We are developing portable non-destructive testing (NDT) X-ray source with X-band linac and low power magnetron. Now, we start the experiment of electron acceleration and X-ray generation using by 950 keV X-band linac NDT system. The 950 keV X-band linac X-ray generator is under development for corrosion wastage of tubes and condition bas ed maintenance of impeller pumps. However, about 1 MeV X-ray source can be only used for thin tubes of about 20 mm thickness. Therefore, we start to design about 4 MeV X-...
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Development of High Energy X-ray NDT System with 3.95 MeV X-band Linac

We have been developed 9.4 GHz X-Band linac and 250kW magnetron for X-ray nondestructive tes ting system for Condition Based Maintenance (CBM). Our linac's energy is 950 keV, which fits to Japanese regulation to take them to outside of radiation controlled area. This small port able linac enables to diagnosis the moving facility, such as bearing in Nuclear Power Plants....
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Development of 960keV X-Band Linac for Portable Nondestructive Testing System

吉田 光宏 Mitsuhiro YOSHIDA 山本 昌志 Masashi YAMAMOTO 中村 直樹 Naoki NAKAMURA ...
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Portable 950keV X-band Linac X-ray Source for On-site NDT

Neutron diffraction technique is one of prevailing method to measure inner structure of material, such as molecular arrangement and lattice spacing by means of penetration of neutron. In particular the residual stress measurement by neutron diffraction has been developed an d is greatly performed in many research facilities, because the examination of residual stress existing materials is critically important to estimate fatigue of the materials and to maintain structural objects for efficient utilization....
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Measurement of Inner Residual Stress of Bearing by Neutron Diffraction Technique

Our portable X-band (9.3GHz) 950KeV linac has been successfully upgraded. The problems of RF power oscillation , beam current oscillation and reduction and finally lack of X-ray intensity were solved by replacing the axia l coupling cavities with the side-coupled ones. Designed X-ray dose rate of 0.05 Sv/min@lm is going to be achi eved. Length of the accelerating tube is reduced to less than 25 cm. X-ray source part with the local radiation shielding is connected by the flexible waveguide with the box of t...
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Study on Portable X-band 950keV linac X-ray Sourcefor On-site Nondestructive Inspection

We are developing X-ray nondestructive testing (NDT) system using with portable X-band linac. This system uses 2.4 GHz X-band linac and 250 kW magnetron. Our system energy is 950 keV for Japanese regulation. Th erefore we can use it on-site using local radiation protection. We measured electron beam and X-ray. We have started X-ray maging test. We will use this system for condition based maintenance of pump-impeller a t nuclear plants. The linac based X-ray source can generate pulsed X-ray. Therefore we ca...
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Macro Damage Observation of Bearing using Portable X-band Linac Based X-ray Source

可搬型高エネルギーX線源を使用した橋梁内部の複数アングルからの撮像を、「トモシンセシス」と 呼ばれる技術を用いて再構成することで、内部構造の3次元視覚化が可能となる。これにより、橋梁健全性評価システムの高精度化が期待できる。2017 年 6 月と 7 月に実施した実橋梁検査の結果も考察する。 ...
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3D Visualization of Inner Bridge using Portable High Energy X-ray Source and its Valuation

In order to decommission TEPCO Fukushima Daiichi nuclear power plant, the removal of fuel nuclear debris is planned from 2021. It is demanded to grasp nuclear material element contents of the debris remaining inside the accident reactors for the effective and safe removal. Our research team aims to do the on-site analysis of the extracted debris by the Spectral X-ray CT method with the portable X-band (9.3 GHz) 950 keV/3.95 MeV electron linac X-ray sources and GAGG X-ray detector. It is expected to realize ...
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Fukushima Nuclear Fuel Debris Component Analysis by Spectral CT with Portable High Energy X-ray Source

Condition Based Maintenance (CBM) is very important for safety of nuclear plants. We analyze basic experimental data for quantitative lifetime evaluation of bearings. So far the lifetime is guessed by fitting curves for signal out puts from vibration gauges. However data spread of results is rather large depending on the conditions of equipment, operation and environment. We are performing AE-, vibration- and oil-debris- analyses and trying to understand th e fracture status more directly. Further, we newl...
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Strategy on QuantitativeCondition Based Maintenance

Two magnetic methods are proposed for the evaluation of initial degradations of type 304 stainless steel in stress corrosion cracking (SCC). The first one is the measurement of the distribution of chromium depletion by means of a magnetic force microscope (MEM). MEM observations are performed for some samples sensitized in various conditions, and the obtained results coincide with the expected ones from the chromium behavior. Moreover, the phase distributions in the solution-annealed and sensitized states a...
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Evaluation of Initial Degradation in Stress Corrosion Cracking by Magnetic Methods