A plurality of captured images is acquired while changing a light illumination state. Each captured image is compared with a corresponding reference image to acquire a region where the captured image is darker than the reference image as a dark defect candidate region. From each of a plurality of captured images, a region where the captured image is lighter than the reference image is acquired as a lightness/darkness inverted region. Among the dark defect candidate regions, those that do not overlap by a prescribed criterion or more with any of the lightness/darkness inverted regions are excluded from defect candidates, and then the presence of a defect is acquired on the basis of the defect candidate regions. This suppresses over-detection of defects arising from, for example, grime on the surface during external appearance inspection.

A plurality of captured images is acquired while changing a light illumination state. Each captured image is compared with a corresponding reference image to acquire a region where the captured image is darker than the reference image as a dark defect candidate region. From each of a plurality of captured images, a region where the captured image is lighter than the reference image is acquired as a lightness/darkness inverted region. Among the dark defect candidate regions, those that do not overlap by a prescribed criterion or more with any of the lightness/darkness inverted regions are excluded from defect candidates, and then the presence of a defect is acquired on the basis of the defect candidate regions. This suppresses over-detection of defects arising from, for example, grime on the surface during external appearance inspection.

A plate specimen is extracted from a qualified HIC resistant material having a Heat number. The plate specimen is supported on a female die of a guided bend system and a force is applied with a male die of the guided bend system to a predetermined middle portion of the plate specimen to develop a U-shaped bent portion in the plate specimen. A curved sample is extracted from the predetermined middle portion having the U-shaped bent portion, the curved sample simulates a cold forming ratio of a line pipe having a particular pipe diameter that is to be subsequently manufactured from the qualified Heat number. A standardized HIC test on the extracted curved sample. Respective values of Crack Length Ratio (CLR), Crack Sensitivity Ratio (CSR) and Crack Thickness Ratio (CTR) are calculated for the curved sample subsequent to the standardized HIC test on the curved sample. The qualified Heat number is validated for manufacturing the line pipe having the particular pipe diameter in response to determining that the calculated respective values of CLR, CSR, and CTR not greater than the corresponding predetermined maximum threshold values for the CLR, CSR, and CTR.

To provide a corrosivity evaluation device that quantitatively evaluates corrosivity that represents an extent to which metal is corroded by an environment. A corrosivity evaluation device evaluates corrosivity that represents an extent to which metal is corroded by an environment, the device including: an electrode unit containing at least one type of the metal by being placed in the environment; a measurement unit adapted to measure a corrosion rate of the metal or a value related to the corrosion rate of the metal during one cycle of change in water content of the environment, the measurements being taken from the one cycle of change; and a calculation unit adapted to calculate a corrosion amount of the metal or a value related to the corrosion amount of the metal from the value measured by the measurement unit.

To provide a corrosivity evaluation device that quantitatively evaluates corrosivity that represents an extent to which metal is corroded by an environment. A corrosivity evaluation device evaluates corrosivity that represents an extent to which metal is corroded by an environment, the device including: an electrode unit containing at least one type of the metal by being placed in the environment; a measurement unit adapted to measure a corrosion rate of the metal or a value related to the corrosion rate of the metal during one cycle of change in water content of the environment, the measurements being taken from the one cycle of change; and a calculation unit adapted to calculate a corrosion amount of the metal or a value related to the corrosion amount of the metal from the value measured by the measurement unit.

Apparatus and methods for detecting flaws in objects comprised of ferromagnetic materials are disclosed. A wireless energizing unit is disclosed that includes an array of permanent magnets is used to induce a magnetic field into the objects and transducers are configured to detect a magnetic flux property in the presence of a flaw in the object. Embodiments that are configured to be clamped over the object are also disclosed. In addition, methods for retrofitting EMI detection systems with a wireless energizing unit are disclosed.

Apparatus and methods for detecting flaws in objects comprised of ferromagnetic materials are disclosed. A wireless energizing unit is disclosed that includes an array of permanent magnets is used to induce a magnetic field into the objects and transducers are configured to detect a magnetic flux property in the presence of a flaw in the object. Embodiments that are configured to be clamped over the object are also disclosed. In addition, methods for retrofitting EMI detection systems with a wireless energizing unit are disclosed.

An acoustic field diffusion type electromagnetic acoustic transducer with improved periodic permanent magnets is provided, which includes periodic permanent magnets, a transducer framework, improved racetrack shaped coils and a transducer connector.

An acoustic field diffusion type electromagnetic acoustic transducer with improved periodic permanent magnets is provided, which includes periodic permanent magnets, a transducer framework, improved racetrack shaped coils and a transducer connector.

The present invention provides a highspeed advanced system to identify and classify the area of anomalies in a railroad rail. This is achieved by using a novel linear array solution that employs parallel transmission of an ultrasonic beam and the use of a virtual synthetic aperture to receive reflected echoes. This integrated system has the capability to locate and classify near surface horizontal defects at speeds more than 40 km/h and at the same time maintaining a constant pulse density of at least 4 mm or less per incremental longitudinal movement.