Seismic Analysis for SEC Drum-Shaped Filter of 1000 MW Nuclear Power Plant

SEC drum-shaped filter structure in 1000 MW nuclear power plant was seismic analyzed by the seismic analysis method of response spectrum and the natural modes of each structure order combined using SRSS and the curves,and taking the amplify coefficient of several seismic waves as the input seismic load.The calculation results show that the maximal response for drum-shaped filter stress was 69.75 MPa at the connection between the main shaft and the A main spoke;the maximal response for displacement was 12.50 mm at the end of the main cross-beam.The strength meets the seismic requirement when checked by the third strength theory,but the limit of side sealing gap was 12 mm that did not meet the seismic requirement when the response value was bigger than the limit.To improve Seismic level of the drum-shaped,the side sealing gap should be increased.