Main technical indicators of ultrasonic flaw detector

1. Sensitivity:
Sensitivity in ultrasonic flaw detection generally refers to the ability of the entire flaw detection system (instrument and probe) to find the smallest flaw. The smaller the defect, the higher the sensitivity.
The sensitivity of the probe of the instrument is usually measured by the sensitivity margin. Sensitivity margin refers to the total amount of attenuation required to make the echo of the specified reflector reach the reference height when the instrument is at maximum output (the gain and emission intensity are maximum, and the attenuation and suppression are 0). A large sensitivity margin indicates that the sensitivity of the instrument and the probe is high. The sensitivity margin is related to the comprehensive performance of the instrument and the probe, so it is also called the comprehensive sensitivity of the instrument and the probe.
2. Blind zone and initial pulse width:
Blind zone refers to the minimum distance from the detection surface to the defect that can be found. Defects in the blind zone cannot be found at all.
The initial pulse width refers to the continuation length of the initial pulse when the height on the screen exceeds 20% of the vertical amplitude under a certain sensitivity. The initial pulse width is related to the sensitivity, the higher the sensitivity, the larger the initial pulse width.
3. Resolution:
The resolution of the instrument and the probe refers to the ability to distinguish two adjacent defects on the screen. The smaller the distance between two adjacent defects that can be distinguished, the higher the resolution.
4. Signal-to-noise ratio:
The signal-to-noise ratio refers to the ratio of the useful minimum defect signal amplitude to the useless noise clutter amplitude on the screen. High signal-to-noise ratio and less clutter are beneficial to flaw detection. If the signal-to-noise ratio is too low, it is easy to cause missed detection or misjudgment, and in severe cases, it is even impossible to perform flaw detection.