LECTURE2 - Bülent EKİCİ

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ME 271 STRENGTH OF MATERIALS
Associate Prof Dr Bülent Ekici
Example
Example
Example
Example
Example
Example
Example
Example
Example
Example
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 (Sy=260 MPa
SUT=280 MPa SUC=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 tall=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
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