(50 pts.): In the system shown below, shaft AC is to rotate at n = =...

 

 

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(50 pts.): In the system shown below, shaft AC is to rotate at n = = 600 rpm and transmit torque T = 2000 lb.in to the machine at full load operation. The gears used in the system are spur gears having pressure angle 20, number of teeth of gear D is 40 teeth, and of gear B is 20 teeth. Assuming no power losses, then: (a) Determine the minimum diameter of shaft AC, knowing that shaft AC is to be made of hot rolled steed having yield strength = 48 kpsi, ultimate strength = 75 kpsi, fully corrected endurance limit Se = 26 kpsi, and the estimated fatigue stress concentration factors at shoulders in bending and torsion are respectively K = 2.1 and Ky, = 1.9. Use DE-Soderberg method with fatigue factor of safety n = 1.5. (b) Determine the rotational speed of the driving sprocket Q in units of rpm, knowing that the speed ratio of the sprockets is to be no lng = 2. Note that Qis the smaller sprocket as shown in the figure.. (c) Select an appropriate double strand sprocket-chain drive to be used as shown in this system. You need to identify (1) chain number, (2) number of teeth on driving sprocket, (3) number of teeth on driven sprocket, (4) length of the chain in pitches. Motor 7.5 in D 30 in 4 in 12 in T," (50 pts.): In the system shown below, shaft AC is to rotate at n = = 600 rpm and transmit torque T = 2000 lb.in to the machine at full load operation. The gears used in the system are spur gears having pressure angle 20, number of teeth of gear D is 40 teeth, and of gear B is 20 teeth. Assuming no power losses, then: (a) Determine the minimum diameter of shaft AC, knowing that shaft AC is to be made of hot rolled steed having yield strength = 48 kpsi, ultimate strength = 75 kpsi, fully corrected endurance limit Se = 26 kpsi, and the estimated fatigue stress concentration factors at shoulders in bending and torsion are respectively K = 2.1 and Ky, = 1.9. Use DE-Soderberg method with fatigue factor of safety n = 1.5. (b) Determine the rotational speed of the driving sprocket Q in units of rpm, knowing that the speed ratio of the sprockets is to be no lng = 2. Note that Qis the smaller sprocket as shown in the figure.. (c) Select an appropriate double strand sprocket-chain drive to be used as shown in this system. You need to identify (1) chain number, (2) number of teeth on driving sprocket, (3) number of teeth on driven sprocket, (4) length of the chain in pitches. Motor 7.5 in D 30 in 4 in 12 in T,"