The present invention provides a surface property inspection method including a step of setting a resistance ratio between resistors R1 and R2 of an AC bridge circuit 20 in a surface properly inspection apparatus 1. The step includes a step for placing a non-surface-treated reference test pieces S on a reference detector 22 and an inspection detector 23 and measuring a first setting output signal while changing the resistance ratio , a step for placing the reference test piece S on the reference detector 22, placing a surface-treated setting test piece on the inspection detector 23, and measuring a second setting output signal while changing the resistance ratio, a step for calculating the differential value between the first and second output signals, and a step for setting the resistance ratio so that the absolute value of the differential value is maximized.

A method of examining a wheel or rim on site is provided using an eddy current array probe in electronic communication with a computer, the computer having a processor and a memory, the memory to provide instructions to the processor. The method involves standardizing the eddy current array probe with a reference standard, adjusting the eddy current array probe with a lift off screw to provide a suitable distance between the probe and a surface of the wheel or rim, scanning the wheel or rim with an alternating current, sending a data set to the computer, the computer analyzing the data set, and the computer displaying a three-dimensional image of the data set on a user interface. This method is particularly developed for off road vehicles at mining sites or any off road vehicle wheels and rims.

In the method for determining the electrical conductivity in samples by an eddy current sensor, an alternating electrical field is excited at a known measurement frequency, an alternating electromagnetic field which is directed against the alternating electrical field is thereby formed, detected by a suitable detector, and the complex impedance is determined, which procedure is repeated at different known measurement frequencies, once in air and once with the same measurement frequencies at a calibration body, differences of the real and imaginary portions and of the measured values in air and over the calibration body are then divided by the respective measurement frequency, wherein a product is associated with each value pair R/ and X/=L in accordance with the associated measurement frequency w and the known conductivity a of the calibration body and a locus is presented in a Nyquist diagram.

A calibration system for an electromagnetic (EM) tool includes a processor. The processor employs the EM tool to measure responses at each of a plurality of channels. The processor records the measured responses at each of the channels in an EM data log for the channel. The processor determines a nominal value of each of the channels, as being equal to a histogram peak of the EM data log. The processor selects one or more calibration points from the EM data log for a particular channel, based on a difference between the nominal value of the particular channel and the measured response at the calibration point being greater than a particular threshold. The processor determines a plurality of parameters by reducing a misfit between synthetic data and both the nominal values of the channels and the measured responses of the channels at the selected one or more calibration points.

Apparatus and methods for real-time fusion of data acquired using ultrasonic and eddy current area sensors during nondestructive examination. The ultrasonic data is acquired using an array of ultrasonic transducer elements configured to enable the production and display of a C-scan of a small area. The ultrasonic transducer array may be one- or two-dimensional. The eddy current sensor can be a single pair of induction coils, a multiplicity of coil pairs, or a coil configuration in which the numbers of drive coils and sense coils are not equal. The eddy current sensor is able to provide data about the test material, such as material thickness or conductivity, to complement the ultrasonic data or enable auto-setup of the ultrasonic inspection device.

Apparatus and methods for real-time fusion of data acquired using ultrasonic and eddy current area sensors during nondestructive examination. The ultrasonic data is acquired using an array of ultrasonic transducer elements configured to enable the production and display of a C-scan of a small area. The ultrasonic transducer array may be one- or two-dimensional. The eddy current sensor can be a single pair of induction coils, a multiplicity of coil pairs, or a coil configuration in which the numbers of drive coils and sense coils are not equal. The eddy current sensor is able to provide data about the test material, such as material thickness or conductivity, to complement the ultrasonic data or enable auto-setup of the ultrasonic inspection device.

Various aspects include methods of inspecting a substantially round hole in a material. One method can include: feeding a probe axially into the substantially round hole until the probe completely passes through the substantially round hole while the probe is activated; rotating the probe at least ninety degrees around a primary axis of the substantially round hole after feeding the probe completely through the substantially round hole; removing the probe axially from the substantially round hole after rotating the probe at least ninety degrees while the probe is activated; and compiling at least one of eddy current data or ultrasound data about the hole from the feeding of the probe axially into the substantially round hole and the removing of the probe axially from the substantially round hole.

A method of calibrating a sensor array having elements spaced from one another in a first direction, the array defining an array spatial response function, includes: providing a test workpiece having at least first and second calibrated defects spaced apart in the first direction by a characteristic distance such that when the first calibrated surface defect is located at a position corresponding to an array response function maximum, the second calibrated surface defect is located at a position corresponding to an array response function minimum; passing the array across the first and second calibrated surface defects in a direction normal to the first direction and determining a peak sensor signal from at least two of the elements in the array to determine an array spatial response function root mean squared average; and setting a rejection threshold as a predetermined proportion of the array spatial response function root mean squared average.

A detecting device includes a first coil, a third coil, a second coil, and a fourth coil. The first coil generates a first magnetic field on a to-be-measured object. The third coil generates a third magnetic field under the to-be measured object. The second coil generates a second magnetic field. After the fourth coil receives the second magnetic field, a voltage is induced. The induced voltage is amplified by an amplify circuit to drive the third coil. The directions of the currents generated by the first coil and the third coil, respectively, are the same.

Various aspects include methods of inspecting a substantially round hole in a material. One method can include: feeding a probe axially into the substantially round hole until the probe completely passes through the substantially round hole while the probe is activated; rotating the probe at least ninety degrees around a primary axis of the substantially round hole after feeding the probe completely through the substantially round hole; removing the probe axially from the substantially round hole after rotating the probe at least ninety degrees while the probe is activated; and compiling at least one of eddy current data or ultrasound data about the hole from the feeding of the probe axially into the substantially round hole and the removing of the probe axially from the substantially round hole.