ETD 363 Practice Exam 2 Problems_Spring 2023

A soft start electrical motor that delivers 21,43 KW at 1440 rpm must be connected to a stone crusher (hammer mill type) via a wedge belt drive. The crusher must operate 24 hours per day at a recommended shaft speed of 503,5 rpm,while the centre line distance must not exceed 1000 mm. The crusher shaft is 50 mm in diameter. 1.State the product design specification considering the functionality as a design factor. 2.Use the Fenner catalogue to specify the type and number of wedge belts required for the drive 3.Draw and label all critical parts of the belt drive according to the information provided above

It is required to design a chain drive with a duplex chain to connect a 15kW . 1400r.p.m electric motor to  a transmission shaft running at 350 r.p.m.The operation involves moderate shocks.Assume that centre distance is nearly 40 times the chain pitch initially.What is the no of teeth on driving sprocket? What is the no of teeth in driven sprocket? Select a suitable roller chain.What is it's label? What is the pitch circle diameter of a driving sprocket? What is the pitch circle diameter of driven sprocket? Total no of chain links is Corrected center to center distance is?

how does a belt drive's velocity ratio affect performance when some slip occurs between the belt and the two pulleys?

...An open V-belt drive operates under the following conditions: coefficient of friction between belt and pulley of 0.1, tight side tension of 1500 N, angle of contact of 120°, and groove angle of 40°. Which of the following is the slack side tension of the belt drive? Group of answer choices 3370 N 810 N 670 N 2770 N

design Using safety factor of (3), determine a minimum diameter for the shaft shown in FIGURE 2. The shaft material AISI 1050 HR (hot rolled) steel. The power to be transmitted is (8 KW) at (900 rpm). The diameter of the pulley is (250 mm) and the ratio of belt tensions is (2.5). (90 percent) reliability is desired.   FIGURE 2

If the inertia is 90 lb·ft2 and the speed of the driven shaft is to be increased from 0 to 2,500 rpm in 5 seconds, shaft material is of SAE 4140 with the yield strength of 110,000 lb/in2, find the clutch starting torque in lb·ft. a 191 b 162 c 146 d 128 e 232 Correct Answer is 146

An SAE 1050 Cold drawn steel is to be used for a square or rectangular key.  The shaft is made of SAE 4340 OQT400 and the diameter is 2.5 inches.  The torque transmitted by shaft is 15,000 lb-in. Design factor, N=2. The hub is made of SAE4340 OQT400and the  length of hub  is designed to be 3 inches.  Which one of the following square keys can be used for this design? Note: How do I determine answer if the diameter is between two values?   (a)  0.375 in x 0.375 in    (b)  0.500 in x 0.500 in    (c)  0.625 in x 0.625 in   (d)  0.750 in x 0.750 in

An electric motor running at 1200 rpm drives a punch press shaft at 100 rpm by means of a 130 mm wide and 8 mm thick belt. When the clutch is engaged, the belt slips. To correct this condition, an idler pulley was installed to increase the angle of contact, but the same belt and pulley were used. The original contact angle on the 200 mm motor pulley is 160 degrees. The original tension ratio is 2.4 and the net tension is 12 N/mm of the belt width. If an increase in transmission capacity of 20 % will prevent slippage, determine the new angle of contact. Please show your correct and complete solution to this problem. ASAP! Thanks.

A chain sprocket system is designed to drive a shaft. Assume the following conditions: Use SAE1018 steel for the key (which is the weakest material in comparison to other components) The chain sprocket has a bore diameter of 2.5" and the hub length of 3.125". The sprocket delivers 110 horsepower to a shaft with the rotation of 1700 rpm. Safety factor of 3 Determine 1). The dimensions of the square key: Width: in Minimum length (so the key will not fail): in 2). The minimum contact length on the hub (so the hub will not fail): in

You are to select a suitable drive for power transmission for an industrial equipment. As a design engineer, you select a belt-drive system over gear drive or a chain and sprocket drive. Justify your selection of a belt drive. (Parameters: Cost, Speed, Maintenance, Flexibility, Distance between driving and driven shaft, Noise and Vibration).

The stresses in a powered screw include: ___________________________. True or False with explanation For both shaft design and spring design, the running frequency should be at least two times lower than the first mode of natural frequency. True_ False__. The major stress in a spring comes from the direct shear. True_ False__. The natural frequency of a spring can be reduced by reducing the weight of the wire. True_ False__. Considering the contact fatigue of a gear, the wear factor should be higher than the gear factor. True_ False__. The pitch of the body coil can be calculated from the number of active coils and the critical length of the spring. True_ False__

Define the following terms as applied to rolling contact bearings:(a) Basic static load rating (b) Static equivalent load(c) Basic dynamic load rating (d) Dynamic equivalent load

The shaft of a belt drive is made of AISI C1020 as rolled steel. The belt tensions vary continuously during transmission at a constant tension ratio of 3:1; the maximum tight side tension being 400 lb and the minimum tight side tension is expected to be 160 lb, at a pulley diameter of 12 inches. For a Goodman factor of safety of 1.8, recommend the diameter of the shaft. Consider a machined surface and the effect of a hardened profile keyway in the shaft.

Fill the blank: 1) In fatigue failure analysis, regarding S-N diagram, S stands for........ and N stands for ............   2) The circle on which the involute profile of the gear teeth are generated is called .......... circle   3) The helix angle on the worm is ......... than the one on the mating gear.

Describe the Torsional moment or torque, T?

What are the mechanics of torque tube failure and the failure pattern?

Define the term load-displacement relations?

Case 1: case of the twisted shaft)The shafting shown in Figure 2.51 was taken from a mill transfer chain that was frequently overloaded, causing the shaft (made of low-carbon steel) to fail by torsion shear. It has obviously been loaded in torsion beyond its elastic limit into the plastic range and has taken a permanent set. Since the sprocket and bearing bores are bot easily changed to substitute a larger diameter shaft, what type of replacement shaft will solve the problem? What different mechanical properties must it posses so it will not again fail by torsion shear?

The external and internal diameter of a single plate clutch are 125 mm and 100 mm, respectively. It is used to transmit power at limited (maximum) axial pressure of 0.2 MPa. Which of the following is the axial force exerted by the springs? Assume uniform wear conditions. Choices:  790N1960N 440N 980N

a single-start, square-threaded power screw with the following parameters: PARTS A - D circle final answers for each part A -  A weight of 1500 N must be lifted. What is the total required torque necessary to lift this weight? Give your answer in units of N m. Part B - if the available power to drive the screw is 1,011 Watts, determine the fastest speed at which the weight can rise. Give your answer in units of mm/s, Part C - The efficiency of the preceding power screw (expressed as a number between 0 and 1, not as a percentage) is ? Part D - Suppose a high-quality thrust bearing was used to eliminate the collar friction. The efficiency of the screw would now be?

Read the question carefully and give me right solution according to the question.  Note : No need the diagram. Complete information given. A flat belt drive connects two pulleys 5 meters apart. The 2m pulley diameter driver rotates at 350rpm, and the driven pulley has a diameter of 1.5m. The thickness and the mass of the belt drive is 5mm and 0.6kg respectively. The coefficient of friction between the belt and the pulley is 0.25. The belt experience 3% of slip during power transmission with a maximum tension of 1200N. Calculate the speed and torque of the driven shaft?

Question 04: Discuss the comparative study between chain and belt drives. How are they useful in the field of mechanical engineering, give some practical examples?

The factor of safety against slipping in the friction clutch = 1.3; coefficient of friction=0.3; working speed= 600 rpm; friction surface number= 2; If required clamping force = 2917 N, clutch outer diameter = 400 mm, clutch inner diameter = 160 mm, what is the transmitted power?

A double square thread power screw is to raise a load of 70 kN. The screw has a mean diameter of 33.375 mm and a pitch of 6 mm. The coefficient of thread friction and collar friction are 0.13 and 0.10, respectively. The collar mean diameter is 90 mm and the screw turns at 90 rpm. Which of the following is the torque required to raise the load without friction effect? Group of answer choices 66845 N-mm 133690 N-mm 236078 N-mm 334840 N-mm

A 02-series single-row deep-groove ball bearing is to be selected from Table 11–2 for the application conditions specified in the table. Assume Table 11–1 is applicable if needed. The value of radial load Fr = 8 kN, axial load Fa = 2 kN, design life LD = 2.40(108), ring rotation factor V = 1, and reliability RD = 0.98. Assuming that the values taken from Table 11–1 are X = 0.56 and Y = 1.63, determine the equivalent radial load rating for this application.  What is the equivalent radial load rating for this application in kN?

Express the compatibility conditions in terms of the displacements caused by the loading?