Question 2 An engineer is asked to design a machine shaft which will be supported in...

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Question 2 An engineer is asked to design a machine shaft which will be supported in bearings 920mm apart. Power is supplied to the shaft through a 440mm diameter pulley running at 620 rpm and located 270mm to the left of the left-hand bearing. Power is transmitted from the shaft through a pitch circle diameter 230mm spur gear pinion located 220mm to the left of the right-hand bearing. The belt drive is horizontal and the two belt tensions are: T1 = 1520N (bottom section to the left) and T2 = 660N (top section to the left). The belt pulley weighs 120kg. The forces on the gear due to the power transmitted are horizontal 1820N (to the left) and vertical 820N (downward). If the solid shaft material has an ultimate shear strength of 430 MPa and ultimate tensile stress is 640MPa, neglecting fatigue factors and using a factor of safety of 6. The modulus of rigidity can be assumed to be 87 GPa. 2.1 2.2 Sketch a neat, labelled diagram of the front and end elevation of the set-up. Indicate all (10) the relevant loads and calculations as they are applied. With reference to the tight and slack side of the belt, explain why you chose the position (2) of placing the slack side. 2.3 Draw a neat fully labelled sketch of the free body and bending moment (show calculations) diagrams for the horizontal plane. (4) 2.4 Draw a neat fully labelled sketch of the free body and bending moment (show calculations) diagrams for the vertical plane. (4) 2.5 Determine the maximum bending moment where the shaft will fail. (5) Question 2 An engineer is asked to design a machine shaft which will be supported in bearings 920mm apart. Power is supplied to the shaft through a 440mm diameter pulley running at 620 rpm and located 270mm to the left of the left-hand bearing. Power is transmitted from the shaft through a pitch circle diameter 230mm spur gear pinion located 220mm to the left of the right-hand bearing. The belt drive is horizontal and the two belt tensions are: T1 = 1520N (bottom section to the left) and T2 = 660N (top section to the left). The belt pulley weighs 120kg. The forces on the gear due to the power transmitted are horizontal 1820N (to the left) and vertical 820N (downward). If the solid shaft material has an ultimate shear strength of 430 MPa and ultimate tensile stress is 640MPa, neglecting fatigue factors and using a factor of safety of 6. The modulus of rigidity can be assumed to be 87 GPa. 2.1 2.2 Sketch a neat, labelled diagram of the front and end elevation of the set-up. Indicate all (10) the relevant loads and calculations as they are applied. With reference to the tight and slack side of the belt, explain why you chose the position (2) of placing the slack side. 2.3 Draw a neat fully labelled sketch of the free body and bending moment (show calculations) diagrams for the horizontal plane. (4) 2.4 Draw a neat fully labelled sketch of the free body and bending moment (show calculations) diagrams for the vertical plane. (4) 2.5 Determine the maximum bending moment where the shaft will fail. (5)