DieselShip's Online Content Library

Q1. Write a report to the Superintendent Engineer regarding a number of cases of severe damage to medium speed engine exhaust valves in the previous 12 months. The report must outline the probable cause of the damage and must suggest future steps to avoid similar incidents. (16)

Q2. With reference to turbocharger systems;

a. Describe, with the aid of a sketch, a turbocharger jet assist system, explaining how it and why it is used. (10)

b. Describe with the aid of a sketch a waste gate and by pass system explaining why such an arrangement is fitted. (6)

Q5. With reference to marine diesel engine selective catalytic reduction (SCR)

(a) Explain, with the aid of a graph, the influence that fuel sulphur content has on the operation of an SCR unit (4)

(b) Explain how the operation of a turbocharger system can have a detrimental effect on the unity when burning fuels with higher sulphur content (4)

(c) Describe, with the aid of a sketch, a system which maintains good engine performance of the turbocharger system and good NOx reduction when burning fuels with higher sulphur content, explaining how conflicting conditions are met (8)

Q5. (a) Sketch a diesel engine high pressure common rail fuel system, labelling the MAIN parts. (8)

(b) Describe how the common rail system sketched in part (a) operates, explaining how fuel injection timing is controlled.

Q5. (a) Describe the procedure for entry into, and inspection of, the inside of a starting air receiver, stating the types of defects which may be present with their possible causes. (12)

(b) Describe the procedure of closing up the air receiver and the initial pressurisation to working pressure. (4)

Q8.  With reference to fatigue of engineering components;

(a) Draw an S/N curve for steel, showing the fatigue limit and two representative stress cycle condition on the graph (4)

(b) Explain how a component is designed to avoid fatigue failure, suing the S/N curve drawn in part (a) (4)

(c) Explain how poor maintenance and incorrect machinery operation can result in fatigue failure even though a component is designed to operate below the fatigue limit (8)

Q2. A. Describe, with the aid of a sketch, the lubrication systems of a crosshead type diesel engine. (8)

B. Explain the properties required by the lubricating oil in each of the systems described in part (a), stating how these properties compare with those of a lubricating oil used in the crankcase of a trunk piston type diesel engine

Q7. (a)  Describe, with the aid of a sketch, a main engine fresh water cooling water system, incorporating HT and LT systems.

(b). Describe the charge air supply system for a turbocharged engine, explaining the purpose of each main part. (6)

Q5. Write a procedure for the actions to be taken in the event of an engine Oil mist alarm being activated, stating the reason for EACH action. The procedure must cover the period from activation of the alarm to return of the engine to normal operation. (16)