Local water leaching coupling manner based medium plate ultrasonic testing method employing single crystal straight probes

Abstract

The invention provides a local water leaching coupling manner based medium plate ultrasonic testing method employing single crystal straight probes. By the single crystal straight probes, and in a local water leaching coupling manner and a real-time interface wave gate tracking manner, ultrasonic testing is carried out on defects of medium plates through a multi-channel automatic plate detection technology for evaluating the defects through a first flaw wave and a first bottom wave under different sensitivity conditions. The method comprises the following steps: by the single crystal straight probes and a time sharing mechanism, and in the local water leaching coupling manner, obtaining echo signals from each region of a medium plate through the multi-channel single crystal straight probes and carrying out analogue-to-digital conversion; judging whether defects exist or not according to converted echo data; if so, generating an interrupt signal, and transmitting the interrupt signal and the echo data to a processor; and forming an A scanning image by the processor and obtaining the equivalent size of the defect according to the interrupt signal and the echo data, and converting the A scanning image into a C scanning image according to an echo amplitude height, a sonic path distance position and a flaw judgment standard. According to the method provided by the invention, the requirements for detecting the defects of the medium plates can be effectively met; the probe abrasion is reduced; and the practicability is relatively high.

Description

technical field [0001] The invention relates to the technical field of ultrasonic nondestructive testing, in particular to an ultrasonic testing method for medium and thick plates based on a single crystal straight probe in a local water immersion coupling mode. Background technique [0002] Ordinary steel plates are rolled from slabs, and slabs can be made by casting or billet rolling or forging. Ordinary steel plates include carbon steel, low alloy steel, austenitic steel plate, nickel and nickel alloy plate and double Compared with stainless steel plates, etc. Common defects in the board include delamination, folding, white spots, etc., and cracks are rare. Delamination is a separation layer formed by shrinkage cavities and slag inclusions in the slab that are not fused during the rolling process. Delamination destroys the overall continuity of the steel plate and affects the strength of the steel plate to withstand the tensile stress of the vertical plate surface. The...

AI Technical Summary

Problems solved by technology

Due to the large number of multi-channel automatic ultrasonic detection probes and fast detection speed, the surface of the hot rail steel plate is rough, the probes wear quickly, and the energy of the dual crystal straight probes is weak, so it is only suitable for the detection of medium and thick plates with a thickness less than 60mm

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