A novel sensor to measure the biased pulse magnetic response in steel stay cable for the detection of surface and internal flaws

摘要

Highlights?Biased pulse magnetic response in steel stay cable are measured for flaws assessment.?The novel sensor possess the characters of flexibility and low power consumption.?Both the surface notches and internal broken wire flaws in the cable is detectable.AbstractA new type of sensor is designed to measure the biased pulse magnetic response in a large-diameter steel stay cable for the assessment of both surface and internal flaws. The sensor deploys two parallel-connected flexible flat coils (FFC) fed with a biased pulse current as the electromagnet for cable magnetization. A tunnel magneto-resistive (TMR) device and two series-connected sensing coils are used to measure the surface magnetic flux leakage (MFL) and the main-flux variation in the defective cable, respectively. A comparative study between the weak and near-saturated magnetization states of a defective cable is performed by finite element simulation tools to investigate the flaw detection ability of both the surface MFL and main-flux me