Fatigue life analysis of supercharged boiler based on the design by analysis method

Supercharged boilers are widely used as the core equipment of ship steam-power plants. A 1:1 model is built considering the connection details of tube-tubesheet joints. Furthermore, numerical simulation of stress field and fatigue life based on the DBA method is conducted. The results show that the maximum equivalent stress amplitude of 253.81 MPa appears on the tube-tubesheet joint of the tube plant radiation area. The total stress amplitude is dominated by the thermal stress range. The last calculated permissible number of cycles based on the fourth strength theory is 161,744 times, which is 15.7% higher than the result calculated by the third strength theory. •Full-size supercharged boiler model is established.•Stress analysis is conducted following the ASME design by analysis approach.•Key parameters in fatigue analysis are computed using user defined result function.•Three correction factors involved in the ASME BPVC code are strictly corrected.•The benefit and drawback of two strength-theory-based analysis methods are compared.