Mechanical Engineering Answers

Cylinder subjected to internal pressure with an internal diameter of 350 mm and a 25 mm wall thickness. For the cylinder material, KIC = 80 MPa√m, Sy = 1172 MPa, and Sut = 1324 MPa. If the cylinder contains a radial crack in the longitudinal direction of depth 12.5, mm determine the pressure that will cause uncontrollable crack growth.

 Explain the constructional details and working of the following boilers in details. ➢ Cochran Boiler ➢ La-Mont Boiler ➢ Velox Boiler Also write their significance and applications in various industries

What do you mean by Mountings and Accessories of Boiler? Which according to you is an integral part of the boiler? Explain any three mountings and accessories in details with their specifications and usage.

What do you mean by Steam Turbines? Explain the difference between Impulse and Reaction turbines. What is their significance. Which according to you is better of the two and why

: What do you mean by Steam generators or Boilers? How do we classify them? Also write its applications in various industries.

An Aluminium Alloy roller with diameter 25mm and length 50mm rolls on the inside of a cast iron ring

having an inside radius of 100mm, which is 50mm thick. Find the maximum force ‘F’ that can be used if

the maximum pressure is not exceeding 100 Mpa.

A fit or assembly of pin and hole is designated by 55mm H9/d9/

a) Describe what kind of fit it is.

b) Find: i)tolerances for pin & hole ii) Deviations (Upper, Lower and Fundamental) for both hole and pin

iii) The maximum, minimum, mean and most frequent clearances.(hint: mean is the most frequent value

in normal distribution)

c) Neatly sketch the fit/assembly in a graph paper and show all the pertinent dimensions

d) Assume the natural spread and tolerance coincide for both shaft and hole. What % of fit was less than

the minimum clearance?

(find σ for shaft, hole and clearance. For the σ of clearance, use the population combination formula

mentioned in the study material named statistical considerations)

a shaft manufacturer has produced 500 ms pipes of nominal outside diameter of 150mm. measurement show the maximum diameter to be 151.1mm while minimum diameter to be 149.3mm. hoever during shipment pipes of diameter 150+-0.5mm were accepted and the rest were rejected.assume gaussian/normal distribution.

a hollow cylindrical column is to carry a load of 20 kn where the outside diameter of the column is 100 mm. the length of the column is 5m. if the length of the column is mild steel (sy=250 mpa,e=200 gpa) determine the minimum thickness required for the column. use factor of safety of 2. considered eccentricity e=0.2m

A fluid is heated reversibly at a constant pressure of 1.05 bar until it has a specific

volume of 0.1 m3

/kg. It is then compressed reversibly according to a law pv=constant to a

pressure of 4.2 bar, then allowed to expand reversibly according to the law

pv1.3=constant, and is finally heated at constant volume back to the initial conditions. The

work done in the constant pressure process is 515 Nm and the mass of the fluid present is

0.2 kg. Calculate the net work done on or by the fluid in the cycle and sketch the cycle on

a p-v diagram