MEO CLASS IV ORAL QUESTIONS WITH ANSWERS (Part-1)

Q: WHAT IS CAMBER?

ANS) The camber is a measure of lateral main deck curvature in naval architecture.

The practice of adding camber to a ship's deck originated in the era of small sailing ships. These vessels were built with the decks curving downwards at the sides in order to allow water that washed onto the deck to spill off.

Q:WHAT IS TUMBLEHOME?

ANS)In ship designing, the tumblehome is the narrowing of a ship's hull with greater distance above the water line. Expressed more technically, it is present when the beam at the uppermost deck is less than the maximum beam of the vessel.

A small amount of tumblehome is normal in many designs in order to allow any small projections at deck level to clear wharves (structure on the shore of a harbor where ships may dock to load and unload cargo or passengers)

Length overall (LOA) is the extreme length from one end to the other.

Length at the waterline (LWL) is the length from the forward most point of the waterline measured in profile to the stern-most point of the waterline.

Length Between Perpendiculars (LBP or LPP) is the length of the summer load waterline from the stern post to the point where it crosses the stem.

Beam or breadth (B) is the width of the hull. (ex: BWL is the maximum beam at the waterline)

Depth or moulded depth (D) is the vertical distance measured from the top of the keel to the underside of the upper deck at side.

Draft (d) or (T) is the vertical distance from the bott om of the hull to the wate rline.

Freeboard (FB) is the difference between Depth and draft

Q: EXPLAIN MOULDED BREADTH, MOULDED DEPTH, AND DRAUGHT?

ANS)Breadth (extreme):

The extreme breadth, recorded in meters to two decimal places. This is the maximum breadth to the outside of the ship's structure.

Breadth (moulded):

The moulded breath, recorded in meters to two decimal places. This is the greatest breadth at amidships from heel of frame to heel of frame. This will only be displayed when breadth extreme is not available.

Moulded Depth:

The moulded depth, recorded in meters to two decimal places. This is the vertical distance at amidships from the top of the keel to the top of the upper deck beam at side.

Draught:

The draft (or draught) of a ship's hull is the vertical distance between the waterline and the bottom of the hull (keel), with the thickness of the hull included; in the case of not being included the draft outline would be obtained. Draft determines the minimum depth of water a ship or boat can safely navigate. The draft can also be used to determine the weight of the cargo on board by calculating the total displacement of water and then using Archimedes' principle. A table made by the shipyard shows the water displacement for each draft. The density of the water (salt or fresh) and the content of the ship's bunkers have to be taken into account. The closely related term "trim" is defined as the difference between the forward and after drafts.

Q: WHAT IS RECENT AMENDMENT TO SOLAS WITH RESPECT TO MSDS, LIFEBOAT & ETA?

ANS) MSDS: MATERIAL SAFETY DATA SHEET: DATE OF ENTRY IN FORCE: 01-JULY-2009

AMENDMENT OF OCTOBER 2007 TO SOLAS: -

Amendment to SOLAS chapter 6, to add new regulation 5-1 on material safety data sheet (MSDS) to require ships carrying MARPOL Annex 1 cargo (oil) & also marine fuel oils to be provided with material safety data sheet prior to loading such cargoes. The regulation refers to the Recommendations for material safety data sheet (MSDS) for MARPOL Annex 1 cargoes & marine fuel oils, adopted by the organization through resolution MSC 150 (77)

Prevention of accidents involving lifeboats: -

An amendment to SOLAS regulation III concerns provisions for the launch of free-fall lifeboats during abandon-ship drills. The amendment will allow, during the abandon-ship drill, for the lifeboat to either be free-fall launched with only the required operating crew on board, or lowered into the water by means of the secondary means of launching without the operating crew on board, and then maneuvered in the water by the operating crew. The aim is to prevent accidents with lifeboats occurring during abandon-shipdrills. The amendment is expected to enter into force on 1 July 2008.

Q: WHAT ARE THE SAFETY FEATURES IN AIR COMPRESSORS?

ANS)Every Air compressor on a ship is fitted with several safety features to avoid abnormal and dangerous operational errors of the equipment. If safety, alarms and trips are not present on the air compressor, abnormal operation may lead to breakdown of the compressor and may also injure a person working on or around it.

1.Relief valve: Fitted after every stage to release excess pressure developed inside it. The setting of the lifting pressure increases after every ascending stage.

2.copperBursting disc:A bursting disc is a copper disc provided at the airside of the compressor. It is a safety disc, which bursts when the pressure exceeds over the pre- determined value.

3.Fusibleplug:Generally located on the discharge side of the compressor, it fuses if the air temperature is higher than the operational temperature. The fusible plug is made up of material, which melts at high temperature.

4.Lube Oil low-pressure alarm and trip:If the lube oil pressure goes lower than the normal, the alarm is sounded followed by a cut out trip signal to avoid damage to bearings and crank shaft.

5.Water high temperature trip:If the intercoolers are choked or the flow of water is less, then the air compressor will get over heated. To avoid this situation high water temperature trip is activated which cut offs the compressor.

6.Water no-flow trip:If the attached pump is not working or the flow of water inside the intercooler is not enough to cool the compressor then moving part inside the compressor will get seized due to overheating. A no flow trip is provided which continuously monitor the flow of water and trips the compressor when there is none.

7.Motor Overload trip:If the current taken by motor during running or starting is very high then there is a possibility of damage to the motor. An overload trip is thus fitted to avoid such situation

8.High Air Temperature Trip