HYDRAULIC SYSTEM FOR BOTTOM-MOUNTED SECOND SHUTDOWN DRIVE MECHANISM

The present invention relates to a hydraulic system for bottom-mounted second shutdown drive mechanism. The hydraulic system can improve space availability according to the installation of a bottom-mounted hydraulic system. Approach and maintenance are facilitated when a reactor is stopped. Also, design margin for a bottom-mounted driving device can be improved. The hydraulic system for bottom-mounted second shutdown drive mechanism includes a tank which is installed at the lower part of a bath and stores the water of the bath; a pump which absorbs and pressurizes the water stored in the tank, and supplies the water to a vertical cylinder assembly; and a water-intake line which connects the bath and the tank and supplies the water of the bath to the tank. The hydraulic system having a pressure boundary and a leak tightness boundary is installed in a reactivity control device room located in the lower part of the bath.