II. Preventive Maintenance

1. What is preventive maintenance?=

2. Give at least 5 defects on each category.

Metal Parts                           Rubber, Fiber, Plastic, Glass fiber

1.                               1.

2.                               2.

3.                               3.

4.                               4.

5.                               5.

Control sys. Components                   Electrical components and actuators

1.                               1.  

2.                               2.

3.                               3.

4.                               4.

5.                               5.

Liquid system

1.

2.

3.

4.

5.

Thermodynamics

If you use a number from a table can you please show me a picture from what table you use because that's what I'm mainly confused about

1. (ans:159.50)

Saturated water vapor at 14.85 bar enters an insulated throttling valve which drops the pressure to 1.50 bar. Determine the temperature (^oC) of the steam at the exit of the valve.

Note: Give your answer to two decimal places.

Shallow drawing is defined as a cup drawing where the cup height is less than or equal to ________________ the diameter of the cup.

1 points   

QUESTION 17

Clamping can be kept on the outside diameter in the case of a boring fixture even when the wall thickness is small.

True

False

1 points   

QUESTION 18

A fixture should be designed such that the cutting tool forces act against the clamping arrangement.   

True

False

QUESTION 13

Bend allowance is provided in a bending operation to account for increased length due to applied stresses.

True

False

1 points   

QUESTION 14

A cylindrical object when located by a V-block arrests 4 degrees of freedom.

True

False

1 points   

QUESTION 15

An indirect pilot is attached directly to ______________ in the case of a sheet metal shearing die.

Principle of momentum and linear momentum: A penguin inside a box (10 Newtons) ascends the inclined plane (π / 3 Radians) completely smooth due to an impulsive force that gives it an initial speed of 36 km / h. Calculate the seconds it would take to come to a complete stop (rest). It is not necessary to know the magnitude of Impulsive Force F as you can see in your equation of the principle of impulse and linear momentum (It stopped acting at the moment it reaches the indicated speed)

QUESTION 10

In metal cutting, the application of cutting fluid decreases the coefficient of friction thereby improving the machining efficiency.

True

False

1 points   

QUESTION 11

Increasing the rake angle of the cutting tool significantly reduces the power consumption in turning.

True

False

1 points   

QUESTION 12

A work holder must position or locate a workpiece in a definite relation to the cutting tool and must withstand ________________________ forces.

Plot the shear strain and the shear strain rate as functions of the shear angle, for several tool rake angles. Describe your observations.

Search for the thought experiment called “Maxwell’s demon” and summarize its importance regarding the second law of thermodynamics in your own words in a half a page long essay. Add the references at the end of the essay.

In C

Exercise 8.1 A word is said to be “abecedarian” if the letters in the word appear in alphabetical order. For example, the following are all 6-letter English abecedarian words.

abdest, acknow, acorsy, adempt, adipsy, agnosy, be?st, behint, beknow, bijoux, biopsy, cestuy, chintz, de?ux, dehors, dehort, deinos, diluvy, dimpsy

a. Describe an algorithm for checking whether a given word (String) is abecedarian, assuming that the word contains only lower-case letters. Your algorithm can be iterative or recursive.

b. Implement your algorithm in a function called IsAbecedarian().

Essay about fire sprinkler in your own words.

A car’s radiator is a heat exchanger with 2 kg/s of hot water entering at 100 C and leaving at 60 C with a pressure of 200 kPa. Air flows across the heat exchanger entering at 25 C and leaving at 40 C. What is the volume flowrate of air needed in m³/s? (18.9 m3/s)

0.5 kg of R12 are contained in a piston/cylinder and has a quality of 75% and a temperature of 0 C. Heat is transferred at constant pressure until the R12 is a saturated vapor. Determine: a) the initial volume of the R12; b) the work done; c) the heat transfer; d) the T-v diagram.

Ans:

a) 0.0208 m3 b) 2.13 kJ c) 18.9 kJ

PLEASE ANSWER ALL

1. Calculate the molar enthalpy of combustion at 25?C and 1 bar pressure of a gas of volumetric analysis 12% H2, 29% CO, 2.6% CH4, 0.4% C2H4, 4% CO2, and 52% N2 for the H2O in the vapour phase and in the liquid phase.

ANSWER (- 137 240 kJ/kmol; - 145 158 kJ/kmol)

2. A gaseous fuel has the following volumetric composition: CH4 0.38, H2 0.26, N2 0.06, CO 0.26, CO2 0.04. Find the stoichiometric air/fuel ratio by volume and the corresponding wet and dry volumetric analyses of the products of combustion.

ANSWER (4.86; CO2 0.121, H2O 0.182, N2 0.697; CO2 0.1485, N2 0.8515)

ANSWER ALL

1. A quantity of coal used in a boiler had the following analysis: 82% C; 5% H; 6% 0; 2% N; 5% ash. The dry flue gas analysis showed 14% CO2 and some oxygen. Calculate: (i) The oxygen content of the dry flue gas; (ii) The A/F ratio and the excess air supplied.

ANSWER (5.52%; 14.29/1; 31.8%)

2. The enthalpy of combustion of propane gas, C3H8, at 25 ?C with the H2O in the products in the liquid phase is – 50 360 kJ/kg. Calculate the enthalpy of combustion with the H2O in the vapour phase per unit mass of fuel and per unit amount of substance of fuel. ANSWER (- 46 364 kJ/kg; - 2 040 030 kJ/kmol)