PNC In-sodium hydrogen meter type-II (Separation type of dynamic and static chambers); Studies of small leak sodium water reactions (15)

Kanegae, Naomichi*; not registered; Daigo, Yoshimichi; not registered; not registered

Seven PNC Type In-Sodium Hydrogen Meter Type-II were designed and manufactured to confirm that these meters will be applicable to the "MONJU" plant, and they have been installed and operated without any troubles in several testrigs of O-arai Engineering Center, Power Reactor & Nuclear Fuel Development Corporation. These meters were improved from the Type-I reported previously, and a new vacuum system named as "Separation Type of Dynamic and Static Chamber" was developed and applied to the Type-II. In this new system, the dynamic and the static chamber are separated from each other in the vacuum system, so that the operation method become very simpler and it becomes possible to calibrate these meters with more accurately and shorter time. This paper explains the basic design specifications, the detail constructions and the test results of in-sodium tests including the calibration and the response characteristics in case of sodium-water reactions were occured. The following results were obtained. (1)The separation type of dynamic and static chamber is effective to simplify the operation method and to improve the accuracy of calibration of hydrogen meter. (2)The optimum design method of hydrogen meter reported preveously was established by several experiences of designing, manufacturing and operating of the Type-II and also the Type-I. (3)Several infomations applicable to the hydrogen meter of the MONJU plant were obtained, and a prospect that this Type-II hydrogen meter will be able to be used in MONJU plant was obtained. Now, long term operation test in sodium is under conducting for confirming life time or characteristics of operation time dependency of the Type-II meters in O-arai Engineering Center.