JPS56104221A - Water gauge - Google Patents

Abstract

PURPOSE:To check the inflow of the high temperature water in the reference water surface container into the reference water head pipe and to make it possible to detect correctly the water level in the furnace even in an accident by preparing a resistance increasing member in the junction part of the reference water head pipe and the reference water level container. CONSTITUTION:The difference of the static water head between the reference water head 5 prepared in a dry well 11 inside the storage container 10 and the water head at the measuring point 7 inside of the reactor pressure container 1 is measured by the differential pressure convertor 6 to find a water level and in the junction part 12 of the reference water head pipe 8 of the water gauge of the reference water level container 3 an orifice 13 is fixedly set. In case an accident is occured in the reactor the pressure both inside of the reactor and in the reference water level container 3 is reduced, the vaporization from the reference water level is increased to intensify the water movement. Accompanied therewith the high temperature water in the reference water level container 3 enters the reference water head pipe 8 but the orifice 13 increases the drift resistance to limit the volume of inflow making the density fluctuation caused by the increased temperature of the reference water head water negligible.