Problem-1:

A rigid coupling has a bore diameter of 50 mm. Four machined bolts on a bolt circle of 125 mm diameter and fitted in reamed holes. If the bolts are made from the same material as the shaft, with an ultimate tensile strength of 550 MPa and a yield point in tension of 345 MPa, determine the necessary size of bolts to have the same capacity as the shaft in torsion.

Problem-2:

Assume that a flange coupling has the following specifications:Number of bolts: 6.Size of bolts: 12 mm diameterPreloading of bolts: 22 KN in each bolt.Inner diameter of contact: 175 mm.Outer diameter of contact: 200 mm.Speed of rotation of coupling: 300 rpm.Coefficient of friction: 0.15Shaft diameter: 50 mm.Shaft material, annealed steel with an ultimate tensile strength of 586 MPa and a yield point in tension of 310 MPa.The bolts are set in large clearance holes in the coupling.

1)Determine the maximum power capacity based upon friction such that slip occurs between faces of contact.

2)Compare the shaft power capacity with the friction power capacity. Assume steady load conditions and that the shaft is in torsion only.

Figure-2

Problem-3

Set up the equations or relations necessary to determine:

a)the hub diameter DH.b)the web thickness t.c)the flange thickness h.

Problem-4:

A flange coupling connects two 50 mm diameter lengths of commercial shafting. The coupling webs are bolted together with four bolts of the same material as the shaft. The bolts are set in clearance holes. The diameter of the bolt circle is 240 mm and the web thickness is 22 mm.

a)Determine the minimum bolt diameter required transmitting the same torque that the shaft can transmit.

b)What power may be transmitted at 200 rev/min under steady state conditions?