.IICHAHICAL IIHIIINIIIIAINII


Time Allowed: 3 Hours Maximum Marks: 300 CamlitlJItes s1wulll aitemptquestions 1 and 5 whkh are compdsory and"III' Ihree o/Ihe remaining queslions sekclion aJ kast one question sekcting aJ kastone quesllonjromeach Seclion.
SEc:nONA
Attempt any three of the following
Define the following terms commonly used in laying out the cam profiles:
(i)Base circle
(ii)Trace point
Pitch curve
(iv)Pressure angle
The following notations refer to a Tangent cam with straight flank, Circular nose and roller
follower:
Rc= Base circle radius
Rr Roller radius
Rn Nose radius
alpha= Semi-angle of action of the cam
beta Angle by which cam rotates for contact for roller with the flank
theta= Any angle by which the cam has rotated
h Lift or the stroke at an angle theta
Draw a neat sketch of this cam. Determine the expressions for evaluating the lift velocity
(v)and the acceleration of the follower when the cam has turned through an angle theta (which is less than beta)

hollow shaft 30 mm inner diameter and 50 mm outer diameter is subjected to a twisting moment of 800 N-m and an axial compressive force of 40 kN. Determine the factor of safety according to theory of failure based on Normal stress theory, Maximum shear stress theory and Distortion energy theory. The tensile and compressive yield strength of material is 280 N/mm2 and Poisson's ratio 0.3.

(c)Construct the bending moment and shearing force diagram for the beam as shown in the figure liven below. <img src='./qimages/1134-1c.jpg'>

(d)What are the various types of plain carbon steel? List important mechanical properties and their common industrial applications.
A 350 N electronic instrument is attached to a ship deck which Vibrates at an amplitude of 1.60 mm at 50 Hz. The instruments to be isolated from the deck with four flexible mounts Determine the required combined spring constant of the mounts such that the amplitude of vibration of the instrument is no more than 0.130 mm. If the springs are equal, what is the spring constant of each mount? WhatlS the static deflection of each mount?
compressor requires 120 kW to run at 240 rpm from an electric motor of speed 750 rpm, by means of a V-belt drive. The diameter of the compressor shaft pulley should not be more than 1000 mm while the centre distance between the shafts is 2000 mm. The belt speed should not exceed 25 m/sec. Determine the number of V -belts required to transmit the power, if each belt has a cross sectional area of 375 mm2, denSity 1000 kg/m3 and an allowable tensile stress of 25 MPa The pulley groove angle lS 40° and coefficient of friction between the belt and pulley Sides lS 0.25.

3.(a)A circular disc 50 cm outSide diameter has a central hole and rotates at a uniform speed about an axis through its centre. The diameter of the hole is such that the maximum stress due to rotation is 85% of that in thin ring whose mean diameter is also 50 cm. If both are of the same material and rotate at the same speed, determine the diameter of the central hole and speed of the disc for the data given below Allowable stress 900 kg/cm2
Specific wetght=78gm/cm2
POisson's ratio 0.3

A cantilever of length L is loaded by a uniformly increasing load, starting from zero at the free end to a max1mum of w0 at the fixed end. The free end is propped to the level of fixed end. Determine the reaction at the prop and equation to the elastic curve along with the slope at the propped end. E1 is assumed constant
What are the important properties possessed by stainless steel?
(ii)Give composition and uses of following stainless steels:
(1)Ferritic stainless steel

(2)Martensitic stainless steel

(3)Austenitic stainless steel



(b)What are the composite materials? Explain major composite materials, depending upon state of reinforcing phase.

SECTION B
Answer any three of the folloWlng
(a)During orthogonal machining with an HSS Tool, the rake angle was 50, the unreformed chip thickness was 0.25 mm and Width of cut was 4°nm. Assuming shear strength of work material to be 350 N/mm2 and coefficient of friction to be 0.5, estimate cutting force and thrust force.

List various types of chips that are fanned in cutting and the conditions in which they occur.

(c)Following is information regarding a manufacturing enterprise:
Total fixed costs Rs.4,500
Total variable costs Rs7,500
Total sales Rs.15,000
Units sold= 5,000
Find out
Break-even point in units
Margin of safety
Profit
(iv)Volume of sales to earn a profit of Rs 6,000


A work measurement study was conducted in a manufacturing company for 8 hours and following observations were made Idle time: 15% Performance rating: 120% Allowance time: 12% of standard time Number of units produced:320 Calculate the standard time for the task


6.(a)In drilling of 20 mm diameter hole in a mild steel solid block of 25 rum thickness, the feed used is 0.25 mm/rev. The drill must be changed after making 10 holes if it is rotated at 250 rpm But drill can produce 50 holes if rotated at 200 rpm How many holes can be produced if rpm is 150?
Prove that in EDM, using resistance-capacitance relaxation c1rcuit with a constant DC source, for maximum power delivery, the discharge voltage should be 72% of supply voltage. How is the MRR affected by variation in resistance, mean current, capacitance and spark gap?
Five different machines can do any of the five required jobs, with different profits resulting from each assignment as shown in the table. Find out maximum profit possible through optimal asSignments <img src='./qimages/1134-7a.jpg'>

A project is composed of eleven activities The time estimates are given below: <img src='./qimages/1134-7b.jpg'>
(1)Draw the network diagram of project.
(ii)Calculate slack time for each node.
Determine critical path

What is friction hill in rolling process? State the condition of skidding in rolling How does the roll pressure change with front tensiOn and back tensiOn, and the roll diameter?
company makes 16 gm toffees (net weight) for sale. As policy, a toffee is considered unacceptable if the net weight is more than 0.1 gm greater or less than this amount. The company took 20 samples of five toffees each (100 in total) from production line when the process was known to be in control. The average Weight for 100 toffees was 16.003 gm and the average range for the 20 samples was 0.093 gm
(i)Compute the upper and lower limits for three Sigma X bar -chart.
(ii)Compute the upper and lower limits for three Sigma R-chart.
(iii)Based on and suppose the company now samples 5 toffees from the production line.

The net weight of thee toffees are 16.018, 15.870, 16.115, 16.002 and 16.005 gm Determine whether or not the process is in control. If not, specify what the problem is and how you determined this. [Given that for sample Size of 5 d2=233 For R chart UCLR= d4 R bar and LCLR=d3 R bar where d4=2.11 and
Write a "c" pro gram to calculate the factorial of a positive integer quantity by incorporating user defined function for calculating factorial in main program.