STATIC, FATIGUE AND CREEP ANALYSIS OF BOILER SHELL WITH CIRCUMFERENTIAL RIVETED JOINT

Abstract

Boilers and pressure vessels with riveted joints are used to contain pressurized fluids and are subjected to complex loads under static, dynamic and creep situations. Pressure vessel failure happens both circumferentially and longitudinally. Circumferential riveted joints are critical to the design of pressure vessels because the circumferential stress is double the longitudinal stress. Boiler shell with circumferential riveted joints is studied at pressures between 2.5 MPa and 5 MPa for structural analysis. Boiler shell with circumferential riveted joints is studied at pressures 2.5 MPa and varying temperature (300 °C, 400 °C, and 450 °C) for creep analysis. The riveted joint was created with SolidWorks software and Ansys software. The proposed joint is investigated to examine how structural steel, titanium alloy, and nickel-cobalt-chromium alloy affect the vessel's performance. The results are displayed, and a comparison is made in order to determine which material is the best. Static results indicate that Boiler shell joints of nickel cobalt-chromium alloy have a smaller total deformation (0.067mm) and lower Von-misses stress (63.37MPa) than structural steel and titanium alloy at an internal pressure (2.5 MPa). The Maximum shear stress of titanium alloy (30.63 MPa) shows better result as compared to Structural steel (33.52 MPa) and Nickel-Cobalt-Chromium alloy (34.11 MPa). Data for fatigue life, damage, safety factor and sensitivity for candidate materials are provided by Ansys software. The findings demonstrate that the boiler shell with circumferential riveted joint of Titanium alloy has a good fatigue life, low fatigue damage, and a high safety factor at high internal pressure when compared to the circumferential riveted joint of structural steel, Nickel cobalt-chromium alloy. The final result shows that selected materials will survive and function well, while titanium alloy and nickel-cobalt-chromium alloy surpass structural steel. From the Creep analysis equivalent creep strain of structural steel at constant load (2.5MPa) and varying temperature (300 °C, 400 °C and 450 °C) are 0.0016895, 7.2834e-6, and 6.2525e-5 respectively. The finding demonstrates that the best load range for greater creep life of structural steel was shown to be 2.5 MPa, and the optimum temperature range was discovered to be 4500 C. The final result demonstrates that as the temperature is gradually increased to its maximum limit, the creep strain rate of the specified material (structural steel) increases or decreases