The invention discloses a crack defect quantification method and device based on
magnetic flux leakage space integration. The method comprises the following steps: converting crack defect
magnetic flux leakage signals under different lift-off values into analog
voltage signals; carrying out integral operation on the crack defect
magnetic flux leakage analog signals under different lift-off values by combining a mileage sampling trigger
signal; sampling the output of the integral operation to obtain a first
magnetic flux leakage signal integral value corresponding to the first lift-off value and a second
magnetic flux leakage signal integral value corresponding to the second lift-off value; constructing an iterative equation to obtain a half-width quantitative numerical solution of the crack defect; obtaining a depth quantitative analytic solution of the crack defect according to a leakage
magnetic field integration method; and outputting a quantitative size result of the crack defect. According to the invention, problems which may occur when a conventional
magnetic flux leakage detection
system directly samples a leakage
magnetic field, such as leakage of crack magnetic flux leakage signals or loss of effective magnetic flux leakage signals, can be avoided; the theoretical model is clear, the calculation speed is high, the calculation result is accurate, and the crack
defect size quantification efficiency is high.