Eddy Current Array Instrument and Probe for Crack Detection of Aircraft Tubes

Abstract

Failure of aircraft tubes inspections is decidedly hazardous. However, conventional eddy current testing for tubes is very time-consuming. Eddy current array technology can dramatically decrease the inspection time by reducing to one the number of rotations needed to completely cover the tube surface. A new eddy current array instrument and probe was presented, the ECA imaging principle and the hardware frame of the system was described. By means of FEM simulation, optimize the parameter of the eddy current array probe. Based on the instrument and probe, the aircraft oil deliver EDM north with an axial crack was detected. The experimental results show that not only the instrument and probe are able to identify the existence of cracks quickly and effectively, but also estimate the location of cracks. Further studies have shown that the inspection resolution is the length of cracks with tolerance ±2 mm and the depth of cracks with tolerance ±20%.

Autonomous Maintenance for Through-Life Engineering

“…The use of magnetic flux leakage (MFL) techniques are common [13,14], and eddy current arrays (ECAs) have also been used in an autonomous NDT approach within the aerospace industry for routine inspection of fatigue crack detection of aircraft oil delivery tubes [15].…”

Array Sensor Output Signal Detection System Signal Conditioning Circuit Design

“…Array detection is an emerging branch of non-destructive testing technology. It uses computer and digital signal processing technology to achieve rapid and effective detection of materials and components through the special design of the detection sensor structure [1][2]. Due to the small number of turns of the detection coil of the planar array sensor, the output signal is very weak and easily affected by the background noise [3].…”

Multi-Frequency Magnetic Induction Tomography System and Algorithm for Imaging Metallic Objects

“…Non-destructive testing and eddy-current testing (NDT and ECT, respectively) of metal components has been extensively investigated and successfully adopted as a tool in industry. However, in using ECT to render images for detecting corrosion [ 10 , 11 , 12 , 13 , 14 ], fatigue [ 15 , 16 ], defects [ 17 , 18 , 19 ] and physical loading [ 20 , 21 , 22 ], mechanical scanners are often employed [ 23 , 24 , 25 , 26 , 27 , 28 ]. Furthermore, while ECT is generally regarded as non-contact, close proximity sensor positioning is usually required.…”

“…Eddy-current crack detection in metal components, again using high-frequency excitation fields, has also been demonstrated. The abrupt discontinuity in surface conductivity, associated with cracks, interrupts the flow of induced currents [ 18 , 19 , 26 , 27 , 28 , 39 , 40 , 41 ]. Crack depth is reflected in the detected signal magnitude, but is also dependent upon sensor positioning relative to the sample (lift-off effect).…”