Design and draw a cast iron flange coupling for a mild steel shaft transmitting 80 kW at 220 r.p.m. with the following specifications:
Allowable shear stress in the shaft = 40 MPa
Permissible angle of twist < 10 in a length of 20 diameters.
Allowable shear stress in the coupling bolts = 30 MPa.
Rigidity modulus of shaft material = 85 GPa
Allowable shear stress for hub material 15 MPa
You may adopt,
Width of key = 25 mm
Thickness of key = 14 mm
You may also consider that he shaft and key are made of the same material. Four numbers of bolts are to be used in the coupling. Find out the diameter of the shaft required and the main dimensions of the Flanges and the Key. Adopt suitable dimensions.