Question

A 60-mm diameter solid 1030 cold-drawn and machined steel shaft is mounted on anti-friction roller bearings modeled as simple supports and carries two pulleys with belts wrapped B = 150° at a constant, non-critical speed. The shaft has the yield, ultimate and endurance limit strengths of 1030 cold-drawn steel. It is required that the shaft has infinite fatigue life. It is also required that deflection not exceed 1.5 mm at any point and that the maximum angle of twist not exceed 0.5º Answer the following question in the essay section of this exam being sure to complete your calculations for deflection, twist, fatigue and coefficient of friction on your scratch sheet. 500 mm dia 250 mm 750 mm 250 mm B A Bearing D Bearing B с 1350 N 450 N 450 N 1350 N Note, choose one or more than one of the following MC answers and then type the letter (s) corresponding to the question number in the essay section of this problem with supporting calculations contained on the scratch sheet. If the answer requires "the correct answer is__"type that in the essay section as well. 2a) What are the deflection, twist and FS for fatigue? a) Ymax=-0.2 mm, max =-1.30, FS=4 b) Ymax=-0.5 mm, max =0.3., FS<1 c) ymax=-0.63 mm, max =0.09, FS>8 d) Ymax=-1.3 mm, max =0.2°, FS>4 e) All of the above f) None of the above, the correct answer is: 2b) Does shaft meet fatigue, deflection, and twist requirements?: a) Deflection is too great, twist is OK, fatigue life is infinite b) Deflection is too little, twist is too great, fatigue life is finite c) Deflection is just right, twist is too little, fatigue life is infinite d) Deflection is OK, twist is OK, fatigue life is infinite e) All of the above f) None of the above, the correct answer is: 2c) What is coefficient of friction, f? Note Fmax/Fmin=exp(f*8)? [Note: 8 should be in radians) a) f=0.3 b) f=4.5 c)f=1.5 d) f=0.42 e) All of the above f) None of the above, the correct answer is:

Answer 1

SOLUTION:-

S.NO.	ANS
2a	B
2b	D
2c	D