EKG-Mar-21

Q1. As a second engineer on board a tanker, describe the procedure for presenting the Main Boiler for survey by a classification society.

Q2. How the ingress of seawater is prevented in an oil-lubricated stern bearing system. Should the system fail, describe the corrective action possible whilst the vessel is afloat? State the reasons for fitting two stern bearing oil header tanks in some cases?

Q3. With respect to windlass and deck machinery:  

(a) Describe the principle of coil-operated brake suitable for winches and other deck machinery. 

(b) Explain with suitable sketches how the windlass is relieved of strain when riding at anchor.

Q4. A. State the laboratory tests that may be carried out on specimens of steel for ships’ plates giving reasons for the tests. 

B. The basic compositions of two ships’ plates are given in Table below one is an example of modem practice whilst the other is a specification of a 1940’s tanker that split in two due to brittle fracture. Compare these two specifications critically and explain which of these two steels would be most resistant to brittle fracture.

Q5. With respect to tankers describe: 

A. How a pump room and cargo tanks are ventilated? 

B. The main problem of carrying liquefied natural gas. 

C. How the boil-off from liquefied natural gas is handled?

Q6. A. Explain the necessity of intercoolers on a multi-stage compressor. What attention is required to keep them safe and in good working order? Sketch and describe an intercooler suitable for a 2400kpa compressor and state materials used. 

B. What attention is needed before opening up for inspection? 

C. What faults are likely to develop in an air compressor and how are they remedied.

Q7. A rudder of a vessel requires extensive welding repairs and as Second Engineer you are requested to supervise the repairs. 

A. Suggest a suitable type of welding process; 

B. State, with reasons, FOUR common welding defects. 

C. State what tests may be carried out before returning the rudder to service.

Q8. With respect to refrigeration gases used on-board vessels, answer the following: 

A. Explain the Ozone Depleting Potential (ODP) and Global warming potential (GWP) of conventional refrigerant gases.

B. Name the alternate refrigerant gases available and being used onboard.

C. What steps are taken to minimize the release of refrigerant gases from the plant during normal operation and maintenance activities?

Q9. A. Reverse osmosis is one of the alternatives for shipboard production of drinking water. sketch a simple diagram and describe the principle of reverse osmosis. B. Sketch a line diagram showing a single pass system for producing freshwater from seawater and Describe such a system.