(Chapter 10)
Q: Explain the difference between coarse and fine pearlite?
In: Mechanical Engineering
only for field engineers please: why would you choose to this segment "measurement while drilling"?
why would you choose " well completion"?
In: Mechanical Engineering
(Materials Testing Results)
Q: The 30% rubber group reported Rockwell numbers for fresh 48 hour and old as 12.5,21.5, and 88.5. How do you explain these results?
In: Mechanical Engineering
(Materials Testing Results)
Q: The 30% rubber group reported a strain at yield of 0.38 and a strain at break of 0.3. Please explain this change.
In: Mechanical Engineering
In: Mechanical Engineering
A helical compression spring has 14 active coils and the free length is 12.5in. The outside diameter is 7/16 in and the spring has squared and ground ends. The end plates are constrained to be parallel. The material is music wire with presetting. The wire diameter is 0.042 in. Determine: (1) for static conditions compute the spring index, the solid length, the stress when the spring is compressed to the solid length. Check if static yielding occurs while the spring is brought to its solid length; (2) for dynamic conditions with Pmin=0.9 lb and Pmax=2.9 lb, check if the spring experiences torsional endurance limit fatigue torsional yielding, or torsional fatigue failure. Assume a survival probability of 90%, unpeened coil, and fatigue failure based on 50x103 cycles
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Using Excel, plot the internal temperature of a computer chip k=1.38 W/(m-K) that generated 2,000 W of power. The chip is 10 cm wide. Assume one side is at 40oC and the other is at 45oC
In: Mechanical Engineering
The mean diameter of the square threaded screw having pitch of
10 mm is 50 mm. A load of 20 kN is lifted through a distance of 170
mm. Find the work done in lifting the load and the efficiency of
the screw, when
1. The load rotates with the screw, and
2. The load rests on the loose head which does not rotate with the
screw.
The external and internal diameter of the bearing surface of the
loose head are 60 mm and 10 mm respectively. The coefficient of
friction for the screw and the bearing surface may be taken as
0.08.
In: Mechanical Engineering
Find an important engineering failure that involves some of the topics discussed in MSE 350. Describe the failure, why it occurred, the damage (human, environmental, and economic) and the changes that could have been made in the design to avoid the failure. Was the failure caused by lack of engineering knowledge at the time, engineering error, or management/government error? Discuss!!
For each of the following common items, identify what they are commonly made of, the material type (composite, metal, semiconductor, polymer , ceramic, glass. Describe why that material type is used. Include at least two references for your answers (websites are fine, but try and find good ones). If more than one material type is used in the items, include them all! Be careful to use proper engineering vocabulary when answering this question!
Abrasives for grinding metal
Automobiles Integrated circuits
Airplanes Bridges
Solar panels
Latex paint
Soda bottles
Polyvinylchloride (PVC) plumbing pipe
In: Mechanical Engineering
A centrifugal compressor has 22 radial impellers with an
impeller exit radius of r2 = 0.25m.
Assuming the mass flow rate through the compressor is mdot =
10kg/s, the shaft speed is
omega = 10,000 rpm, and the inlet flow is swirl free,
calculate
a) the total shaft power Ps in kW
b) the total temperature rise (?Tt)in the compressor (assume ? =
1.4 and cp = 1004 J/(kg K))
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The electrical conductivity and the electron mobility for copper at room temperature are 6.0 X 107 (W.m)-1 and 0.003 m2/V-s, respectively. Compute the number of free electrons per copper atom.
In: Mechanical Engineering
QUESTION 1
Tick the option which correctly describes the units of
parameters defined in an operation sheet?
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a. |
Cutting Speed (ft/min), Spindle Speed (rev/min), Feed (in/rev), Depth of Cut(in) |
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b. |
Cutting Speed (in/min), Spindle Speed (rev/sec), Feed (mm/rev), Depth of Cut(in) |
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c. |
Cutting Speed (ft/min), Spindle Speed (rev/min), Feed (in/rev), Depth of Cut(mm) |
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d. |
Cutting Speed (ft/sec), Spindle Speed (rev/min), Feed (mm/rev), Depth of Cut(mm) |
10 points
QUESTION 2
What steps are necessary for Process Planning of a job shop?
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a. |
Size of Components, Shape of components, Tolerances |
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b. |
Material |
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c. |
No. of pieces to be produced, Available machine tools, Material properties |
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d. |
All of the above |
10 points
QUESTION 3
Which one of the characteristics does not define the work of a route sheet?
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a. |
Lists all manufacturing operations & associated machine tools |
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b. |
Describes every machining & assembly operation |
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c. |
Specifies process sequence of a job |
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d. |
Defines path of material |
10 points
QUESTION 4
Which of the statements holds true for a job shop?
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a. |
Variety of products can be manufactured |
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b. |
Workers need not require to not have high skill levels |
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c. |
Large manufacturing lot sizes are avoided |
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d. |
All of the above |
10 points
QUESTION 5
Which is one of the difficulty that Digital Simulation faces in absence of manufacturing system design?
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a. |
Data is easy to secure, accurate & non-conflicting |
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b. |
All system analyses are subject to errors of omission & commission |
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c. |
Environment cannot change the system and vice versa |
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d. |
Manufacturing system are simple, easy to define and has clear goals |
10 points
QUESTION 6
Which of these is a disadvantage of application of PLC in a flow shop?
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a. |
Reprogrammable |
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b. |
Machines are flexible |
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c. |
Increased Construction time |
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d. |
Relay panels are no more vulnerable to electronic noise |
10 points
QUESTION 7
In a manufacturing system, the critical control functions are
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a. |
Inventory control, Production rate & mix control |
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b. |
Quality control & Machine tool control |
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c. |
Inventory Control, Machine tool control & Quality Control |
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d. |
Both a & b |
In: Mechanical Engineering
If a strain gage is placed in the wing of an aircraft where the temperature drops by 50 degrees F in flight. How do you configure the bridge to compensate for the resulting error?
In: Mechanical Engineering
Water vapor at 5 bar, 320°C enters a turbine operating at steady
state with a volumetric flow rate of 3 m3/s and expands
adiabatically to an exit state of 1 bar, 160°C. Kinetic and
potential energy effects are negligible.
Determine for the turbine:
(a) the power developed, in kW.
(b) the rate of entropy production, in kW/K.
(c) the percent isentropic turbine efficiency.
In: Mechanical Engineering
Regarding Fused Deposition Modeling (FDM) process, answer the following questions with a detailed explanation:
1. How and why temperature, pressure/force, and time impact the following quality issues:
- Surface finish
- Dimensional accuracy
2. ?Identify and explain the reason behind the key processing limits relevant to the FDM process that are based on:
- Limits of the material being processed
- Limits of the equipment being processed
In: Mechanical Engineering