developing defects are calculated. The object is divided into n sections, containing not less than three acoustic transducers in each, where a strain gauge is fitted. The object is loaded with static a load which exceeds the operating load by (20-25)%. Acoustic emission signals are localised in each sector and for each of the localised sources, integral characteristics are determined: S_xy - integral characteristic of the energy of the acoustic emission signal source and Q_xy - integral characteristic of correlation of the x^th acoustic emission signal source in the y^th sector of the object. After that the deviation ranges of stress in places where there are strain gauges Ψ_α are determined and from the value of integral characteristics S_xy, Q_xy, deviation of stress Ψ_α for the corresponding zone, the degree of damage is determined, from which the residual life of the object is determined.

EFFECT: more reliable determination of residual life.