Establishment of effective maintenance method based on the superior inspection technique for the deteriorating hot laboratory exhaust stack

Mizukoshi, Yasutaka; Yasu, Tetsunori

JAEA-Technology 2012-013, 26 Pages, 2012/06

JAEA-Technology-2012-013.pdf:6.74MB

The Materials Monitoring Facility is equipped with an exhaust stack to emit air from a controlled area (the hot laboratory) into the atmosphere. Cracks and exfoliation have been observed for the surface of the exhaust stack, which is made of reinforced concrete and was constructed on the seacoast about 25 years ago, so exposed to a salt-corrosive condition. In order to get details of the present condition of the exhaust stack, an inspection was carried out using an electromagnetic wave radar method and chloride content method. Cracks and exfoliation were observed for the whole stack surface, especially for high positions. Moreover, salt damage was observed for the outer surface of the exhaust stack, and it was estimated that the infiltration of the chloride content was about 17 mm. Based on this detailed inspection of the exhaust stack, maintenance and repair work were carried out.

Development of Material International Rig with Precise Temperature Control in Experimental Fast Reactor JOYO

Miyakawa, Shunichi; Kataoka, H.; Yasu, Tetsunori;

Proceedings of 8th International Conference on Fusion Reactor Materials (ICFRM-8), P. 319, 1997/10

None

Experimental fast reactor "JOYO" operational experience; Summary of register on machinery and tools in '92 '93 and '94

; ; ; ; Yasu, Tetsunori; Morimoto, Makoto;

PNC TN9410 95-243, 48 Pages, 1995/09

PNC-TN9410-95-243.pdf:1.48MB

The Register on Machinery and Tools is used for recording, summarizing, and accumulating the career of operation and maintenance, the operation experiences, and the results of research and development. It has been provided in order to secure equipment maintenance, safety control, and stable plant operation. Arrange and improvement of the Register on Machinery and tools is indispensable for preparing the technical reports (ex. "JOYO" Operation and Maintenance Experience Compile (JOMEC)), and for Job transfer from the person who was in charged of the system. This report summarizes the register from 1992 to 1994, related to the primary sodium purification system, the primary sodium sampling system, the gas chromatography monitor of primary cover gas, the primary argon gas sampling system, the sodium fill and drain system, the primary argon gas system, and the compressed air supply system. The conspicuous contents are as follows; (1)The electromagnetic pump (EMP) in the primary sodium purification system has been impossible to be started several times, because the purification line was blockaded. The EMP was coming back into operation successfully by changing over of the lines, etc. The blockade line was melted by temperature increasing of the flowing sodium at restored EMP. (2)The outlet valve of the primary sodium sampling system did not operate because of broken stem pin. It was repaired. (3)There were movement inferiority of the fore side valve of the dehumidified tower in the compressed air supply system, and damage of control air piping, etc. We successfully kept continuous operation by replacing the damage parts. After that, the fore side valve control unit was renewed in order to cope with superannuating of dehumidified control system. (4)The other systems had been favorably operated without particular trouble.