DieselShip's Online Content Library

Q7. What are the major types of stainless steels used on merchant ships? Briefly explain each type. Which grades would you recommended for use in sea water environment? Why?

Q3. Why Engineering Materials are tested prior manufacturing of their components.

i) Describe the various destructive and non-destructive tests carried out on materials for shipboard used. (6)

ii) Explain the purpose of each test and where the same applied. (10)

Q6. Explain the following terms and give examples of where each condition might occur

a) Stress Corrosion cracking (6)

b) Creep cracking (5)

c) Corrosion fatigue (5)

Q1. Write short notes on the following pertaining to the use of copper alloys in seawater systems.

a. Use of copper nickel and formation of protective film for use in seawater. (4)

b. Cavitation. (4)

c. Dezincification. (4)

d. Marine biofouling. (4)

Q7. (a) Describe each of following: (8)

(i) Work hardening

(ii) Nitriding

(iii) Cold working

(iv) Normalising

(b) With reference to the component parts of shipboard machinery and equipment, state with reason, One example of where EACH of (a), (i) (ii), (iii) and (iv) may be used. (8)

Q1. i) Draw the stress Vs strain curve showing the different phases of change that occurs when an elastic material is subjected to load. (5)

ii) What is plastic deformation of material and how it is caused? Explain yield stress & how strain hardening is caused? Where is this phenomenon successfully used? (6)

iii) Explain fatigue and how fatigue failure occurs? suggest means in practice as to how fatigue failure can we avoided. (5)

Q2. (i) Discuss the use of non-metals onboard ships & name some of the common nonmetals used (4)

(ii) What are their areas of application on ships? (4)

(iii) Name the advantages & also the limitations in using non-ferrous materials (8)

Q7. (a) Why is heat treatment necessary for carbon steel? (6)

(b) Describe the various heat treatment processes and their benefits. (10)

Q5. (a) How is the tensile strength of a metal determined? What other information is obtained when a tensile test is made? (8)

(b) Name the non-destructive tests used during the manufacture and service of a diesel engine components and associated equipments. Give an example of where each test is used. (8)

Q1. Describe materials used for following equipment’s with composition and qualities required.

a) Propeller. (4)

b) Propeller Shaft. (4)

c) Engine Gears. (4)

d) Bearings. (4)

Q7. Write short notes on the following:

(a) Ultrasonic testing (8)

(b) Shaft earthing device (8)

Q2. (a) Describe in detail how brittle fracture is instrumental in causing failure of materials. (6) (b) Describe how a material is tested to assess the resistance to this type of failure. (4)

(c) Suggest where this type of failure would be likely and explain how the likelihood of failure is reduced. (6)