Mechanical Engineering Answers

7.) Flange bolt couplings consist of 10 steel 25 mm steel bolts spaced evenly around a bolt circle 400 mm in diameter. If the coupling is subjected to a torque of 20 kN-m, determine the maximum stress in the bolts?

8.) The energy required to punch a square from 30mm thick plate is 20KJ. If the ultimate strength of plate is 450Mpa, determine the maximum sides of square that can be punch.

Answer: S=24.69mm

6.) The power required to shear a plate 60mm thick for 20sec is 8KW. If the ultimate strength of plate materials is 4oo Mpa, How wide should the plate be?

Answer: b= 222.22mm

5.) A plate 400mm wide and 0.03 mm thick with strength of 400Mpa is to shear. During shearing process a 1000mm mean diameter flywheel changes its speed from 220 to 200 rpm. Determine the weight of flywheel to be used.

Answer: W=61.34 KN

3.) During a punching process of 350 kg flywheel the speed varies 250 to 220 rpm with 1.2m mean diameter. Determine the kinetic energy needed.

Answer: 9.74 kN-m

1. Determine the accumulated value of P2000.00 in 5 years if it is invested at 11%

compounded quarterly. (Please show solution with correct answer)

3. A machine costs P20,000 today. If inflation rate is 6% per year and interest is 10% per

year, what will be the appropriate future value of the machine, adjusted for inflation, in

five years? (Please show solution with correct answer)

An open flat belt is to transmit 8 kW. The small pulley has a diameter of 175 mm and rotates at 810 r/min, whilst the large pulley runs at approximately 250 r/min. Both pulleys have a width of 110 mm. The centre distance between the pulleys is 800 mm. Assume a factor of safety of eight (8) and an ultimate tensile stress for the flat belt material of 20 MPa. Assume µ = 0.35.

An open flat belt is to transmit 8 kW. The small pulley has a diameter of 175 mm and rotates at

810 r/min, whilst the large pulley runs at approximately 250 r/min. Both pulleys have a width

of 110 mm. The centre distance between the pulleys is 800 mm. Assume a factor of safety of

eight (8) and an ultimate tensile stress for the flat belt material of 20 MPa. Assume µ = 0.35.

2.1 Specify a belt; i.e. the width, thickness, length and grade

2.2 Calculate a suitable initial tension.

a 60 mm diameter pipe contains glycerine at2 20 c flowing at 8.5 m3/h. verify that the flow is laminar. for the pressure measurements hown, is the flow ascending or descending? what is the head loss for these pressure? take p glycerine = 1258 kg/m3, U glycerine = 1.49, g = 9.807