Calibration of Ultrasonic Flaw Detectors

Abstract

Abstract:A calibration system for ultrasonic flaw detectors has been developed at the Government of the Hong Kong Special Administrative Region Standards and Calibration Laboratory (SCL) in accordance with the international standard EN12668-1:2010. The calibration covers all the periodic and repair tests (the Group 2 tests) required in the standard for checking the performance of ultrasonic instruments, including their stability, transmitter pulse parameters, receiver response parameters, and time-base linearity. During the calibration, the ultrasonic flaw detector's transmitter is connected to a combination of a delay generator and function generator which simulates a delayed version of the transmitted signal as the reflected signal. The simulated reflected signal is then fed to the receiver of the ultrasonic flaw detector. The stabilities over time and voltage variation of the received waves are measured and the receiver frequency response is obtained. Other performance parameters of the receiver such a...