Among the fire protection measures in nuclear power plants, the fireproof performance of the fireproof partition installed for system separation is required to satisfy the fire endurance test based on the Building Standard Law. In this time, we report on the result of examining the specification of the fireproof material and the attachment method to the cable tray etc. For the fireproof partition (1 hour fireproof) installed in the cable tray that satisfies the above requirements....
英字タイトル:
Examination of 1 hour fireproof specification of cable tray

ECCS strainer for Hamaoka NPP employs cassette type. At the time of severe accident, it is necessary to take into consideration the chemical debris which has not been considered in BWR so far, in order to carry out pH control in the reactor containment vessel. In this paper, we report the results of closed vertical pipe loop test on the evaluation of the ECCS strainer head loss when considering the chemical debris in addition to the debris such as coating generated at the time of severe accident....
英字タイトル:
Evaluation of ECCS strainer head loss caused by debris generated at the time of severe accidents.

Cable pit under the floor of the main control room of the nuclear power plant is structured as a small section so as to physically separate cables with different safety classifications. This time, a part of cable pit under the floor, which is a narrow and complicated structure, was mocked up and a test was conducted assuming the occurrence of fire at various places in the cable pit. Experiments confirmed the fluidity of smoke and fire extinguishing performance (diffusion and retention state of extinguishing...
英字タイトル:
Consideration of fire extinguishing system inside cable pit under main control room

In order to improve the operational reliability of automatic closure system(hereinafter referred to as "flap gates") used at air conditioning openings of buildings as a measure to protect Hamaoka NPP against tsunami, outdoor exposure test of actual equipment and components , And grasped the deterioration tendency. By making use of the exposure test results in maintenance, we were able to set up a reasonable and appropriate maintenance cycle and to enhance the safety of the Hamaoka NPP. ...
英字タイトル:
Degradation characteristics of flap gate under outdoor environment

The regulatory standards related to nuclear energy that have been enforced since the Great East Japan Earthquake require equipment that is important for safety against tsunami to maintain its integrity. However, at present there is no systematization of impact assessment methods for equipment that is important for safety regarding the collision of the tsunami drifting object. Therefore, in this research, a free fall test that simulates a collision with equipment that is important for safety (pipe) by the ts...
英字タイトル:
Study on the equipment integrity assessment at the time of a drifting object collision

Nuclear power plants are required not to lose safety functions against assumed natural phenomena as damage prevention from external impact. Among possible natural phenomena, it is known that blockage of the intake filter by volcanic ash occurs due to the volcanic effect. Therefore, we are investigating a volcanic ash removal system that uses a metal filter that can remove volcanic ash before the intake filter and supply clean air....
英字タイトル:
Examination of volcanic ash removal system using metal filter

The water of Suppression pool at severe accident has become a hot, high chloride ion concentration and strong alkaline because of exhaust of the reactor heat, the melted cable, and pH controller. The equipment using the water has wetted part made stainless, therefore there is a possibility that SCC because of chloride ion occurs this wetted part. However, alkaline environment may reduce a possibility the SCC although poor knowledge. As such we examined the effect of structural material in a hot, high chlori...
英字タイトル:
Effect assessment of structural material in a hot, high chloride ion concentration, and strong alkaline environment