JOPSS - Search Results

Journal Articles

Rail DRAGON: Long-reach Bendable Modularized Rail Structure for Constant Observation inside PCV

Yokomura, Ryota*; Goto, Masataka*; Yoshida, Takehito*; Warisawa, Shinichi*; Hanari, Toshihide; Kawabata, Kuniaki; Fukui, Rui*

IEEE Robotics and Automation Letters (Internet), 9(4), p.3275 - 3282, 2024/04

https://doi.org/10.1109/LRA.2024.3366022

To reduce errors in the remote control of robots during decommissioning, we developed a Rail DRAGON, which enables continuous observation of the work environment. The Rail DRAGON is constructed by assembling and pushing a long rail structure inside the primary containment vessel (PCV), and then repeatedly deploying several monitoring robots on the rails to enable constant observation in a high-radiation environment. In particular, we have developed the following components of Rail DRAGON: bendable rail modules, straight rail modules, a basement unit, and monitoring robots. Concretely, this research proposes and demonstrates a method to realize an ultralong articulated structure with high portability and workability. In addition, it proposes and verifies the feasibility of a method for deploying observation equipment that can be easily deployed and replaced, while considering disposal.

JAEA Reports

Radiation control on wastes recovery work in wastes storage pit

Ito, Yasuhisa; Noda, Kimio; ;

JNC TN8410 2001-018, 67 Pages, 2001/04

JNC-TN8410-2001-018.pdf:2.96MB

There are waste storage pits where non-radioactive wastes generated from plutonium fuel facilities were stored in JNC Tokai Works. But radioactive wastes were found in one of the pit during wastes arrangement works. Therefore we set the pit temporary controlled area and recovered wastes from it. This report describes the radiation control technique of recovery work in detail.

JAEA Reports

Development of resistance welding process; Manufacture of test specimens for ODS steel strength evaluation

Endo, Hideo; Seki, Masayuki; ; *; *

JNC TN8410 2000-007, 89 Pages, 2000/03

JNC-TN8410-2000-007.pdf:6.28MB

(1)Outline of examination. Various test specimens were made to evaluate and confirm the weld strength properties of the oxide dispersion strengthened (ODS) cladding tube material (martensitic and ferritic steel), which had been manufactured in JFY 1997. The examination consisted of tensile tests (RT,650 $^{circ}$ C, 700 $^{circ}$ C, 800 $^{circ}$ C), internal pressure creep tests, internal pressure burst tests, and a rapid heating burst tests. (2)Examination results. The results of the tensile tests are as follows: (ferritic and martensitic) (a)All test specimens from RT to 700 $^{circ}$ C failed in the tube. The weld zones had not failed. (b)The test specimens at 800 $^{circ}$ C failed in the weld zones. There was little elongation. (ferritic) (a)The weld zone had fine grain structure and carbide precipitates. (martensitic) (a)Carbide had precipitated in the weld zone. From these results, the strength of weld zone decreased extremely at temperatures exceeding the endurance limit (700 $^{circ}$ C) All of the internal pressure burst test specimens and the rapid heating burst test specimens failed in the tube and not the weld zone. (3)The quality assurance method of the test specimens. The weld reliability of the test specimens were confirmed by the process control of the welding conditions, by using control test specimens, and ultrasonic testing. Confirmation of the process control of the welding conditions; current wave, the voltage waveform, the accelerogram, and the displacement ripple in the welding process was recorded to assure an abnormal value had not occurred. (Process control of welding condition) The results the current waveform, voltage waveform, accelerogram, and the displacement waveform were excellent. (test specimens) The weld joint was excellent based on metallography examination. (Ultrasonic testing) The length of the weld joint was measured and found to be adequate. The reliability the weld joint can be assured by using the above-mentioned method.

JAEA Reports

None

PNC TJ1600 98-004, 50 Pages, 1998/03

PNC-TJ1600-98-004.pdf:1.63MB

no abstracts in English

JAEA Reports

None

Ishida, Junichiro; ; ; ;

PNC TN8440 96-008, 183 Pages, 1996/03

PNC-TN8440-96-008.pdf:12.79MB

None

JAEA Reports

None

Tsujimura, Norio; Momose, Takumaro; Shinohara, Kunihiko

PNC TN8410 96-036, 20 Pages, 1996/02

PNC-TN8410-96-036.pdf:0.55MB

None

JAEA Reports

None

PNC TN8440 93-045, 104 Pages, 1993/09

PNC-TN8440-93-045.pdf:2.68MB

None

JAEA Reports

Reports of results of mock-up test concerning the remote piping work system

Tanaka, Yoji*; Nakasawa, Otohiko*; Sugumoto, Hiroshi*; Takeshita, Hiroshi*

PNC TJ8224 92-002, 33 Pages, 1992/03

PNC-TJ8224-92-002.pdf:1.06MB

no abstracts in English

JAEA Reports

Design study of ISI system for MONJU primary cooling piping

; ;

PNC TN9410 91-169, 87 Pages, 1991/08

PNC-TN9410-91-169.pdf:2.32MB

We have been developing a inspection tool in order to apply for ISl of 32B sized elbow piping on MONJU primary cooling circuit. Experiments and examination were carried out on design work to decide the design parameters. We obtained the results as follows, (1)The design parameters of un ultrasonic probe, such as the ultrasonic element's diameter, frequency and refraction angle, were chosen as the most suitable for fraw detection. (2)It was confirmed that the most stable scanning of the scanner was achieved by the control of 3 driving wheels. (3)The scanner could be carried by 2 persons, it's weight was 38kg. (4)The handling mechanism for thermal insulator consist's of three divided piecies and lt's driving source is pneumatic. The conclusions of this study were as follows, (1)An equipments of the volumetric examination for large scale elbow piping was designed, and it could be use at 80 $^{circ}$ C without supplying and collecting apparatus for couplant. (2)This system must be contribute the reduction of human radiation dose.

JAEA Reports