针对在役铆钉气隙受铆钉或者工件遮挡造成难以有效检测与定量评估的问题,建立ANSYS有限元仿真三维模型,开展垂向减震器座铆钉气隙的远场涡流检测仿真与试验研究。研究结果表明:有效电磁场可渗人铆钉孔约10mm深处,具有检测深度深,灵敏度高的优点;提出定量表征气隙的最优特征量,在检测信号的幅值、相位、实部、虚部这4个特征量中,信号虚部分量与铆钉气隙的线性相关系数高达0.999,最能表征气隙。试验测试结果与仿真结论相吻合,规律一致,证明研究成果的可信性。
Vertical absorber seat rail rivet hole gap in metro causes rivet loose easily, which endangers metro safety. Testing rail rivet hole gap of in service rivet was difficult because of the occlusion of rivet or workpiece. For this difficulty, this paper studied the remote field eddy current testing simulation of rail rivet hole gap. The results show that effective electromagnetic field can reach 10 mm deep below rivet ensure high sensitivity. Imaginary part can characterize gap better than amplitude, phase and real part for it’s linear correlation is 0.999. The experimental data tally with the simulation that proves reliable results.