FUNCTION 3

KOCHI CENTRE MARCH 2015 Mr SUBRAMANAM

(1)Sketch the CO2 line diagram, showing the location of relief valve. What is the time delay for the gas to enter the machinery space when released.

Answer:

The location of the relief valve is on the main manifold just after the battery of bottles and is located in the CO2 room.

The purpose of the safety or relief valve is to provide a relief against accidental triggering of the system when the main master valve is shut, to prevent damage to the pipeline.

The regulation for delay period is 85% of the gas should be released in the machinery space within 2 minutes.

(2) Explain the purpose of inclining experiment. What are the precautions needed to be taken for the experiment.

Answer:- The main purpose of the inclining experiment is to determine the KG and LCG of the new ship after completion of construction as well as fitting out in a condition ready to proceed to sea. It therefore determines the KG and LCG of the light ship.

The precautions necessary aare as follows:

* the weather must be calm so there is no movement of the ship caused by the water.

* The mooring lines must be slack to allow ease of heeling.

*There should be no loose unaccounted weights on the ship.

* All Db tanks, f/w tanks and Bunker tanks including lub oil tanks to be empty. The auxiliary boiler, exhaust boiler and the c/w jacket of the engines and auxiliary engines should be dry

* very few personnel on board, only those essential for the conduct of the experiment to be on board.

(3) What determines the expansion ratio of foam used for fire fighting. What should be the expansion ratio for foam used on the decks. What is the expansion ratio of high expansion foam and where is it used

Answer:- The principle of foam generation is reduction of the surface tension of the foam compound/water solution with introduction of air . The foam thus obtained forms a blanket on the fire cutting of air supply to the fire and thus extinguishing the fire.

The combination ratio determines the foam expansion ratio. In tankers the low foam expansion is used for spreading on decks upto a depth of 15cms of foam. Such a foam is called low expansion foam made by mixing 12 parts of water (sea) with 1 part of foam compound

High expansion foam is generated by blowing air through a mesh which has been wetted by a solution of foam concentrate in water . It has been used for hold protection on some container vessels and has been tested for engine room fire fighting.

The mesh is corrugated and its hole size governs the expansion ratio of the foam which is limited to 1000:1 by regulation. The limit is required because the foam is composed largely of air and easily break down when in contact with a fire. Composed , in the 1000:1 foam, the original 1 volume of liquid evaporated and produces enough steam to reduce the percentage oxygen in the steam/air mixture to about 7.5%. This amount of oxygen is below the level normally required for combustion. Heavier high expansion foam can be produced with a different mesh size.

The foam concentrate is metered or mixed with water to given a 1.5% solution of concentrates in water ,and sprayed on the screen. Air is blown through by an electrically driven fan( water pressure drives have been used). Delivery ducts are necessary to carry the foam to the fire area Generation of foam must be rapid and sufficient to fill the largest apace to be protected at the rate of 1 meter (depth)/minute. (4) what is an observation and non-conformity in ISM code.

Answer:- Non Conformity :When objective evidence indicates non fulfilment of a specific requirement stated by the safety management system, a situation of non conformity is considered to have occurred.

Observation means a statement of fact made during a safety management audit and substantiated by objective evidence

(5) What is meant by angle of loll and how is it to be corrected. What type of ships experience angle of loll.

Answer:-The angle of loll is the stable heeled angle reached by a ship with very small GM (height). In this condition a small swell or a squall of wind can easily tip the ship so it heels over to the other side and comes to rest at the angle of loll on the other side

To increase the transverse stability of the ship or improve the GM, weights must be added at the bottom to make the G go down and this is done by ballasting its DB tanks.

Normally passenger ships which are top heavy , because of the number of decks above the freeboard deck, as well as car carriers are subjected to this condition.

(6) Explain in your own words what is the purpose of ISM code and how is the ships operation made safer and pollution free.

Answer:- The ISM code was introduced in the year 1995 and with a with a protocol that by 31st july 1998 all existing ships should comply by this code . This code is an operational code devised for all personnel on the ships as well as the shore establishments to follow a committed system of safety and pollution free operation of the ships they control and manage.

To reach these objectives which are:

*Safety at sea

Prevention of human injury or loss of life

Prevention of damage to environment or pollution of environment

Preparing the ships personnel for emergencies,

The personnel involved have declared responsibilities which are documented and observed in their day to day work and finally audited at regular intervals by the administration and /or classification societies

One worthy feature of this code is the recording of near misses and accidents on the ship and analysing their causes to prevent future recurrence of similar situations.

(7) What is the purpose of the stability booklet. List out the information the stability booklet is provided with.

Answer: The stability booklet is aship special document which gives all the stability particulars of the particular ship so that the Master and other officers concerned in the operation of the ship can safely carry out the functions of loading, stowing cargo and ballasting of the ship so that the voyage is executed safely and confidently.

For this purpose the stability booklet is provided with the following tabulated information:

(1)Displacement

(2)C.B. below designed W.L.

(3)C.B. abaft/ fwd amidships.

(4)C.F. abaft/fwd amidships

(5)Transverse metacentre above designed W.L.

(6) Tonnes per cm immersion.

(7)Longitudinal metacentre above designed W.L.

(8) Moment to change trim 1 cm

Tabular statements for the cross curves of stability :* The KM values for angles of heel 00,150,300,450,600,750 and900 at summer draft, tropical draft and ballast draft.

If it is a self trimming bulk carrier , grain shift moments for all holds in tabular format.

At least four to six worked examples of cargo types loading , giving the initial GM, trim condition with drafts forward and aft.

The GZ curves of statical stability for departure and arrival condition.

One of the worked examples will be the ballast condition.

The data and results of the inclining experiment will also be included in the annexe.

Apart from this information if it is a B-60 or B-100 Bulk carrier , the working and result of the damage stability condition will be given.

Mr Sudarshan

(8) What is the difference between security level 2 and 3. What is the responsibility of the 2nd engineer when receiving stores during security level 2.

Answer:- Security level 1: normal, the level at which the ship or port facility normally operates. Security level 1 means the level for which minimum appropriate protective security measures shall be maintained at all times.

Security level 2: heightened, the level applying for as long as there is a heightened risk of a security incident.Security level 2 means the level for which appropriate additional protective security measures shall be maintained for a period of time as a result of heightened risk of a security incident.

Security level 3: exceptional, the level applying for the period of time when there is the probable or imminent risk of a security incident.Security level 3 means the level for which further specific protective security measures shall be maintained for a limited period of time when a security incident is probable or imminent, although it may not be possible to identify the specific target.

From the descriptions of security level 2 and security level 3, as given in the code, it can be seen that security level 3 is more severe and hence needs more monitoring and concentrated awareness than security 2

The second Engineer should avoid receiving stores during security level 3 unless it is absolutely essential.

During security level 2 the second engineer should first check and verify the credentials of the delivery man bringing the stores. This could be by checking his identity card and the companys letter or delivery note.

The stores should be examined at a safe distance near the jetty and can be brought in after they have been examined and proved safe for acceptance.

(9) What are the equipment in engine room which require inspection under MARPOL surveys and certification.

Answer:- (1) The working of the oily water separator and the oil monitoring instrument working should be demonstrated to the surveyor for its proper functioning.

(2) The proper functioning of the incinerator should be demonstrated to the surveyor.

(3) The oil record book part 1 will be scrutinised by the surveyor to check all the entries made and verify their correctness.

(4) Collection and disposal of oily rags and incinerato(10 ) What is the purpose of stability booklet and what information does it provide to the master.

Answer:- Repeat question. Refer Question (7) KOCHI centre.

(11) Explain by a diagram how the rudder works.

Answer:- The shape of any ship is symmetrical about the longitudinal centre line along the length of the ship. This property gives equal distribution of the wake on both the sides of the centre line , thus providing directional stability when moving ahead. In addition the main engine and the auxiliary engines provide gyroscopic stability due to the angular momentum of the rotational mass of the engines in the ahead direction adding to the directional stability stated earlier . Referring to the diagram it can be seen that when the rudder is placed to the port side, the perpendicular water force acting on the centre of pressure of the rudder provides a port torque on the hull which tends to turn the ship to the port side. Similarly if the rudder is turned to the starboard side the ship will turn to the star board side. This is how the rudder turns the ship to the direction required.

(12 ) List the statutory certificates a ship is provided along with their validity and the act or convention under which it is issuedAnswer:- The list of statutory certificates and their validity

No

Title

Validity

Convention

1

Registration certificate

Permanent till change of flag or scrapped

M.S. Act

2

Tonnage

Permanent

Tonnage Convention 1969

3

Safety Equipment Certificate

5 Years

SOLAS Chapter II & Chapter III

4

Safety Construction certificate

5 Years

SOLAS Chapter II, III, V

5

Cargo Ship Safety Radio Certificate

5 Years

SOLAS Chapter IV

6

IOPP

5 Years

MARPOL Annexure I

7

ISPP

5 Years

MARPOL Annexure IV

8

IAPP

5 Years

MARPOL Annexure VI

9

ENERGY efficiency certificate

5 years

MARPOL Annexure VI

10

SAFE Manning

5 Years

SOLAS Chapter IX

11

ISM

5 Years

SOLAS Chapter IX, ISM Code

12

DOC (True Copy)

5 Years

-Do-

13

ISPS

5 Years

SOLAS CH XI-2

(13 ) What are the regulations prescribed for the CO2 pilot bottles.

Answer:- The CO2 pilot bottles are similar in construction to the storage bottles and the same regulations for manufacture of the storage bottles apply.

The bottles are made of solid drawn steel, hydraulically tested to a pressure of 22.8 bar. The bottles are fitted with a quick release type valve commonly called Klem valves, in which the combined seal and bursting disc is pierced by a cutter for release of the gas when the system is triggered.

(14) Explain the annual maintenance of foam equipment.

Answer:- The following maintenance activities shall be carried out at regular intervals as prescribed in the equipment manual.:

* the foam lines with their isolation valves will be tried out by pumping sea water through them. Leaky isolation valves will be dismantled and overhauled by renewing damaged parts. The foam lines if found leaking will be renewed suitably by same pipe material.

* the pumps will be tried out and if deficient in maintaining the prescribed head will be dismantled and suitably repaired by renewing damaged parts of the pump.

* The foam concentrate sample and water will be combined in the prescribed proportion in a measuring cylinder of glass to check if the expansion ratio is correct.

* If the foam concentrate has lost its strength, the same will be renewed.

(15) Why is the rudder placed aft and not forward.

Answer:- In a ship the maximum strength and intensity of the wake is in the proximity of the propeller. Since the propeller is placed aft , the rudder should also be placed aft close to the propeller so that the full intensity of the wake hits the rudder to make the rudder turn the ship effectively and fast.

If the rudder is placed forward it will make the ships turn very sluggish.

Mr SUBRAMANIAM and Mr AJITH. JAN 2015

(16)What is GWP.

(17) List the safeties provided in the IG system.

Answer:- The safeties provided in the IG system are:

Excess O2 in inert gas alarm and cut out.

Deck seal and low water alarm in deck seal.

Blower trip alarm. And signal light.

Low water level alarm in scrubber unit.

High water level alarm in scrubber unit.

P/V breaker

Low inert gas pressure alarm and light (18) What is IBC code. What ships are built under this code.

Answer;- International Bulk Chemical Code (IBC Code)

The International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk. The IBC Code contains theIMOregulations that govern the design, construction, and outfitting of new built or converted chemical tankers. The IBC Code replaced the Code for the Construction and Equipment of Ships Carrying Dangerous Chemical in Bulk, which applies to chemical tankers built or converted before 1 July 1986

(19) Sketch the p/v valve and explain its working.

Answer:-Pressure/ Vacuum valves attached to tank vents will prevent either under or over pressure over a range of 0.14 bar so that the distortion of the deck plating is avoided. Pressure/ vacuum valves can relieve moderate changes in tank pressure due to changes in temperature and vapour quality.

(20)What is the difference between OWS and ODM.

Answer:- OWS is oily water separator .It is the equipment in the machinery space of all ships which separate oil from bilge water in accordance with the provisions of MARPOL annexe 1.

ODM is oil discharge monitor. It is the monitoring device fitted on the tanker cargo system to monitor the oil discharged into the sea when discharging the contents of slop tanks so that the oil discharged is within the 30 litres per nautical mile limit in accordance with MARPOL annex 1

(21) What are fire protection Bulkheads and how are they classified.

Answer:- The fire protection bulkheads are basically of two types (1) A class made by steel combined with a non combustible fibre material and (2) B class made by non combustible material only.

A class:- Divisions are those divisions formed by bulkheads and decks which comply with the following criteria:

1.They are constructed of steel or other equivalent materials;

2.They are suitably stiffened;

3.They are insulated with approved non-combustible materials such that the average temperature of the unexposed side will not rise more than 1400c above the original temperature, nor will the temperature, at any one point, including any joint, rise more than 1800c above the original temperature, within the time listed below:

Class A-60 60min

Class A -30 30min

Class A-15 15min

Class A-0 0 min

4. They are so constructed as to be capable of preventing the passage of smoke and flame to the end of the one-hour standard fire test.

B class:

1. They are constructed of approved non-combustible materials and all materials used in the construction and erection of B class divisions are non-combustible, with the exception that combustible veneers may be permitted provided they meet other appropriate requirement of this chapter;

2. They have an insulation value such that the average temperature of the unexposed side will not rise more than 1400c above the original temperature, nor will the temperature at any one point, including any joint, rise more than 2250c above the original temperature, within the time listed below;

Class B -15 15min

Class B - 0 0 min

3. They are so constructed as to be capable of preventing the passage of flame to the end of the first half hour of the standard fire test

(22) Explain the function of management review.

Answer:- In the ISM code the management review meeting is conducted at least once every year before the annual internal audit and chaired by the master of the ship.

The Agenda for this meeting is as follows:

Review of progress made in the SMS(safety management system)

Review of recurring near misses and suggested corrective action/s

Review of conduct of emergency drills.

Review of pending essential stores and spares supply.

Any other matter pertaining to safety and pollution prevention.

. (23) Explain the objectives of ISM code and how they are attained

Answer:- The objectives broadly stated are: *Safety at sea

Prevention of human injury or loss of life

Prevention of damage to environment or pollution of environment

Preparing the ships personnel for emergencies,

The personnel involved have declared responsibilities which are documented and observed in their day to day work and finally audited at regular intervals by the administration and /or classification societies

One worthy feature of this code is the recording of near misses and accidents on the ship and analysing their causes to prevent future recurrence of similar situations.

(24) What is NOX code.

Answer:- The revised NOx Technical Code 2008 includes a new chapter based on the agreed approach for regulation of existing (pre-2000) engines established in MARPOL Annex VI, provisions for a direct measurement and monitoring method, a certification procedure for existing engines, and test cycles to be applied to Tier II and Tier III engines.

Revisions to the regulations for ozone-depleting substances, volatile organic compounds, shipboard incineration, reception facilities, and fuel oil quality have been made with regulations on fuel oil availability added.

The revised measures are expected to have a significant beneficial impact on the atmospheric environment and on human health, particularly for those people living in port cities and coastal communities.

(25) What are the contents of the NOX technical file.

Answer:- The NOX technical file is based on the code for conducting the trials in accordance to Annex 6 chapter 4 REG 20 and. 21 of MARPOL. The purpose of the Code is to specify the requirements for the testing, survey, and certification of marine Diesel engines to ensure they comply with the NOX emission limits as of Regulation 13 of Annex VI of the MARPOL regulations and the corresponding tier applicable table. In order to achieve repeatable and comparable results for the assessment of an engines emission behaviour. Tests must be performed on the applicable test cycle under defined reference conditions and using standardised exhaust gas measurement methods as described in Appendix III of the Code. Other engine parameters than exhaust gas components like engine power, temperatures, pressures etc. need to be measured with prescribed accuracy. The measurement results need to be documented in a test report which shall include also the calculated specific emissions of all relevant individual exhaust gas components, as The measurement results need to be documented in a test report which shall include also the calculated specific emissions of all relevant individual exhaust gas components, as calculated as the weighted average emission value, using the weighting factors of the applicable test cycle. The set of data provided in this document may be used to verify the proper calculation of any self programmed calculation software against the results listed and commented.

The test results are available in the NOX technical file (26) Explain the code for safe containers.

Answer:- International Convention for Safe Containers (CSC)

Adoption: 2 December 1972; Entry into force: 6 September 1977

In the 1960s, there was a rapid increase in the use of freight containers for the consignment of goods by sea and the development of specialized container ships. In 1967, IMO undertook to study the safety of containerization in marine transport. The container itself emerged as the most important aspect to be considered.

IMO, in cooperation with the Economic Commission for Europe, developed a draft convention and in 1972 the finalized Convention was adopted at a conference jointly convened by the United Nations and IMO.

The 1972 Convention for Safe Containers has two goals.One is to maintain a high level of safety of human life in the transport and handling of containers by providing generally acceptable test procedures and related strength requirements.The other is to facilitate the international transport of containers by providing uniform international safety regulations, equally applicable to all modes of surface transport. In this way, proliferation of divergent national safety regulations can be avoided.

The requirements of the Convention apply to the great majority of freight containers used internationally, except those designed specially for carriage by air. As it was not intended that all containers or reusable packing boxes should be affected, the scope of the Convention is limited to containers of a prescribed minimum size having corner fittings devices which permit handling, securing or stacking.

Technical annexes

The Convention includes two Annexes:

Annex I includes Regulations for the testing, inspection, approval and maintenance of containers

Annex II covers structural safety requirements and tests, including details of test procedures.

Annex I sets out procedures whereby containers used in international transport must be safetyapproved by an Administration of a Contracting State or by an organization acting on its behalf.

The Administration or its authorized representative will authorize the manufacturer to affix to approved containers a safety approval plate containing the relevant technical data.

The approval, evidenced by the safety approval plate granted by one Contracting State, should be recognized by other Contracting States. This principle of reciprocal acceptance of safetyapproved containers is the cornerstone of the Convention; and once approved and plated it is expected that containers will move in international transport with the minimum of safety control formalities.

(27) what are the safety approval plate details.

Answer:- the details given in the safety approval plate are the following:

*The name of the contracting state which has conducted the various tests for approval.

* the date of testing and year of manufacture.

* The name of the authority or approved body witnessing the tests

* The seal of the witnessing body or organization.

* the seal of the contracting state. (28) How is the economic speed of the ship determined.

(29) How is low sulphur fuel oil, graded and what are the problems associated with it.

Answer:- The low sulphur fuels as per MARPOL annex six are the specified low sulphur content fuels namely the 1.5%, 1% and 0.1 % sulphur content fuels prescribed for tier 1,2 and3 respectively .

Although they reduce the pollution effect on the atmosphere, the operational difficulty is changing over the relevant recommended cylinder oil. Frequent change over of the fuel oil from open sea condition to SECA areas sulphur content fuel oils can cause inadequate alkalinity or neutralizing quality in the cylinder lubrication requirements , which can lead to either corrosion of the liner surface or caustic embrittlement of the liner surface.

Mr MURALI JAN 2015

(30) Explain the following terms:

Double Bottom., Sheer strake, Garboard strake. and Shell Expansion plan.

Answer:-Double bottom is the space contained between the bottom plating and the inner bottom plating of the hull. This space is subdivided into tanks for the purpose of storage of ballast water, fresh water and/pr bunkers including lub oils.

The double bottom space is strengthened by floors(transverse) and intercostals(longitudinal). The storage space helps in improving the transverse stability by bringing the G of the ship more down , thereby improving the GM.

Sheer Strake: the top most ship side strake or plate of the hull. It is called sheer strake because it follows the deck sheer line.

Garboard Strake:- It is the strake adjacent to the keel strake at the bottom of the hull , one on the port side and another on the starboard side.

Shell expansion plan:- It is a two dimensional drawing of a three dimensional surface of the ships hull form. It is developed from the ships line plan with the contour lines erected straight on the base line representing the ships length. The contour lines on the lines plan are located at corresponding stations indicated by corresponding frame numbers on the length of the base line. When the ends of the vertical lines on the baseline are joined by a continuous line , the shell expansion outline is obtained. The represented surface is then properly marked by parallel lines both vertical and horizontal lines so that they correspond exactly to the number of strakes forming one half of the hull surface. The strakes are marked with letters A,B,C ,etc vertically starting from sheer strake as strake A and ending with keel as strake R eg. The strake numbers are staring from 1 at the stern end to any ending number at the forward bow. Each strake is there fore indicated by a letter to show its level , a number to show its position .

This plan is very useful for the following information:

(a) It is used for marking the location of a hull

Damage on this plan by identifying the strake number , letter and frame number so that the exact location of the damage and also suggested repairs are marked in a localised copy.

(b)The shell expansion can be used for finding areas of painting surfaces such as topside, boot topping and bottom areas by applying Simpsons rules directly. In the shell expansion the vertical scale used is different from the horizontal scale and a suitable adjustment has to be made when calculating areas.This becomes useful in solving disputes concerning areas of preparation and painting.

(c) It gives information on the thickness of the original strake which is indicated by the number in the circle shown in the strake. The quality of steel used is also shown by letters A,B,D E and AH, BH,DH, EH

(31) What is frame spacing and frame numbering.

Answer:-Frame spacing indicates the pitch of the side frames, which is made equal in the middle length of the ship, especially the parallel body length. In the fore part and aft part of the hull the frame spacing or pitch is reduced equally for providing local strength against pounding.

The numbering of frames from aft perpendicular to the forward perpendicular is done for identification of location in describing any structural defect or repair. It therefore provides as a location marker equivalent to longitude in geography.. The frames forward of the fore perpendicular are numbered +1 , +2,+3---and so on from fore perpendicular to extreme forward. The frames aft of the aft perpendicular are marked-1 ,-2,-3 -----and so on from the aft perpendicular to the extreme aft end.

(32) What are the safeties provided on the CO2 system. What is the purpose of the relief valve in the system. What is the time delay between release and entry of gas into the machinery space.

Answer:- The safeties provided in the CO2 permanent installation are:

The operating controls are properly secured so that misuse or accidental operation is avoided. The main stop valve control and the pulling device for triggering the system are placed in a steel cabinet under lock and key with a glass window so that even when locked the glass can be broken and the cabinet opened.

The provision of the relief valve in the CO2 room to relieve accidental pressurising of the CO2 manifold.

All the bottles are stowed safely in the vertical position and clamped by dismantable clamps . This provides safety against accidental release in bad weather in case the ship rolls heavily.

The bottles are placed on wooden gratings to avoid water logging in the room and hence prevent corrosion of the bottles bottoms.

The room is fitted with an automatic exhaust blower to ventilate the room in case the room is flooded accidently by released CO2. The auto switch is connected to the door , so that on opening the door the blower starts operating.

Purpose of Relief valve:-Bottle pressure is normally about 52 bar but this varies with temperature.Bottles should not be stored where the temperature is likely to exceed 550 C. The seal/ bursting discs are designed to rupture spontaneously at pressures of 177bar produced by a temperature of about 630 C . The Master valve prevents CO2 released this way from entering the machinery space..Gas is released by the relief arrangement on the manifold, into the CO2 space where, in the event the release was caused by fire in the compartment , the fire would be extinguished.

The time delay from release of gas to the time it enters the machinery space is two minutes during which time 85 percent of the total gas is released in the machinery space

(33) What is the difference between statical and dynamical stability.

Answer: For a ship to be statically stable the initial metacentre M in the upright condition is above G . Its measure is the length GM in the upright condition. Factually speaking the transverse metacentre does not exist at the upright condition. But for small angles of heel up to 60 and as per the mathematical limit theorem the sin of the angle of heel is the same as the angle of heel up to 60 . Hence the initial metacentric height is considered the same upto 60 on either side of the vertical.

Dynamical stability is the ability of a ship to return to the original upright condition when made to heel by a passing side swell or squall of wind ,after they have passed over

The measure of dynamic stability is the area under the GZ curve from zero degrees to the angle of heel given in KN meters. The angle of heels have to be considered in radians.

(34) What is damage stability criteria. For tankers under MARPOL and for bulk carriers under L/L Regulations.

Answer:- For tankers the damage stability criteria in general terms and as per design are as follows:

Cargo tanks shall be of such size that the maximum hypothetical outflow is restricted ranging from 30000 M3 (minimum) to 40000M3 (maximum) proportional to the size of the tanker.

The volume of any one wing cargo tank shall not exceed 75% of the hypothetical outflow as stated above.

The volume of any one centre tank shall not exceed 50000M3

In order not to exceed the volume limits as stated above, irrespective of the cargo transfer system, closing devices shall be fitted for separating the tanks from each other. These valves or devices shall be closed when the tanker is at sea.

The stability criteria under the above conditions are as follows:

The initial intact stability transverse GM shall not be less than 0.15M (6ins)

When damage takes place the damage stability criteria are as follows:

The final water line , taking into account sinkage ,heel and trim , shall be below the the lower edge of any opening such as air pipes vents, weather tight doors, hatch covers.

In the final stage of flooding , the angle of heel due to unsymmetrical flooding shall not exceed 250, or 300,if no deck edge immersion takes place.

The stability in the final stage of flooding shall be investigated and may be regarded as sufficient if the righting lever curve has at least a range of 200 beyond the position of equilibrium and a maximum residual righting lever of at least 0.1m within the 200 range. The area under the GZ curve within this range shall be not less than 0,0175 m-rad.

For DRY BULK CARRIERS

The damage criteria and stability criteria are as follows:

Dry cargo ships of over 100 metres in length, when loaded up to summer draught, will remain afloat in a satisfactory condition of equilibrium after flooding of any single damaged compartment at an assumed permeability of 0,95 excluding the machinery space. In such ships the freeboards shall be reduced to not more than 60% of the difference between table A and table B for the same length of ship.

B-100:- In dry cargo ships of over 225 metres in length, the machinery space will be treated as a floodable compartment with an assumed permeability of 0,85. The ship will remain afloat in a satisfactory condition of equilibrium after flooding of any single damaged compartment with assumed permeability 0,95 and the machinery space with assumed permeability of 0.85.In such ships the freeboards shall be reduced to not more than 100% of the difference between table A and table B for the same length of the ship

The stability criteria is as follows:

The final water line after flooding is below the lower edge of any opening through which progressive flooding may take place

The maximum angle of heel due to unsymmetrical flooding is of the order of 15 degrees.

The metacentric height in the flooded condition is positive.

(35) Sketch the rudder carrier bearing and how is the bearing wear down measured.

Answer:-

The rudder carrier bearing wear down can be accurately measured , if the clearances at bottom at the trunion cross head bearing is measured and recorded at every dry docking

In most cases the wear down is negligible and hence the wear down is checked using the trammel gauge to confirm there is no wear down

However for accurate gauging the clearance at the trunion cross head of the steering rams connection should be taken and recorded at every dry docking. And this is shown in the sketch shown under.

If the clearance at the bottom on the crosshead is Y then

Y = present wear reading and

Y1 = last Dry dock wear reading, then

Y---Y1 is the present wear down.

(36) How is an enclosed space made fit for safe entry. What is the method of calibration of the oxygen meter.

Answer:- The method of making an enclosed space fit for man entry is as follows:

The space is to be opened and most probably it will be a man hole door. After opening the door. The space is to be ventilated by using a portable blower and forcing air into the space through the man hole, for at least 8 to 12 hours. The air is exhausted through the air pipe fitted in the space.

Progressively the space oxygen content should be measured by lowering the meter or the sample suction pipe into the space and taking readings of the oxygen content.

If the tank or space is well spread out it may be necessary to enter the space with breathing apparatus (SCBA) to note the oxygen content.

Any water if found in the space must be pumped out to make entry safe.

Entry may be permitted when the oxygen level is atleast 21% by volume.

Accurate calibration is done by using pure nitrogen sample for 0% oxygen and sample air from open space for 21% oxygen content

(37) Draw the cross section of a Bulk carrier and identify the keel plate in it. What is a frame.

(KEEL PLATE) Answer:-

The frame is the hull side stiffener and is indicated in the sketch shown above as side frame. It strengthens the side shell plating of the hull.(38) What is a keel block. How to decide the number of keel blocks to be used and their position.

Answer :- The keel block is the support wood on steel block placed under the keel when the ship is being docked(dry dock).

When ever the ship is being docked, the docking is done with the guidance of the docking plan which is ship specific and available on every ship The docking plan suggests the arrangement of the blocks

For guidance the sketch of the docking plan is given under (39) What is frame and frame numbering.

Answer:- Repeat question . Refer to question number (31)KOCHI centre(40) How to identify the strake to be renewed and how it is to be ordered, for repair in dry dock.

Answer:- During Dry docking, the shell expansion is referred to for identifying the renewal of hull plating . The portion of the plate to be renewed is first marked by paint. The frame number /s which is covered by the plate is identified on the shell expansion by counting the frame number from aft or forward perpendicular. The stake marked on the shell expansion plan will have the class of steel and the thickness will be indicated on a circle within the strake . Hence the plate can be correctly ordered by the ship yard for renewal.

(41) If the wear limit of the rudder carrier bearing is attained, what repairs are carried out to bring the bearing to original condition.

Answer:- When the rudder carrier bearing has worn down to its limits, the bearing halves of the fixed and moving portions are to be dismantled and sent for building up of the bearing faces by welding and then suitably machined. The bearing halves are made of cast steel and hence can be welded and machined as required. The procedure is as follows:

The ram cross head connections are dismantled so that the tiller is free of the cross head and the stock can be pushed up along with the tiller.

The rudder is supported on an appropriate hydraulic jack and lifted sufficiently so that the carrier bearing halves can be dismantled. The moving halves are keyed to the stock and fitted by bolts which can be dismantled and removed. The fixed halves are bolted to the transom deck and can be removed by dismantling the bolts

After building up the halves by welding , they are machined smooth to the original thickness or height and the same taper. There are grease gutters radially spaced for spreading grease between the faces of contact. These gutters are to be maintained whilst building and machining the halves..

The fixed halves are fitted on the transom deck and the moving halves on the stock with the key in place.

The stock and rudder are lowered by gradually lowering the jack. The jack is removed and the rams connected at the cross head.

The clearances X and Y at the top and bottom at the cross head connection must be measured and recorded for future reference for assessing the wear (42) Draw the fixed foam system line diagram . What is expansion ratio .

Answer:-

A flexible foam liquid induction unit used in many tankers to supply deck foam-monitor equipment ,is shown in the figure above. The automatic inductor on the suction side of the pump maintains the appropriate foam liquid quantity in the water stream. Water pressure and foam liquid suction ports are provided at the side of the automatic foam inductor unit. Water under pressure from the discharge side of the pump enters the pressure port inducing foam liquid from the tank through the foam liquid suction port. A swing paddle fitted in the body of the inductor, in the main water flow moves backward and forward, according to the rate of flow. The paddle rotates a water metering vane in the water pressure port, bypassing water into the foam liquid port, thus diluting the foam, liquid entering the water stream at the correct concentration to meet all flow conditions. The atmospheric type foam liquid tank enables the system to be replenished during operation.

b) Consider a 3% solution which is said to give 200:1 expansion ratio . this is tested by taking a glass measuring cylinder graduated in ml. Take 0.3ml of the concentrate, add 9.7ml of water and shake it. It should expand to 200ml which can be read on the measuring cylinder. So 200:1 or 20:1 means the expansion ratio when a known quantity of water is mixed with the concentrate known quantity to give the expansion.

(43) What are the safeties provided on the ships fire main. What is the purpose of the isolation valve.

Answer:-The safeties provided on the Fire Main of the ship are:

The relief valve on the deck to relieve the pipeline of excess pressure on following occasions;

(1) When the pump is on without any hydrant on deck open

(2) If the shore fire pump or ship yard fire pump is in use through the international shore coupling. These pumps deliver at higher pressure than the GS pump or the FS pump.

(3) If the ships ballast pump is connected to the fire main.

Isolation valves , one at outlet at main deck level from emergency fire pump room and another from exit of engine room at main deck level. These are provided to isolate the portions of pipeline not in use so that full pressure is available on the main by one ships pump.

At least 4 drains provided on the fire main on the main deck. These are to be kept open when the main is not in use , when the ship is north or south of the tropics in winter to prevent damage to the pipeline by water freezing in the main., if not drained. (44) How is the lifeboat engine manually started and how does the decompression lever work.

Answer:- The life boat engine is started by hand cranking the crank shaft with the fuel on and the inlet and exhaust valves decompressed.

Within a few turns of the cranking lever the engine starts. By decompressing the exhaust and inlet valves the engine gains momentum quickly and when the decompression lever is released , the sudden build up of pressure in the cylinder is able to ignite the fuel injected in the cylinder due to the corresponding high temperature attained by the air compressed in the cylinder.

The decompression lever keeps the inlet and exhaust valves open thereby relieving the back pressure in the cylinder so that the required momentum is gained.

In extreme cold weather a spray of benzenegas from an aerosol can will aid in quick starting of the engine.

December 2014 Mr SENTHIL and Mr SUBRAMANIYAM.

(45) What are the stresses acting on the hull structure when the ship is in a seaway.

Answer:-When the ship is floating stand still condition in water,

*The ships light weight acting through the ships CG plus the individual concentrated masses consisting of the various cargoes and liquids on board, acting through their centres of gravity equals the total buoyancy upward force acting through the centre of buoyancy.

* since individually they are not equal nor do they act through the same vertical lines, they give rise to a shear force and a bending moment at every section of the hull along its length.

* When the ship is sailing at sea the buoyancy forces are variable depending on the wave profile and this gives rise to an excess of bending moments and shear forces which lead to heavy straining of the ship longitudinally named hogging and sagging.

* Depending upon the direction in which the bending moment acts , the ship will hog or sag. If the buoyancy amidships exceeds the weight , the ship will hog , and may be likened to a beam supported at the centre and loaded at the ended.

When a ship hogs , the deck plating and girders are in tension while the bottom plating with its intercostals are in compression

If the weight amidships exceeds the buoyancy , the ship will sag , and is equivalent to a beam supported at its ends and loaded at the centre

When a ship saga , the bottom shell is in tension while the deck is in compression.

Repeated hogging and sagging caused by the wave motion can lead to fatigue conditions of the hull plating and in very adverse circumstances fracture of the plating or fatigue cracks at critical locations can occur.

(46) What is hull roughness analysis . How is it carried out.

Answer:- The hull roughness of the ship can be determined by a tool known as hull roughness analyzer or similar instrument for those ship which are not coated with silicon basedfoul release paintcoating.

If the ships hull is coated with silicon based paint, speed trails are done to determine hull roughness which gives changes in the performance and speed of the ship.

Understanding Hull Roughness Analyzer

A Hull Roughness Analyser (HRA) consists of a portable microprocessor along with a digital printout and display unit.

A computer is connected to the hand held carriage having a stylus measuring head.

The stylus head is moved around the hull surface to measure and record the hull roughness profile.

The short wave roughness is the diameter of the stylus tip. The long wave cut off is set at 50 mm.

Working of Hull Roughness Analyzer

One traverse of the head at any point on the hull will collect information from 10 samples having length of 50 mm.

For each 50 mm sample, the micro processor will assess the mean gradient through the peaks and valleys to give highest peak to lowest valley measurement for that sample.

This measurement is known asRt (50).

The roughness check covers approx 100 selected locations which must include bow, stern, mid ship, and boot topping area (area between load line and ballast water line).

A number of traverses for stylus will give n readings, hence the Mean Hull Roughness (M.H.R) at that station is average of

Rt (50) i.e.

M.H.R = Rt(50)/ n

There will be m stations around the hull of the ship. Hence Average Hull Roughness (AHR) will be average of Mean Hull Roughness i.e.

A.H.R= M.H.R/ m

Normal Duration for Analyzing Ships Hull

When the ship is new, beforelaunching the ship, hull surface roughness is checked which become a reference value of that ship.

When the ship comes indry dockand before the maintenance process is started on the hull. This gives the deterioration value.

Before Undocking to measure or compare the hull after maintenance procedure is completed.

Typical Roughness or A.H.R of a ship when it is new is approx 120 microns.

Due to fouling and deterioration, an 8 year old ship will have A.H.R in the range of 300-400 microns.

The significance of the roughness profile is that increase in the hull roughness will increase the frictional resistance of the ship. Since this is the major aspect of resistance for a merchant ship, this will increase the power, fuel consumption and operating cost of the ship. (47 ) Explain the procedure of hull preparation and painting.

(1) Answer:- BOTTOM PREPARATION AND PAINTING AS PER COMPANY S PAINTING SPECIFICATIONS.

This is the first objective in dry docking , commences on the first day and continues till almost to the last day in dry dock. On the first day the areas requiring grit blasting are decided by the superintendent in consultation with the paint suppliers technical officer and the yards painting department manager. The areas where heavy grit blasting are required on an average are as follows :

(a) Top sides about 40% of the total top side area. After grit blasting two coats of primer paint put each coat 30 microns.

(b) The Boot top about 60% of the total belt area consisting of the wind and weather strakes extending from summer load line to L.W.L . After grit blasting to apply two coats of primer paint each coat 40 microns. thick.

(c) On the bottom side the grit blasting area is negligible and at the most does not exceed about 5%. Two coats of primer paint must be applied on the blasted areas.

(d) The full painting specification now as an example is as follows

Top side:- Two coats primer paint each coat 40 microns thick and two coats finish paint, 40 microns thick, each coat.

Boot Top:- Two coats primer paint each coat 40 microns thick, two coats finish paint ,each coat 40 microns thick. Anti fouling paint one coat 40 microns thick.

Bottom:- Two coats primer paint 40 microns thick each coat. Two coats finish paint 40 microns thick each coat. One coat anti fouling paint 40 microns thick.

During the painting process the paint suppliers technical officer checks the coating thickness using a paint thickness gauge which is a strip of plating about 3 mm thick with markings which whilst scrapping the half dried paint indicates the thickness by the thickness noted on the plate gauge.(Refer to Fig. 6). The paint is applied by airless spray nozzles.

The Technical officer also inspects the blasted strakes before the primer paint is applied.

( 48) Sketch the foam proportioner used in the foam making equipment on the ship.

Answer:-

A number of foam concentrates have been developed including protein ,Flouroprotein and aqueous film-forming foam solutions. Some of these have a specific gravity close to that of water.

The foam liquid is stored in a flexible rubber bag within the steel tank. Water by-passed via the venture, feeds into the space between tank and the bag , thus exerting an indirect pressure on the foam liquid and forcing it into the low pressure side of the venturi(49) Describe with a suitable sketch the e-vac sanitary system.

Answer:-

The E-VAC sewage extraction system utilises vacuum to flush the W.C. together with water. By this process the consumption of toilet water is reduced.

The w.c. pan is fitted with a spring loaded flat tray which opens to the drain when loaded with excreta. When the flush valve is operated the water is supplied for flushing as well as creating the vacuum by the educator(convergent-divergent nozzle) which sucks the mixture and transfers it to the holding tank.

The holding tank has a float controlled switch which regulates the transfer of the holding tank content to either the sewage treatment plant or to sea or shore facility as convenient.

In this system the water pressure is kept slightly higher than the normal toilet water pressure. This is required for creating the vacuum as well as for flushing purpose.

(b) The advantages are :

(1) water consumption is greatly reduced.

(2) Since water consumption is reduced the ship can afford to use fresh water for flushing purpose and thereby corrosion of pipes are avoided

(3) More effective sealing of toilets . hence foul odour is avoided.

(50) How is the lifeboat winch brake tested statically and dynamically.

Answer:- The static brake test is preferably done during the renewal survey when the brake falls are renewed

Static Test:- The boat is to be rigged up with its full equipment as per the code of life saving appliances. The boat is to be loaded uniformly with sand bags each of 50 kg to make up the full compliment of persons it can carry at the rate of 75 kg per person together with excess of 50% of the total weight of the loaded boat.

Precautions to be observed:

The loading of the sand bags to be done after the boat is taken off its cradle and is in the launching position.

The test is to be done only if the boat is plumbing on the water side . In anchorage it can be done for all the boats. When alongside a jetty it can be done on the boat on the water side.

The load is kept for 30 minutes and after completion of the test and the weights removed, the davits to be checked for any permanent deformation.

Dynamic test:- The boat is to be loaded with sand bags representing the full complement of persons as stated above together with 10% excess load of the total loaded boat.

The same precautions to be observed as stated above.

From its launching position , the hand brake is lifted till the boat descends at constant speed of 0.6 meters per second, when the hand brake is released. The descent of the boat must be arrested instantaneously without any jerk to the davits and supports.

MUMBAI CENTRE

APRIL 2016 Mr Pakrasi

(51)State the type of ship you have sailed and the type of cargos carried on that ship.

Answer:-The candidates must be prepared with the following information:

* Name of last ship sailed:

* main dimensions ( L,B and D):

* Dead Weight in tonnes:

* Number of holds if bulk carrier:

* number and arrangement of cargo tanks if tanker:

* Number of TEUs carrying capacity if container ship.:

Candidates must know the types of cargos carried . If not known they should find out.

Note: cargos have their own properties which affect safety and stability. The candidates must find out about these peculiarities as they can be cross questioned on these aspects.

Specialities of each type of vessel should be learnt . For example speciality of container ships is the torsion box , passage to the forecastle and bunkering arrangement.

In tankers the sp;eciality would be inert gas arrangement, P/V valves, deck seal , COW procedure, flammability and safe entry procedures in tanks.

Candidates who have worked on LPG or LNG ships will be grilled on all operational requirements of these ships and so a revision of the LPG and /or LNG specialisation courses would be advised.

52)Who is the contracting party for India? Who controls and implements them in India and how? Who is the Administration?

Answer: - In India the contracting party is the Director general of shipping, D.G Mumbai.

The implementation is done by the surveyors working in the various districts under the principal officers and the surveyors working in the DG of Shipping under the chief surveyor and the nautical advisor .

Administration means Government of India and particularly the Ministry of Transport and Shipping. (53) What is ISM? What is the need of ISM? To which types of ships it applies? What are the requirements and objectives of ISM? In India who controls ISM? Name the certificate issued under ISM.? What is DOC and to whom is it issued?

Answer:- ISM is International Safety Management of ships. It is a safety and pollution prevention code prescribed for committed following by all ships belonging to all the flags of the world and who are signatories to this code. It applies to all ships proceeding to sea, except naval ships.

Its need is necessitated by the requirement of safe operation of ships all over the world so that loss of life and pollution prevention of the sea and the atmosphere are attained and cargos are delivered without contamination and loss.

The objectives broadly stated are: *Safety at sea

Prevention of human injury or loss of life

Prevention of damage to environment or pollution of environment

Preparing the ships personnel for emergencies,

The personnel involved have declared responsibilities which are documented and observed in their day to day work and finally audited at regular intervals by the administration and /or classification societies

One worthy feature of this code is the recording of near misses and accidents on the ship and analysing their causes to prevent future recurrence of similar situations.

In India ISM is controlled by the DG of shipping Mumbai.

The certificate issued to the ship is called SMC, Safety Management Certificate. The company managing the ship is given a DOC, a Document of Compliance. Both these certificates are valid for five years and are harmonised with other statutory certificates. The certificates are issued after an audit conducted on the ship and the operational shore office by the surveyors of the DG of shipping or the surveyors of the Classification societies approved by the DG of Shipping. (54) What is ISPS? Why do we need ISPS? Who controls ISPS and how?.If your ship is in port having a higher security level than your ship, How will you change your ships security level . Explain the procedure

Answer:- ISPS is International ship and Port security code.

We need ISPS to secure our ships from the danger of terrorist threats .

ISPS is controlled by the port organizations through the port security officer, on the ships by the ships security officer or the Master, and in the owners office by the company security officer. The declaration of security level is conveyed by the contracting government security officer after ascertaining that a grave threat is imminent in the cioncerned port and ships within it.

If the ship is in the port having a higher security level than the ship, the ships security officer or the Master of the ship will give a written declaration that the security level has been raised. This declaration will be conveyed to the port security officer, the crew and officers on board and the company security officer. This declaration will also be logged in the ships official log book. This is in accordance to regulation 5.2 of the ISPS code.

(55) When your ship has left the port and goes along side another ship for cargo transfer, how will you maintain the security level of your ship. Explain the procedure.

Answer:- As per regulation 5.2 of the ISPS code, the Master or the ships security officer can issue a declaration to the crew and officers on board that the security level has been lowered to the level maintained by the other ship. This declaration will be conveyed to the company security officer as well as a log entry will be made in the official log book of the ship accordingly.

(56) What is a fair lead. Where is it commonly used.

Answer:- A fairlead is a set of pulleys or rollers which guide the mooring rope or wire according to the required direction, so that unnecessary friction or chaffing is avoided. Fairleads are commonly used on the deck to guide mooring ropes and back spring wires for mooring the ship.

(57) Define tensile strength, How is it measured ? Describe the test procedure. From the test results how do you assess the strength of the material.

Answer:- The tensile strength of a component is the safe tension across its cross section , it can withstand without any deformation of shape or dimensions when the tension is removed.

The tensile strength of a material is measured by making a standard test piece of the material and subjecting the test piece to a variable tensile load which can be gradually increased upto the elastic limit. The tensile force noted in Newtons divided by the cross section of the test piece in mm2 is the tensile strength of the material given in Newtons / mm2

If the tension is increased further the material yields and elongation is set in . Further increase of the tension leads to the breaking of the test piece . The tension in Newtons when break has occurred divided by the original cross section is the ultimate tensile strength of the material.

An important property of ductility is given by proceeding the test to the ultimate tensile strength . During the yield stage the test piece has elongated and this elongated length can be found by fitting the two pieces along the break contour and measuring the length between the pop marks. The increase in length found from the difference between the new length and the original length divided by the original length gives the percentage elongation which signifies the materials ductility. In ship building , for fabrication of steel plates ductility is very important as it allows steel plates to be shaped in cold condition without affecting the grain structure or metallurgy. Generally speaking ductility is directly proportional to the percentage elongation of a metal.

58) What is surface hardness? How is it tested and how is it measured?

Answer:- The hardness of a material determines basically its resistance to wear. . Surface hardness of the metal is the ability of the metal to prevent wear by abrasion when two components in contact are subjected to relative motion.

7

BRINELL HARDNESS TESTING MACHINE

Brinell tes :-: This test consists of indenting the surface of a metal

by means of a 10 mm diameter hardened steel ball under load. The

Brinell number is a function of the load applied and the area of

indentation,

Brinell number = Load in Newtons divided by area of indentation in mm2

(59) What is notch test? Why is this test performed .Describe the procedure for the test and its measure.

Answer:- This test also called impact test is useful !'or determining differences in materials due to heat treatment, working and casting, that would not be otherwise indicated hy the tensile test. It does not give accurately a measure of a matcrials\ resistance to impact.

A notched test piece is gripped in a vice and is fractured by means of' a swinging hammer . After the specimen is

fractured the hammer arm engages with a pointer which is carried

for the remainder of the swing of the arm. At the completion of the

hammer\ swing the pointer is disengaged and the reading

indicated by the pointer is the energy given up by the hammer in

fracturing the specimen. Usually three such tests are carried out

upon the same specimen and the average energy to fracture is the

impact value.

By notching the specimen the impact value is to some extent a

measure of the material's notch brittleness or ability to retard crack propagation. From the practical standpoint this may be

clarified to some extent: Where changes of section occur in loaded

materials (e.g. shafts, bolts, etc.) stress concentration occurs and

the foregoing test measures the materials resistance to failure at

these discontinuities.

MAY 2016 Mr Pakrasi

(60) Explain the inputs in the attachments A and B of the IOPP certificate.

Answer:- In general terms the inputs of the attachments form A and form B are as follows

* Form A is for other ships and Form B is for tankers..

FORM A:- * all identification particulars of the ship including any major conversions.

* Approval details of the bilge separation equipment.

* Approval details of the oil in water monitoring equipment.

* Maximum through put of the system in M3 /hr.

* locations and total volume of bilge wells in machinery space.

* Locations and and total volume of all sludge tanks in the machinery space.

* Details of approved incinerator capable of burning sludge.

* Evidence of approved SOPEP properly updated.

FORM B:- * all identification particulars of the ship including any major conversions.

All machinery space equipment same details as per FORM A.

Ship type crude oil or product carrier. Or combination carrier.

* Whether the ship has segregated ballast tanks (new system) or designated ballast tanks (old system).

* Details of locations of ballast tanks , total volume in cubic meters and type whether segregated, CBT or Double hulled.

*Details of slop tanks location and capacity in cubic meters.

* Details and approval of the COW equipment

* Details of the ODM approval, type and test.

(61) When did the ISM code come into force and when did it become effective on ships.

Answer:- From the year 1994, it has been a very vital component of the SOLAS convention (safety of life at sea). it was in this year that this code was formally adopted and integrated as a part of thesolas convention.

From july 1998 it became mandatory on all ships.

(62) Explain ISPS and DOS

Answer:- ISPS is International ship and port Security code , which describes a mandatory system to be followed by all ships in maintaining security and awareness against any security threat from terrorist attack . The code explains the three levels of security to be maintained as per the intensity of the threat. The ship must have a documented security plan maintained and operated by the ship security officer or the Master of the ship.

DOS is Declaration of security. This declaration relates to the security level and is issued by the security officer or Master of the ship based on the authentic information received by him either from the port authority or the contracting government. (63) Sketch the anchor chain bitter end connection in the ship.

Answer:- The sketch of the chain connection to the collision bulkhead stiffener frames is given in sketch. The chain connects to a shackle of 50% strength of the chain link so that it can be released by breaking in an emergency if the locking pin cannot be dismantled.

(64) Explain the anchor stowage on the ship with a suitable sketch.

Answer:-

The anchor is stowed in a pipe attached to the Bow side and the forecastle deck plating called the Hawse pipe . Both at the deck plate and at the bow plating , the hawse pipe connects the plating by a welded cast steel fring . This ring at both ends prevents the chain or the anchor from rubbing on the hawse pipe , thereby preventing damage by wear and abrasion of the hawse pipe. During dry docking the rings are to be built up by welding at the positions of maximum wear, where the chain has grooved the ring.

(65) What is torsion box . In which type of ship it is fitted and where is it fitted and why it is fitted.

Answer:- Torsion boxes are fitted on the main deck structure of the container ships. Because of the wide hatches the deck plating must be thick, and higher tensile steel is often used. The deck , side shell and longitudinal bulkheads are longitudinally framed in addition to the double bottom. The hatch coamings may be continuous and therefore improve the longitudinal strength. Problems may arise in these vessels due to the lack of torsional strength caused by the large hatches. The problem is overcome to some extent by fitting torsion boxes on each side of the ship. These boxes are formed by the upper deck, top part of the longitudinal bulkhead, sheer strake and upper platform, all of which are of thick material . The boxes are supported inside by transverses and wash bulkheads in addition to the longitudinal framing.

These boxes are only effective if they are effectively tied at their ends. At the after end they extend into the engine room and are tied to deep transverse webs. Similarly at the fore end, they are carried as far forward as the form of the ship will allow and are welded to transverse webs. The longitudinal bulkheads below the box may have to be stepped in board to suit the shape of the ship, the main longitudinal bulkhead being scarphed into the stepped section.

(66) What is the purpose of the duct keel ? In which type of ships it is fitted.

Answer:- The duct keel is a space provided mainly in Bulk carriers , container ships and car carriers. It is the space above the keel plate and below the inner bottom plating and bounded on the sides by two water tight intercostals extending from the engine room forward bulkhead to the collision bulkhead.

The entrance from the Engine room is through a proper manhole door and on the other end , there is a vertical passage leading to the main deck just aft of the collision bulkhead and access provided by either a hatch opening fitted with a door or a flush manhole door.

The duct keel is mainly used for conveying all the hold bilge pipes as well as the ballast pipes. The individual ballast tank valves are situated in the duct keel and they are shut and opened hydraulically from a control console in the engine room.

Some large ductkeels are provided with a push trolley running on wheels on rails.to convey tools and spares for repair work on the valves and pipes.

(67) What is EEDI and SEEMP. How is CO2 emmissions reduced

Answer:- EEDI is energy efficiency design index It is calculated for each new engine fitted to the ship after a prescribed test bed trial. IT is also calculated to engines undergone special conversions for NOX emission as per annex 6.

SEEMP is ship energy efficiency maintenance plan, which is required to be kept by each ship . This plan is developed from the guidelines adopted by IMO and becomes part of the ships SMS

CO2 emissions are reduced by burning efficiently distillate fuels with lower sulphur content which is gradually being introduced by IMO through the time bound tier system. By 2020 the sulphur content of distillate fuels will be 0.1 %.

(68) From which date ISM has come into force. Is it mentioned in SOLAS, if so in which chapter. Explain DOC ,SMC and SMS. If a company has ships of different flags under its management, can it have the same DOC?

Answer:- ISM was introduced in the year 1994 and it has become mandatory since July 1998. DOC is document of compliance and is issued to the shore office controlling and managing the operations of the ship. SMC is safety management certificate issued to the ship after satisfactorily undergoing a statutory audit by the Administration or the Classification society authorised to carry out the audit. SMS is the safety management system . It is the documented representation consisting of the various ship board manuals forming the system. The issue of a DOC to the company is enough to manage a ship of any flag since the DOC IS ISSUED TO THE COMPANY. The only requirement is that each ship under the company management must have a certified true copy of the valid DOC on board at the time of the statutory audit.

(69) Sketch the duct keel with dimensions. What is the purpose of the duct keel?

Answer:- The duct keel is a passage extending from the E.R.forward bulkhead to the collision bulkhead. It is meant for conveying the hold bilge pipes and the ballast pipes of the ship, especially bulk carriers, container ships and car carriers.

(70) Explain the contents (chapters) of SOLAS. What are the new chapters of SOLAS.

Answer:- SOLAS has 12 chapters . the chapters cover the following topics or sections.

One---------------General provisions.

TWO------------- structural construction details ,subdivision, stability , machinery and electrical installation, fire protection, detection and extinction.

THREE-----------Life saving appliances and arrangement.

FOUR--------- Radio communications (GMDSS)

FIVE----------- Safety of Navigation (ROR )

SIX-------------Carriage of cargoes( properties of cargoes requiring attention for safety and stability)

SEVEN_______ Carriage of dangerous Goods.

EIGHT-------------Nuclear ships

NINE--------- Management for the safe operation of ships

(ISM code)

TEN----------- Safety measures for high speed craft.

ELEVEN------Special measures to enhance Maritime safety and security ( port state control, enhanced surveys and ship security)

TWELVE------Additional requirements for bulk carriers.

The new chapters are nine, ten , eleven and twelve.

(71) What is Polar code. Broadly state its regulations. How is it linked to MARPOL and SOLAS.

Answer:- The International Code for Ships Operating in Polar Waters has been developed to supplement existing IMO instruments in order to increase the safety of ships' operation and mitigate the impact on the people and environment in the remote, vulnerable and potentially harsh polar waters.

2 The Code acknowledges that polar water operation may impose additional demands on ships, their systems and operation beyond the existing requirements of the International Convention for the Safety of Life at Sea (SOLAS), 1974, the International Convention for the Prevention of Pollution from Ships, 1973, as modified by the Protocol of 1978 relating thereto as amended by the 1997 Protocol, and other relevant binding IMO instruments.

The goal of this Code is to provide for safe ship operation and the protection of the polar environment by addressing risks present in polar waters and not adequately mitigated by other instruments of the Organization

Its regulations covers the following requirements of ship operation in the polar regions both ARCTIC and ANTARCTIC.:

The code covers the solas regulations through the first 12 chapters relating to SOLAS, and the second group of chapters from 1 to 5 covering the MARPOL requirements. Annex 6 which refers to Air Pollution is aleready covered in the MARPOL regulations annex 6.

SOLAS

CHAPTER 1--- GENERA;L

CHAPTER 2 POLAR WATER OPERATIONAL MANUAL (PWOM) .

CHAPTER 3 SHIP STRUCTURE

CHAPTER 4 SUBDIVISION AND STABILIT

CHAPTER 5 WATERTIGHT AND WEATHERTIGHT INTEGRITY

CHAPTER 6 MACHINERY INSTALLATIONS

CHAPTER 7 FIRE SAFETY/PROTECTION

CHAPTER 8 LIFE-SAVING APPLIANCES AND ARRANGEMENTS

CHAPTER 9 SAFETY OF NAVIGATION

CHAPTER 10 COMMUNICATION

CHAPTER 11 VOYAGE PLANNING

CHAPTER 12 MANNING AND TRAINING

POLLUTION PREVENTION MEASURES .. MARPOL

CHAPTER 1 PREVENTION OF POLLUTION BY OIL

CHAPTER 2 CONTROL OF POLLUTION BY NOXIOUS LIQUID SUBSTANCES IN BULK

CHAPTER 3 PREVENTION OF POLLUTION BY HARMFUL SUBSTANCES CARRIED BY SEA IN PACKAGED FORM

CHAPTER 4 PREVENTION OF POLLUTION BY SEWAGE FROM SHIPS

CHAPTER 5 .. PREVENTION OF POLLUTION BY GARBAGE FROM SHIPS

(72) What is the role of the classification society.

Answer:-A classification society is a standards organization which mainly caters to design requirements for reliability of ships machinery and hull. Initially the classification societies were patronized by the insurance companies for back up assurance that the ships insured by the insurance companies are safe.

Since the classification societies are learned bodies having a vast bank of information on ships reliability and safety, the administrations as well as IMO take their assistance in their various executive functions and hence now the classification societies have become the executive arm of the Administration. Flag states like Panama and Liberia as well as Bermuda use the services of the classification societies for all their Technical functions.

(73) What is condition of class.

(a) Answer:- A condition of class is a deficiency noted by the surveyor on a machinery component or structural member during the course of a survey. The deficiency may have been temporarily dealt with by a suitable patch work repair for a limited period say 3 months or 6 months, when it will be reviewed if permanent repairs are not carried out in this time.

It is to be noted that during special surveys all C.O.Cs should be suitably dealt with so no C.O.Cs exist.

(74) What is the difference between statutory certificates and class certificates.

Answer:-Statutory certificates means the certificates which by law is required to be carried by the ship in accordance to the various regulations under the various conventions of IMO for which the administration is a signatory. All statutory certificates are issued by the Administration or on behalf of the Administration by recognized bodies

Clasification societies issue their certificates and reports pertaining to the ships machinery and Hull and these certificates are issued mainly for reliability. Based on these certificates, the ship is issued the Cargo ship safety construction certificate which happens to be the link between statutory and class certificates.(75)What types of steel are used in ship construction. Where is HTS used and why.

Answer:- There are four grades of steel in common use, Specified by the classification societies as grades A, B, D, and E depending largely upon their degree of notch toughness. Grade A has the least resistance to brittle Fracture whilst grade E is termed extra notch tough . Grade D has sufficient resistances to cracks for it to be used extensively for main structural material.

The disposition of the grade in any ship depends upon the thickness of the material , the part of the ship under consideration and the stress to which it may be subject . For instance, the bottom shell plating of a ship within the midship portion of the ship will have the following grade requirements.

Plate thickness Grade of steel

Up to 20.5 mm A

20.5to25.5 mm B

25.5mm to 40 mm D

Above 40 mm E

The tensile strength of the different grade remains constant at between 400MN/m2. The difference ;lies in the chemical composition which improve the impact strength of D and E steels. Impact resistances is measured by mean of a charpy test in which specimens may be tested at a variety of temperature. The following table shows the minimum value required by Lloyds register.

Type of steel Temperature Impact resistance