Calculating required diameter of rod to support a given load
Hi!
Trying here to calculate the diameter d required of a length L=800mm solid steel rod, supported at both ends which needs to safely hold W 2000kg (19620N ) at the centre.
Details of the rod ( structural steel ), taken Modulus of elasticity E at 200Gpa and Yield Strength σ at 250Mpa
Using moment of inertia I = (πd^4)/64
Maximum stress σ = yWL/4I. Where y would be d/2 , maximum distance from neutral axis
Messing around with these two equations making d subject, I get;
d = cuberoot( 8WL / πσ ) . Inserting all numbers I got a diameter of 54mm which seems a bit excessive to me? Anything I am doing wrong here? Thanks a lot.