The Rapid Detection Techonogy Of Corrosion-resistant High-pressure Vessel Lining Layer

Buried defects of weld and defects of dorsal lining have become the major threat to the corrosion-resistant lining vessels with the widespread used. In this paper, ultrasonic testing of experimental research to the dorsal defects of stainless steel,and Lamb wave detection feasibility studied to the 316Mod urea grade stainless steel lining in thickness 8mm.This paper contributes to application of the rapid detection of corrosion-resistant high-pressure vessel lining layer.Summarized the factors which cause corrosion pressure vessel lining failure. Analysis the effect of stress distribution of urea lining plate gap based on ANSYS finite element method,The results show that, the liner gap increased rupture instability and failure probability of lining layer.Simulation analysis stress distribution of urea lining that be possessed dorsal defects, and calculated the stress corrosion craking of stainless threshod walue for 213MPa m1/2 of 316L stainless steel plate.Design a set of test lining blocks which have artificial dorsal defects with a certain size and shape. Compare different ultrasound parameters on the effect of ultrasonic defects detection through experimental research acquire ultrasonic testing parameters of 8mm thick 316Mod urea grade stainless steel plate, P wave probe, 2.5P13×13K1, coupling agent for the oil.It was going to ultrasonic testing the artificial defect specimen. Testing results showed that:ultrasonic flaw detection is sensitive to the depth of 0.3mm or more defects, the height of the defect echo is proportional to the depth of defect. On this basis, to achieve the ultrasonic detection on the lining blocks with natural defects, and accurate positioned and quantitated its internal defects.Obtained the dispersion curves of group velocity and phase velocity of 316Mod urea grade stainless steel plate by using Matlab software, for the first time Lamb wave testing technique 8mm thick stainless steel lining of the dorsal crack detection test. The results showed that it is feasible and reliable that the methodofdetection of lamb wave used on the 8mm thick 316Mod urea grade stainless steel dorsal crack of the technique, and can achieve a large area of detection, high testing efficiency, this methodofdetection should be popularized.