Question

em 35? ? A cylindrical pressure vessel is constructed from a long, narrow steel plate by wrapping the plate around a mandrel and then welding along the edges of the plate to make a helical joint. The helical weld makes an angle ? 350 with the axial direction. The vessel has inner radius r = 1.8 m and wall thickness 20 mm. The material is steel with E 200 GPa and Poisson ratio 0.3. The internal pressure p = 800 KPa. Calculate a hoop and axial stress on the pressure vessel b) max shear stress (in-plane and out-of-plane) hoop and axial strains a normal stress o, and shear stress r, acting perpendicular and parallel to the welded seam

Answer 1

" d/t = 3.6m/20 times 10^- 3 greaterthanorequalto 20 Therefore analysis is for thin cylinders theta = 35 degree, ri = 1.8m, t = 20 mm E = 2004 pa, M = 0.3, p = 800 kpa Hoop stress, sigma_h = pd/2t = 800 times 10^3 times 3.6 times 10^3/2 times 20 = 72 MPa axial stress, sigma_l = pd/4t = 36 MPa Max in - plane shear stress: (T_max)_inplane = [sigma_h - sigma_l/2] = [72 - 36/2] = 18 MPa Max out - plane shear stress (T_max)_out plane = max {