PROCEDURE MEASURING THICKNESS OF ARTICLE WITH USE OF ULTRASONIC PULSES Russian patent published in 2004 - IPC

FIELD: instrumentation, nondestructive testing.

SUBSTANCE: invention can find use in thickness measurement, flaw detection, study of structures of various materials and articles. Procedure includes radiation of ultrasonic pulse into material of article and reception of pulses reflected many times from opposite surfaces of material. Gating isolates from received sequence of pulses part of sequence from moment when amplitude of interference from inherent damping noises grows smaller than amplitude of pulses received from material to moment when amplitude of received pulses falls to medium level of various noises accompanying reception of ultrasonic pulses from material. Normalized autocorrelation function from gated part of received sequence of pulses is computed. Argument of autocorrelation function not equal to zero at which this function reaches maximum is found. Thickness is computed as product of half of this argument by known velocity of propagation of ultrasonic pulses in material.

EFFECT: enhanced authenticity, accuracy and stability of readings.

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