Hitachi, Ltd.

Hitachi-ge Nuclear Energy, Ltd.

Hitachi Engineering Services Co., Ltd.

Hitachi Engineering Co., Ltd.

Hitachi Nuclear Engineering Co., Ltd.

Masahiro Koike

Tetsuya Matsui

Fuminobu Takahashi

Isao Yoshida

Akira Nishimizu

Yoshio Nonaka

Yoshinori Musha

Kazuhiro Suzuki

Yutaka Suzuki

Naoyuki Kono

Atsushi Baba

Satoshi Ogura

Mitsuru Odakura

Kojirou Kodaira

Kenji Kumasaka

Katsumi Isaka

Kenji Tayama

Yuuji Adachi

Hideki Inoue

Izumi Yamada

Masahiro Tooma

Motoyuki Nakamura

Yoshiaki Nagashima

Minoru Ootaka

Kazunori Koga

Akihiro Taki

Masahiro Hiratsuka

Yosinori Musha

Shuuji Kamimoto

Shinji Naito

Tsukasa Sasaki

Hiroyuki Nakano

Makoto Nagase

Shunsuke Uchida

Hajime Umehara

Kazuo Takaku

Masahiro Miki

Akinori Tamura

Toshiyuki Sawa

Haruo Fujimori

Yasuaki Kageyama

Takaharu Fukuzaki

Yoshihiro Michiguchi

Masami Sukeda

Toshiyuki Furukawa

Hirofumi Ouchi

Sigeru Kajiyama

Naoyuki Kouno

Kenichi Otani

Makoto Senoo

Masafumi Imai

Soshi Narishige

Kenichi Fujiwara

Yoshiharu Abe

Yuuichi Narumi

Norihiro Watanabe

Shinya Odajima

Taro Ikezumi

Hideo Tanahashi

Kazutoshi Ikeda

Hirokazu Adachi

Takao Shimura

Chihiro Matsuoka

Masao Sato

An ultrasonic inspection system includes an ultrasonic sensor and a control device. The ultrasonic sensor has a piezoelectric element that transmits and receives ultrasonic waves and plate portions and that are arranged so as to contact an upper surface of the piezoelectric element and have different thicknesses. The control device acquires a propagation time of a reflected wave reflected on an upper surface of the plate portion, calculates a sound velocity of the plate portion using the propagation time of the reflected wave and a thickness of the plate portion, and corrects a sound velocity of a pipe and acquires a sound velocity of the plate portion based on the calculated sound velocity. In addition, the control device acquires a propagation time of a reflected wave reflected on an upper surface of the plate portion, and calibrates a time axis based on the propagation time of the reflected wave, a thickness of the plate portion, and the sound velocity of the plate portion.

Ultrasonic inspection system

A heat-resistant ultrasonic sensor forms a piezo-electric ceramics film with a thickness of 0.5 mm or smaller and a Curie point of 200&#xb0; C. or higher on a flexible metal plate. A thin metal film that is an electrode is attached to a top surface of the piezo-electric ceramics film and a metal wire mesh covers the thin metal film and is attached to a top surface of the thin metal film. A core of a heat-resistant coaxial cable is connected to the metal wire mesh at a connection point. The heat-resistant coaxial cable is fixed to the thin metal plate with a metal fixing member that is a ground portion. An electric insulating cover is attached to the thin metal plate and covers the piezo-electric ceramics film, the thin metal film, the metal wire mesh, the connection point, the fixing member, and the core of the coaxial cable.

Heat-resistant ultrasonic sensor and installation method thereof

Vibration of a jet pump installed in a reactor pressure vessel of a boiling water reactor is monitored. Ultrasonic waves are transmitted from an ultrasonic sensor installed on an outer surface of the reactor pressure vessel toward a throat and a diffuser of the jet pump. When the ultrasonic waves reach respective outer surfaces of the throat and diffuser, reflected waves are generated at the respective outer surfaces. The ultrasonic sensor receives those reflected waves. The ultrasonic signal process section obtains a distance in the horizontal direction between the throat and the diffuser based on a time difference of the reflected waves reflected from respective reflection surfaces of the throat and diffuser and a sound speed in reactor water in the neighborhood of the throat and diffuser. A relative vibration is obtained based on the change with time of the distance.

Nuclear reactor vibration monitoring apparatus and method of monitoring nuclear reactor vibration

A jet pump beam (hereinafter, referred to as a beam) is fitted into a pair of projecting portions installed to a transition piece, and after the beam is arched, a beam bolt engaged with the beam is tightened. An end of the beam bolt comes in contact with a top surface of an insert member fitted into an elbow disposed between the pair of projecting portions. An ultrasonic sensor head is fixed to the beam bolt, and ultrasonic waves are sent to the beam bolt from the ultrasonic sensor in the ultrasonic sensor head. An ultrasonic measuring apparatus obtains echo intensity of each of reflected waves generated at the end of the beam bolt and a bottom surface of the insert member, and based on the echo intensities, an echo intensity ratio R is calculated. The installed state of the beam is checked using the echo intensity ratio R.

Method of checking installed state of jet pump beam

In an ultrasonic inspection method or ultrasonic inspection system in which an ultrasonic wave is propagated to an test object via a medium such as a liquid or a gas, an incident position of the ultrasonic wave is accurately and reliably identified. In an ultrasonic inspection method based on an immersion technique, an optical irradiator is mounted on an ultrasonic wave transmitting/receiving unit, an optical marker is irradiated from the optical irradiator to the test object, and an irradiated position of the optical marker is imaged using imaging equipment in order to perform inspection.

Ultrasonic inspection system and ultrasonic inspection method

The surface length of a metal subject to be inspected is evaluated by detecting an eddy current without using a combination of a scale and visual or liquid penetrant inspection. An exciting coil and a detecting coil are scanned above the subject in a length direction. An eddy current detector measures an output voltage corresponding to scanning positions based on an output from the detecting coil. Based on an output voltage distribution curve indicating a distribution of output voltages corresponding to the scanning positions, position information is extracted corresponding to values which are within a differential voltage range and lower by 12 dB than a maximum value of the output voltages on the left and right sides of the distribution. A distance between the positions included in the extracted information is calculated to evaluate the length of a slit which is a defect present on the subject surface.

Method and apparatus for evaluating length of defect in eddy current testing

An eddy current testing method for a turbine rotor including a disc, a plurality of turbine blades disposed along the periphery of the disc, and a plurality of pins for joining a blade fork portion formed on each of the plurality of turbine blades to a disc fork portion formed on the disc, the method including inserting a probe having an eddy current testing sensor into a hole formed through the disc fork portion and the blade fork portion by pulling out one of the plurality of pins in a state that the blade fork portion is still inserted into the disc fork portion; and performing eddy current testing for at least part of an internal surface of the hole by using the probe.

Eddy current testing apparatus and eddy current testing method

An ultrasonic testing apparatus for a turbine fork of a turbine blade joined to a turbine disc, comprising:

Ultrasonic testing apparatus for turbine forks and method thereof

The eddy current testing apparatus includes a probe having an eddy current testing sensor including a pair of eddy current testing coils. The apparatus also includes an eddy current testing flaw detector inputting detection signals from the eddy current testing sensor. The diameter of a magnetic core used in each of the pair of eddy current testing coils is within the range of 0.1 mm to 0.5 mm.

Eddy current testing method

An eddy current flaw detection sensor is provided which can detect a circumferential crack occurring at the deformed portion or peripheral portion thereof of a heat transfer tube with a high degree of sensitivity. Two excitation coilscause eddy current B to flow in the axial direction of a tubular test objectA detection coildisposed between the excitation coilsdetects bypass eddy current D which flows in the circumferential direction of the test objectwhile bypassing a circumferential crack E. For this purpose, the coil axes of the excitation coilsare directed to the radial direction of the cylindrical protection memberand the coil axis of the detection coilis directed to the axial direction of the protection member

Eddy current flaw detection sensor and method

A method of connecting hollow conductors with a brazing alloy employs a measuring mechanismfor measuring a connecting state of a connecting portion after brazing hollow conductors. The measuring mechanism comprises a scannerand a holder, which are separated in advance, so that the mechanism can be installed in a narrow space. A display mechanismdisplays measuring results as tow-dimensional patterns, and the evaluation mechanismevaluate the connecting portions by an area of the defects and an integral length of sound portions. A judgment mechanismevaluates relative relation of the measuring results with causes-and-defects, which are previously stored, and shows the cause of the defect.

Method of evaluating connected portions, method of connecting electrical winding conductors and apparatus therefor

An eddy current testing probe has a flexible substrate adapted to face to a surface of a test article, a plurality of coils which are fixed to the flexible substrate and energized one of which is capable of being changed sequentially, a pressing member for pressing the substrate toward the test article, an elastic member arranged between the substrate and the pressing member, and a movement limiting member for limiting a movement of the pressing member toward the test article.

Eddy current testing probe and eddy current testing apparatus

A nondestructive inspection apparatus using a guided wave having waveform forming part that form a transmission waveform; a transmitting element for generating a guided wave within an object under inspection; a receiving element for receiving a reflection wave of the guided wave from an inspection region of the object under inspection; an analyzing element for outputting inspection information which is acquired based upon the reception waveform of the reflection wave received by the receiving element; and a display for displaying the inspection information.

Nondestructive inspection apparatus and nondestructive inspection method using elastic guided wave

In order to make it possible in ultrasonic flaw detection to generate ultrasonic waves containing a main beam only by use of an array probe and clearly identify a defect in a specimen by use of images, an element pitch P (the distance between centers of adjacent ultrasonic transducer elements in the array probe) is set longer than &#xbc; of the wavelength of longitudinal waves generated by the ultrasonic transducer elements and shorter than &#xbd; of the wavelength and reception signals up to time corresponding to the sum of wall thickness round-trip propagation time for longitudinal waves and wall thickness round-trip propagation time for shear waves in the specimen are displayed.

Ultrasonic flaw detecting method and ultrasonic flaw detector

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Hitachi, Japan

Masahiro Koike