In recent years, the inspection of pipes is being carried out by using inspection techniques which employ ultrasonic and eddy current testing, endoscope (CCD cameras or optical fiber). Currently, the inspection devices can be performed only a visual check of the pipes. In case of a damage, they cannot be repaired. In such case, the damaged portion has to be excluded or the pipe has to be replaced. The authors develop a laser processing head comprising an optical fiberscope. It is capable of inspection...
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Development of a laser processing head for the inspection and repair of damages inside of a half-inch pipe

A prototype of maintenance machine for heat exchanger tubes was developed. It was based on the bench top size device which had been specially designed to have dual functions for fiber inspection and laser cladding in JAEA. A laser processing head was improved mechanically in 2 motions of axial translation and circumferential rotation to insert the heat exchanger tubes. ...
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Development of Maintenance Machine for Heat Exchanger Tubes by Laser Technology

New maintenance technique was proposed using a hand-held laser torch for aging chemical plants and power plants. The hand-held laser torch was specially designed to be able to access limited tubular space in various cases. A composite-type optical fiberscope was composed of a center fiber for beam delivery and surrounded fibers for visible image delivery. Laser irradiation on a work pieces with the best accuracy of filler wire was carried out. And, we found that the optimized wire-feed speed was 2 mm/...
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A Study of Cladding Technology on Tube Wall Surface by a Hand-held Laser Torch

For decommissioning of the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Company Holdings, Incorporated, we are now developing remote laser diagnostic techniques for integrity evaluation of support structures. Ultrasonic waves were induced on a sample by an impact laser. The waves propagating through the sample were detected with a laser Doppler vibrometer using a measuring laser. This technology enables remote, non-contact diagnosis....
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Characteristics of structures using laser diagnostic techniques

We are developing the inspection technology for laser micro spot welding. Butt welding for the inner wall of heat exchanger tubes were successfully carried o ut by a composite-type optical fiber scope. The related technologies are the f ollowing : Rapid inspection by Eddy Current Testing Fiber endoscope observation 3 Synchrotron X-ray absorption contrast method. These technologies are versatile to be applied in maintenance for industrial production plants....
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Development of Inspection Technology for Laser Welding Section

Laser thermal processing was applied to robotic systems. For the narrow limited space like a 1-inch diameter tube, a compact laser processing head successfully observed the heat exchanger tube inner wall and welded a crack gap. A compact air cooled fiber laser was able to heat an inner wall through a delivery optical fiber. A filler wire feeder for laser cladding was also tested. A compact maintenance robot for petrochemical industrial plants was demonstrated....
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Development and Deployment of Maintenance Robot with Laser Thermal Processing

A hybrid optical fiber scope and a laser processing head were combined with an eddy current testing un it for the inspection and repairing for Fast Breeder Reactor's heat exchanger pipes. The project propo ses an effective cost reduction method for maintenance of FBR by extension of the heat exchanger's lif etime. By the end of March 2010, a prototype probing system for heat exchanger pipes will be completed....
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Development of Inspection and Repairing Technology for FBR Heat Exchanger Pipes

In order to maintain FBR heat exchanger tubes, a new probe system was designed. A coupling u nit and operational software are key components in the second year. The coupling unit to com bine a high energy laser beam and optical fiberscope images was developed. The operational s oftware successfully controlled an eddy current testing device and a laser processing head....
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Development of Inspection and Repairing Technology for FBR Heat Exchanger tubes (II)Preparation of Operation Software and Performance Check

Fine magnetic particles having UV fluorescence are commonly used in magnetic crack detection technique. Stress corrosion cracking sometimes happens in nuclear power plants. To apply this technique to maintain the heat exchanger tubes, it is desired that these particles has performance to be collected with ease. To c ollect these fine magnetic particles from millimeter size crack depth, a chemosynthesis technique to produce the micro capsules successfully produced hundreds micron sized capsules containing t...
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A fluorescent micro capsule manufacture of magnetic particle testingfor advanced inspection technique of heat exchanger tube

本報は、POPI方式の高感度地震計の実用化を目的として、その実施試験として原子炉格納容器、石油貯蔵タンク、化学プラント反応容器などタンク形状の構造体の振動特性の報告である。試験場所として、日本原子力研究開発機構の楢葉遠隔技術開発センター（以下NARRECと略記）を活用し、タンク形状構造体としてNARRECに設置された水中ロボット操作用試験水槽を使用した。また、地震計設置にあたって１F設置のために開発してきた専用ロボットによる設置試験も行った。 ...
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Observation of Vibration Characteristics of a Cylindrical Water Tank by a Phase-shifted Optical Pulse Interference Sensor