# Machine Design 6th Sem Mechanical/5522/Feb 2021 Diploma Paper

## Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â SECTION-A

#### Q2. Attempt any THREE questions.Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  3×5=15

i. What are the general considerations in designing a mechanical component?
ii. Write about rankineâ€™s theory of failure for mechanical component.
iii. Illustrate how the stress concentration in a component can be reduced.
iv. What is equivalent twisting moment and equivalent bending moment?
v. Discuss different types of keys.
vi. Explain the necessity of coupling and list various types of couplings.
vii. Discuss different types of rivet joint failures.
viii. Write the points of difference of knuckle joint and cotter joint

## Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  SECTION-B

#### Q3. Attempt any ONE question.Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  Â  1×10=10

Q2. A 45 mm diameter shaft is made of steel with yield strength of 400 MPa.A parallel key of size 14 mm
wide and 9 mm thick made of steel with yield strength of 340 MPais to be used. Find the required length
of key, if the shaft is loaded to transmit the maximum permissible torque. Use maximum shear stress
theory and assume a factor of safety of 2.

Q3. Find the diameter of a solid steel shaft to transmit 20 kW at 200 r.p.m. The ultimate shear stress for the
steel may be taken as 360 MPa and a factor of safety as 8.If a hollow shaft is to be used in place of the
solid shaft, find the inside and outside diameter when the ratio of inside to outside diameters is 0.5.

Q4. Determine the length of the weld run for a plate of size 120 mm wide and 15 mm thick to be welded to
another plate by means of1. A single transverse weld; and2. Double parallel fillet welds when the joint is
subjected tostatic loading if maximum tensile and shear stresses are 70MPa and 56 MPa resp.

Q5. A steam engine cylinder has an effective diameter of 350 mm and the maximum steam pressure acting
on the cylinder cover is 1.25 N/mm2. Calculate the number and size of studs required to fix the cylinder
cover, assuming the permissible stress in the studs as 33 MPa.

## Machine Design 6th Sem Mechanical/5522/Feb 2021 Diploma Paper

### Section A

General considerations in designing a mechanical component

Rankineâ€™s theory of failure for mechanical component.

How the stress concentration in a component can be reduced.

Equivalent twisting moment and equivalent bending moment.

Different types of keys.

Necessity of coupling and list various types of couplings.

Different types of rivet joint failures.

Difference of knuckle joint and cotter joint.

Water CycleÂ

## Machine Design 6th Sem Mechanical/5522/Feb 2021 DiplomaÂ  Â Paper

### Section B

45 mm diameter shaft is made of steel with yield strength of 400 MPa.A parallel key of size 14 mm
wide and 9 mm thick made of steel with yield strength of 340 MPais to be used. Find the required length
of key, if the shaft is loaded to transmit the maximum permissible torque. Use maximum shear stress
theory and assume a factor of safety of 2.

Diameter of a solid steel shaft to transmit 20 kW at 200 r.p.m. The ultimate shear stress for the
steel may be taken as 360 MPa and a factor of safety as 8.If a hollow shaft is to be used in place of the
solid shaft, find the inside and outside diameter when the ratio of inside to outside diameters is 0.5.

Length of the weld run for a plate of size 120 mm wide and 15 mm thick to be welded to
another plate by means of1. A single transverse weld; and2. Double parallel fillet welds when the joint is
subjected tostatic loading if maximum tensile and shear stresses are 70MPa and 56 MPa resp.

Steam engine cylinder has an effective diameter of 350 mm and the maximum steam pressure acting
on the cylinder cover is 1.25 N/mm2. Calculate the number and size of studs required to fix the cylinder
cover, assuming the permissible stress in the studs as 33 MPa.

Effects of land use on environmental qualityÂ

short note on environmental considerations in housing and cityÂ

1.Requirements of a good trap

2.Explain different traps in use.