Simulation Analysis of Near and Remote Field Pulse Eddy Current Composite Detection Method for Single-Metal Pipeline

Pipeline integrity is crucial for safely transporting energy resources. Traditional electromagnetic non-destructive testing (NDT) methods like eddy current testing (ECT) face limitations in detecting deep defects due to the skin effect. This study proposes a novel near and remote field pulse eddy current composite detection method that integrates pulsed eddy current testing and pulsed remote field eddy current testing to enhance defect detection and localization. A simulation model was established, showing the feasibility of the composite probe. The study demonstrated that the proposed method can distinguish between defects on the inner and outer walls of the pipeline. Parameter optimization identified 25 Hz as the optimal excitation frequency and a 50% duty cycle for the excitation signal. A three-layer shielding disc of copper, silicon steel, and copper (1: 1: 4) provided the best shielding effectiveness. The near and remote field pulse eddy current composite detection method improves detection capabilities and accuracy, enabling precise identification of inner and outer wall defects.