An accelerated corrosion test apparatus that accelerates corrosion of reinforcing steel contained in reinforced concrete specimen having cracking includes: a moisture sensor disposed near the reinforcing steel exposed from a cracked portion of concrete; a weight measuring instrument that measures a weight of the reinforced concrete specimen; and a control terminal that is connected both to the moisture sensor and to the weight measuring instrument and controls a temperature and humidity control device, thereby alternately and repeatedly performing a wetting step of supplying moisture to the inside of a crack in the cracked concrete, and a drying step of removing moisture in the inside of the crack and moisture on the exposed surface of the reinforcing steel, wherein the control terminal terminates the wetting step and starts the drying step when moisture is detected in the moisture sensor, or when change in slope of weight change of the reinforced concrete specimen is detected, after the start of the wetting step.

A system for ultrasonic examination of spot welds comprising a probe, a computer, and a display screen, the computer configured for spot weld analysis by appropriate analytical software, the probe for coupling to a spot weld via a couplant, wherein the probe comprises a two dimensional array of sensors that is each configured to conduct an A scan analysis, thereby providing a color pixel indicating weld quality in terms of parameters selected from the group of size, shape, voids, upper sheet-weld nugget interface strength and lower sheet-weld nugget interface strength, such that the two dimensional array of sensors produces a two dimensional pixilated image indicating the weld quality in terms of selected parameters.

A system for ultrasonic examination of spot welds comprising a probe, a computer, and a display screen, the computer configured for spot weld analysis by appropriate analytical software, the probe for coupling to a spot weld via a couplant, wherein the probe comprises a two dimensional array of sensors that is each configured to conduct an A scan analysis, thereby providing a color pixel indicating weld quality in terms of parameters selected from the group of size, shape, voids, upper sheet-weld nugget interface strength and lower sheet-weld nugget interface strength, such that the two dimensional array of sensors produces a two dimensional pixilated image indicating the weld quality in terms of selected parameters.

An ultrasonic probe comprises a transmitting transducer, a receiving transducer, an absorber, a transmitting and receiving transducer including a transmitting unit and a receiving unit, and a wedge. The wedge includes a first holding part holding the transmitting transducer, a second holding part holding the receiving transducer, an absorber holding part disposed between the first holding part and the second holding part and holding the absorber, and a third holding part disposed on the opposite side of the first holding part from the absorber holding part and holding the transmitting and receiving transducer at an angle allowing ultrasound transmitted from the transmitting and receiving transducer to propagate as surface waves along a surface area of a test object.

An ultrasonic probe comprises a transmitting transducer, a receiving transducer, an absorber, a transmitting and receiving transducer including a transmitting unit and a receiving unit, and a wedge. The wedge includes a first holding part holding the transmitting transducer, a second holding part holding the receiving transducer, an absorber holding part disposed between the first holding part and the second holding part and holding the absorber, and a third holding part disposed on the opposite side of the first holding part from the absorber holding part and holding the transmitting and receiving transducer at an angle allowing ultrasound transmitted from the transmitting and receiving transducer to propagate as surface waves along a surface area of a test object.

The invention discloses a low-frequency electromagnetic detection method for large-scale damage of ferromagnetic materials based on broadband excitation. Detection direction of the magnetic field signal of low-frequency electromagnetic sensor is determined according to the size of ferromagnetic member detection defect; the reference signal and detection signal acquisition position are selected, fix the distance between sensor and tested part, excite a Chirp signal as a broadband excitation signal to perform broadband excitation low-frequency electromagnetic detection; the computer processes collected broadband detection signal; use the difference of Euclidean distance between reference signal and defect detection signal as a defect characterization parameter to obtain the Euclidean distance curve of different depth defects on the upper and lower surfaces of ferromagnetic components with the detection position. Through the analysis and processing of the low-frequency electromagnetic broadband detection signal, the Euclidean response signal and reference signal under broadband excitation are used to characterize the change of material damage degree, which can effectively reduce the influence of magnetic field skin effect, and is beneficial to the effective characterization of the upper and lower material surface defects of at different depths.

The invention discloses a low-frequency electromagnetic detection method for large-scale damage of ferromagnetic materials based on broadband excitation. Detection direction of the magnetic field signal of low-frequency electromagnetic sensor is determined according to the size of ferromagnetic member detection defect; the reference signal and detection signal acquisition position are selected, fix the distance between sensor and tested part, excite a Chirp signal as a broadband excitation signal to perform broadband excitation low-frequency electromagnetic detection; the computer processes collected broadband detection signal; use the difference of Euclidean distance between reference signal and defect detection signal as a defect characterization parameter to obtain the Euclidean distance curve of different depth defects on the upper and lower surfaces of ferromagnetic components with the detection position. Through the analysis and processing of the low-frequency electromagnetic broadband detection signal, the Euclidean response signal and reference signal under broadband excitation are used to characterize the change of material damage degree, which can effectively reduce the influence of magnetic field skin effect, and is beneficial to the effective characterization of the upper and lower material surface defects of at different depths.

Apparatus and device for testing within a metal pipe are described. The apparatus includes an exciter for generating an electromagnetic (EM) field for exciting a wall of the metal pipe; an extendable and retractable sensor assembly comprising a plurality of sensor bars arranged in an angled manner with respect to an axis of the pipe for sensing residue EM field on a wall of the pipe; a plurality of guide wheel assemblies for supporting and moving the apparatus along the axis of the pipe; and a control unit for recording sensed data from the sensor assembly.

Apparatus and device for testing within a metal pipe are described. The apparatus includes an exciter for generating an electromagnetic (EM) field for exciting a wall of the metal pipe; an extendable and retractable sensor assembly comprising a plurality of sensor bars arranged in an angled manner with respect to an axis of the pipe for sensing residue EM field on a wall of the pipe; a plurality of guide wheel assemblies for supporting and moving the apparatus along the axis of the pipe; and a control unit for recording sensed data from the sensor assembly.

A method of determining a distance to a discontinuity within an object may include the steps of: a) generating a continuous, frequency modulated input signal having a predetermined frequency range and a frequency ramping speed using a signal generator and splitting the input signal into at least a test signal and a reference signal; b) generating an input sound wave based on the test signal and continuously introducing the input sound wave into the object using a transmitter and simultaneously receiving a reflected sound wave reflected by a discontinuity within the object and generating a corresponding return signal using a receiver; c) determining a frequency difference value based on a comparison of the reference signal and the return signal using a controller; and d) automatically determining a distance from the transmitter to the discontinuity within the object based on at least the frequency difference value and the frequency ramping speed.