DieselShip's Online Content Library

Q1. (a) Explain the factors you would consider in deciding whether to open up a cylinder unit for overhaul? After opening the unit and preparing for assembly, how would you decide whether to renew or re-use piston rings?

(b) List the causes of piston ring failure which may result in gas leakage or ring breakage.

Q5. Slow steaming has become the standard operation mode for many ship operators. Discuss various technical issues connected ‘slow steaming’, with particular reference to: (16)

a) Crosshead bearing damage in T/C cutout mode.

b) Cylinder liner cold corrosion

c) Exhaust valve damages

Q5. Misalignment of the main shafting between engine and propeller causes bearing overloads and shaft stress.

A. State the difficulties associated with checking shaft alignment and the reasons why results are unreliable due to external factors. (5)

B. Explain with a simple sketch how a bearing load is assessed. (5)

C. Explain how uneven loading could be rectified. (6)

Q4. a) What is the purpose and key procedures involved in the running-in process of a engine, and how does this process contribute to the long-term reliability and performance of the engine? (8)

b) What are the common issues that can arise during the running-in period of a engine, and what measures should be taken to monitor and address these issues to prevent potential damage or inefficiencies? (8)

Q5. With reference to piston rings. (16)

A. State the reasons for breakage.

B. How maintenance and engine operation could minimize breakage?

C. Explain the possible consequences with respect to performance and safety of operating the engine with broken or severely worn piston rings

PREVIOUSLY ASKED

Q4. With reference to Main engine piston rings:

(a) Analyze the causes of piston ring breakage.

(b) How maintenance and engine operation can minimize piston ring breakage.

(c) Explain the possible consequences with respect to performance and safety of operating the engine with broken or severely worn piston rings

Q6. Discuss the consequences of failure to maintain correct clearances in the case of main diesel engine crankshaft and bottom end bearings. Sketch a bottom end bearing paying particular attention to the arrangement of ensuring uninterrupted flow of oil to the top end bearing. (16)