Presentation on theme: "ME 271 STRENGTH OF MATERIALS Associate Prof Dr Bülent Ekici."— Presentation transcript:
ME 271 STRENGTH OF MATERIALS Associate Prof Dr Bülent Ekici
Example 1 A torsion bar spring is made of ASTM grade A-48 cast iron is load as shown. The stress concentration factors are 1.7 for bending and 1.4 for torsion. Determine the diameter d for the load P=25 N and T=10 Nm, using a factor of safety n=2.5. (Sut=170 MPa, Suc=650 MPa) Find the diameter
Example 2 A steel rod of diameter d=50 mm (S y =260 MPa S UT =280 MPa S UC =350 MPa) supports an axial load P=50R, vertical load of 0.2R at the midspan of 2m long cylindrical bar and vertical load R acting at the end of an 0.8 m long arm as shown in figure. Given of a factor of safety n=2, compute the largest permissible value of R,
Example 3 Three forces are applied to the machine component ABD, as shown. Knowing that the cross section containing point H has a cross section of 20x40 mm rectangle, determine the principal stresses and the maximum shearing stres at point H.
Example 4 The 6 kN force is vertical and the force P is paralel to the z-axis.Knowing that t all =60 MPa,, Determine the smallest permissible diameter of the solid shaft AD. Strength of shaft is 200 MPa
T=450 Nm M=573.1 Nm Assume no stress concentration