Hitachi, Ltd.

Babcock-hitachi Kabushiki Kaisha

The Tokyo Electric Power Company, Incorporated

Chubu Electric Power Company, Inc.

The Chugoku Electric Power Co., Inc.

Tohoku Electric Power Company, Inc.

Sakae Sugiyama

Makoto Senoh

Fumio Tomizawa

Masanori Suzuki

Kimio Kanda

Sigeru Kajiyama

Hiroyuki Takeda

Takao Sato

Yoshiaki Ichikawa

Tomiharu Yoshida

Hiroshi Kamimura

Kenji Tsuchita

Satoshi Ogura

Takashi Omori

Kazunori Koga

Katsumi Kawai

Izumi Kobayashi

Masayoshi Sasaki

Ichio Iseki

Yohsuke Ojiri

Kunio Kudo

Mitsuyuki Oda

Akira Kobana

Akihito Sekido

Hiroyuki Okajima

Remote manipulation method and system of the master-slave type in which an operation procedure plan is prepared for defining each of a sequence of pieces of work as being performed by manual operation or automatic operation at least on the basis of information on the level of skill of a human operator and the sequence of pieces of work is performed in accordance with the plan, whereby work can be done efficiently with human operator's skill taken into consideration.

Method and apparatus for master-slave manipulation supplemented by

A method of and apparatus for determining a position of a working original point at which working characteristics of a multi-joint manipulator are at optimum. According to the method and apparatus, a working point at which a hand mounted on the multi-joint manipulator works and a workspace needed for the work are assigned. Subsequently, a set of positions of the working original point of the multi-joint manipulator at which the hand may reach the workspace is calculated. Also, values of evaluation functions representative of preference of the working characteristics of the multi-joint manipulator are calculated with respect to the respective positions of the set. Then, the values of the evaluation functions are compared with each other, thereby selecting the position of the working original point at which the working characteristics are at optimum.

Method of an apparatus for determining working original point for

Equipment to measure flaws in an object using an eddy current. According to this equipment, attention is given to a relation between the amplitude of signal detected when the eddy current probe is scanning and the position of the eddy current probe, and the size of flaw is measured based upon the fact that scan distance of probe in which flaw detection signals of greater than a predetermined threshold value are obtained, is subject to change depending upon the depth of penetration of eddy current.

Flaw size measurement equipment using eddy currents

A trackless scanner for examination of pipings comprises an annular base removably mountable to a plant pipe to be examined, and a plurality of drive wheels for running supported on the base and being in contact with the plant pipe. Each of the drive wheels is associated with a sensor for detecting an angle which the annular base makes when it turns circumferentially of the pipe, a mechanism responsive to a detection signal from the sensor to control the axial running of the drive wheel for running, and a sensor for detecting a curvature of the pipe.

Trackless scanner

An ultrasonic flaw detecting technique in which reflection echoes of ultrasonic waves transmitted from a plurality of vibrator elements are received, and a composite signal obtained by composing the reception signals is supplied to a composite signal reception processing circuit. A method and an apparatus in which the existence of the composite signal is detected at a first time point at which the composite signal based on the reflection echoes from an inspection target in a main lobe can be detected and at a second and a third time point which are in advance of and later than the first time point respectively and at which the composite signal based on the reflection echoes from an inspection target in the main lobe can not be detected, so that when the existence of the composite signal is detected only at the first time point, it is determined that the composite signal is that based on the reflection echoes from the inspection target.

Method of selecting composite reception signal in ultrasonic inspection

A method of detecting a leakage of fluid is disclosed, in which a leaking sound, which is produced when the pipe is broken and propagates through the pipe, is detected by a couple of acoustic sensors mounted to a pipe through which fluid flows at portions separated from each other with a proper distance, the amplitudes of a plurality of different frequency components extracted from the output signals of the acoustic sensors are obtained and then a leaking location of fluid in the pipe and a leaking amount of fluid are determined on the basis of these amplitudes.

Method of detecting a leakage of fluid

In ultrasonic flaw inspection for determining the size of a flaw by emitting an ultrasonic wave to a subject via a probe and receiving an ultrasonic echo from said flaw existing inside said subject, changes in the propagation distances of the ultrasonic echoes before and after movement of said probe through a micro-small distance are compared with each other and the ultrasonic echoes are determined to result from the same flaw if the change width falls within a predetermined value determined by the angle of incidence of the ultrasonic wave and the directional angle.

Ultrasonic method of determining nature of flaws by incremental scanning

A method of inspecting non-destructively a specimen for examining the presence or absence of a defect in the specimen, in which an ultrasonic wave is emitted from a probe and a reflected wave from the specimen is received by the probe whose output signal is processed to determine the presence or absence of the defect. The signal processing includes steps of extracting characteristic parameters from a frequency spectrum of the ultrasonic echo and comparing the extracted parameter with corresponding experimentally or theoretically determined values. The invention makes it possible to automatically determine discriminatively whether the reflector of the ultrasonic echo is a configured portion, a weld boundary or a defect of a specimen to be inspected.

Non-destructive inspection by frequency spectrum resolution

An annular guide rail is detachably mounted in enclosing relation around a tubular member of piping to be probed for any flaws that might be present therein, and a flaw detecting unit, a circumferentially driving unit and an axially driving unit are movably arranged on the annular guide rail and interconnected by connecting means. The flaw detecting means includes an arm movable axially of the tubular member and supporting ultrasonic flaw detecting means. The circumferentially driving unit includes first driving means for moving the flaw detecting unit, circumferentially driving unit and axially driving unit circumferentially along the guide rail. The axially driving unit includes second driving means for moving the arm axially of the tubular member. A transmission mechanism is provided for transmitting the operation of the second driving means to the arm.

Ultrasonic probing apparatus

A ultrasonic flaw detector driving apparatus including a driving apparatus which is equipped with an arm mounted respective side faces of a main frame of the ultrasonic flaw detector driving apparatus so as to allow the arms to move into an open and closed position. A resilient member provides a force which acts on the respective arms in such a direction so as to urge the arms into the open position. A ratchet prevents the arms from being opened by the resilient member as teeth engage with a pawl in a stepwise manner. Rollers are rotatably mounted to a tip of the respective arms and are in rolling contact with the guide rail on which the driving apparatus travels. The arms are moved to the open for mounting the driving apparatus to the guide rail and thereafter the arms are moved to the closed position. Thus, the main frame of the driving apparatus can be position movably fixed onto the guide rail.

Ultrasonic flaw detector driving apparatus

A plurality of local power range monitors are provided in the core of a nuclear reactor and the total output of the reactor is obtained from the outputs of the monitors. The output of the reactor, if it reached its equilibrium state, will normally keep a constant value, but after the load is changed, the output is also varied by the influence of the neutron absorbing property of the fission products generated as a result of the load change, and especially after the reactor output has been increased, it is spontaneously increased over its setting value to cause the reactor to overheat. The minimum allowable recirculating flow which prevents the overheat at a given total output, is obtained on the basis of the total output. If the actual recirculating flow is larger than the minimum allowable flow, the recirculating flow is freely controlled, but if the actual flow is smaller than the minimum value, the control of the recirculating flow is prohibited and the control rods are inserted for the control of the reactor output. The insertion begins with one of the control rods near the local power range monitor whose output is the maximum.

Control system for boiling-water reactor

An apparatus for automatically starting up a nuclear reactor, which causes control rods in the reactor to be withdrawn in the predetermined order according to the signal obtained by adding the heat-up ratio as a compenstory component determined by the reactor pressure to the deviation of the heat-up ratio of the reactor temperature from the predetermined heat-up ratio and which causes the reactor to be subjected to heat-up and pressurization by opening turbine bypass valves when the heat-up ratio exceeds a reference value.

Growing community of inventors

Ibaraki, Japan

Sakae Sugiyama