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SOUTH TYNESIDE COLLEGEFACULTY OF MARINE AND MECHANICAL ENGII\EERING

CLASS 4 EXAMINATION OUESTIONS

Explain what you know about 66M" Notices.Merchant shipping notices, or "M" notices as they are commonly called, occupy a special position.are advisory notices which do not have a force in law, but those which give advice on safety matterregarded as authoritative documents by course of inquiry into shipping casualties and as such woulrconsidered extremely persuasive in a legal sense.There are now three tlpes of notice issued by the MCA

1. MGN ( Marine Guidance Notes ) - BlueProvide advice and guidance on safety and pollution matters.

2. MIN ( Marine Information Notices ) - GreenProvide information intended for a more limited audience or of short term duration.

3. MSN ( Marine Shipping Notice ) - WhiteWill contain mandatory information relating to the legal requirement set out in related statutoryinstruments.

There is no legal requirements to carry Marine Guidance Notes and Marine information Notes onUK registered vessels.It is a legal requirement to carry Merchant Shipping Notices.

Explain what you know about " Code of Safe Working Practices".Accidents are usually the result of carelessness, mistakes, lack of thought or care and often result in

Consideration must be given on how to avoid accidents hence the " Code of Safe Working practiceExamples include the wearing of working clothes chosen forthe job with its hazards in mind. Theyfit fairly closely with no loose flaps, straps or ragged pockets. Ciothing should cover as much as theas possible and a stout pair of shoes should be worn, with steel toecaps. Neck chains, finger rings arwristwatches should not be worn, particularly in the vicinity of rotating machinery. Where particulahazards are present appropriate protection such as goggles or ear muffi, should be worn.

When overhauling machinery or equipment it must be effectively isolated from all sources of powermay involve unplugging from an electrical circuit, the removal of fuses or the securing open of circubreakers. . Suction and discharge valves of pumps should be securely closed and the pump casing relpressure. Special care should be taken with steam operated or steam using equipmetrt to "ngye no Fbuild up occurs.

When lifting components during overhaul, screw in eyebolts should be used where possible. These :be fully entered up to the collar and the thread of the eyebolt should be in good condition. Lifting wshould be in good condition without broken strands or sharp edges.

Before any work is done on the main engine, the turning gear should be engaged and a warning noticposted at the control position. Lubricating oil in the working area should be cleaned up and wherenecessary suitable staging erected. The turning gear should be made inoperative if nofrequired duriroverhaul- Where it is used, care must be taken to ensure all personnel are clear before it is used.

Overhead working, boiler operation. Entry into enclosed spaces are other examples where special carprocedures have to be rigidly followed never taking short cuts.

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3' What portable extinguishers would you expect to find in an engine room and what coloused?

The outer container contains sodium bicarbonate powder. A capsule of carbon dioxide gas is locatrbeneath a plunger mechanism in the central cap. bn depressing the plunger the carbon dioxide gasthe powder up a discharge tube and out if the discharg e-nozzle.The dry powder extinguisher con be used on all classes offire but it has no cooling effecl It is t,located near electrical equipment in the mochinery tpori and elsewhere on the ship.

Foam - Red 5% Cream/Buff-- ChemicalThe main container is filled with sodium bicarbonate solution and a long inner polyhene containerwith aluminium sulphate. The inner container is sealed by a cap held in place Uy r plunger. Whenplunger is unlocked by turning it , the cap is released. The extinguisher is then inverted-for the twoto mix- Carbon dioxide is produced by the reaction which pressurises the container and forces out tfoam.

Foam - Red 5% Cream/Buff-- MechanicalThe outer container in this case is filled with water. The central container holds a carbon dioxide cha foam solution. A plunger mechanism with a safety guard is located above the central container.When the plunger is depressed the carbon dioxide is released and the foam solution and the water n:are then forced out through a special nozzle which creates the mechanical foam. This extinguisher Iinternal pipe and is operated in the upright position.Foam extinguishers are used on class B fires and witl be located in the vicinity ofjtammabte tiqa

C.O2 - Red 5% BlackA very strong container is used to store liquid carbon dioxide under pressure. A central tube providrouter passage for the carbon dioxide which is released either by a plunger bursting a disc or a valveoperated by a trigger. The liquid changes to a gas as it leaves the ixtinguisher *d purses through thswivel pipe or hose to a discharge horn.Carbon dioxide extinguishers are mainty used on Class B and Cfires and wig befound in the maspace, particularly near electrical equipmenl The carbon dioxitle extinguisher i not permitted itaccommodation since, in a conJined space it is lethal.

CFC Extinguishers - Red 5%Green

Soda - Acid RedThe container of this extinguisher holds a sodium bicarbonate solution. The screw-on cap contains rplunger mechanism covered by a safety guard. Below the plunger is a glass phial containing sulphurWhen the plunger is struck the glass phial is broken and the acid and sodium bicarbonate mix. Theresulting chemical reaction produces carbon dioxide gas which pressurises the space above the liquirforcing it out through the internal pipe to the nozzle.This extinguisher is usedfor class Afires and will befound in the accommodation ereas.

what type of fire extinguisher would be used on a fire in:-?(a) Galley (b) Accommodation (c) Control Room or Radio Room (d) Electrical Switchboard(e) Pump Room

(a) Galley - CO2 and Dry Powder(b) Accommodation - Soda Acid Extinguisher ( see below for description )(c) control Room or Radio Room - coz or Dry powder(d) Electrical Switchboard - COZ or Dry powder(e) Pumproom - Foam, COz or Dry powder

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5. what are the main causes of serious engine room fires ?oil leaks. Fuel, hydraulic or lubricating oil onto hot surfaces.Smoking, burning or welding.Rags and combustible debris allowed to build up in the bilge's

\ilhat immediate action must be taken if a fire becomes serious enough to have to evacuate allpersonnel from the engine room and what precautions must be taken before re-entering?Flood the machinery space with whatever fixed fire installation is fitted. Say CO2.Before flooding get everybody out. - do a head count.Where possible all personnel must be made aware of the decision to flood the machinery space withThe space must then be completely sealed 4gainst the entry and exit of air and all oil suiplies isolatrtank valves.When all these matters have been attended too the COz can be admitted and if the srurounding bulklhold to contain the ftre , it will quickly go out. Cooling of the boundary bulkheads should continueoutside the space while flooding is taking place. When the extinguished fir. has been left long enoucool down the space can be re-entered. This should be done from the tunnel, if there is one, oi fro-lowest point from the seat of the fire. Engineers wearing breathing apparatus may now enter, takiwater spray hoses with them to cool down any hot surfaces. Coolingand smoke dispersal are the firpriorities, to provide an atmosphere in which others can operate andgradually bringthe machinery sback into service.Where a machinery space fire involves electrical equipment then only dry powder or Co2extinguislbe used until the equipment is isolated.

What pumps on board ship can be used to supply water to the fire main ?Fire pump.- usually two or three fittedFire and bilge pump.General service pump.Emergency fire pump.

Is there an emergency fire pump ? If the answer is y€s, where is it fitted and how is it tested?External to the machinery space.- Run on a weekly basis.Some pumps may be fitted in the steering compartrnent.

Define what you would consider to be an enclosed space where the internal atmosphere may brfrequently hazardous to personnel who may enter.Duct Keel, double bottom tanks, cofferdams, boilers, CO2 rooms, pumprooms. Bow thrustercompartments should be teated with caution if ventilation fans have not been running. Fore peak anrpeak tanks should also be well ventilated and tested before entry.

Describe the procedure which should be adopted:-(a) Before anyone is allowed to enter an enclosed space.(b) While anyone is working inside a closed space.(i) Ventilation for at least 24 fus.(ii) Test of atrnosphere by a chemist or Chief Officer for Oxygen and Hydrocarbon content. Zlyo o>(iii) Tank entry permit and tally board for personnel to enter tank.(iv) Breathing apparatus at tank entrance, lifeline and portable lights(air), communication, ild tallier

people entering along with ELSA sets.

(b) While anyone is working in the tank there must be a man at the entrance at all times with a mezucommunication between him and the person(s) in the tank and the Bridge.

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what types of pumps are suitable for use as bilge pumps?Positive displacement. - small volumes for use wifi owscentrifugal with priming pump - Large volume discharge.

Give reasons why a bilge pump may not be able to remove water from bilges.state typical suction and delivery pressures.Blocked strum box. ( very high nuru.r* on the gauge)Hole in suction line. ( zero or very low vacuum on the gauge )Priming pump not functioning if working in series with centrifugal pump.

Explain what is the emergency bilge suction ( injection). Why is it necessarT and how is it bninto operation?A bilge injection valve is fitted to the end of a branch line connecting with the main sea water suctThe bilge injection valve is always of the screw down non-return type. This valve enables the largseawater cooling pump to be used as a bilge pump in an emergency. To bring the bilge injection vuse during an emergency , the bilge injection valve is openea rutyand the sea suctioi valve is full;After it is established that the sea watir pump is capable of lowering the water level in the enginesea water suction may be opened slowly. This should be done in stales so that the tank tops are nodry,as this would cause the sea water pump to lose suction. Care should be taken to ensue that theoften situated on the outlet from the main condenser does not discharge near any electrical equipmrNB. Sea water pumps are not usually self priming, if of the centrifugiltype.

lhat is the purpose of the oily water separator?To allow the bilges to pumped overboard with an oil content of not more than l5ppm.Read MARPOL regulations.

Explain in detait the procedure for testing the steering gear before leaving port.check for oil leaks and any loose linkages on th. steering gear.check for correct oil level and test low level alarm.Run one unit at a time, 30 degs- to 35 degs. in 28 secs at full power. where only one main unit is fianx' unit, the auxiliaty unit must go from 20 degs. to 20 degs. In 60 secs. at g knots or half speed.Test the communication link between the Bridge and the Stee.irrg compartment.

What is the duty of the engine room crane?To enable large and hearry engine components to be manoeuwed around the Engine room in a safemanner.

Detail checks which should be carried out before using the crane and possible hazards if notfunctioning correctly.Check SWL is not exceeded.Check that the direction indicators on the controls correspond to the actual movement of the crane.Check that the limit switches are working.

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Check that the brake is operational.Check that all personnel involved understand the signals to be used in any repair or overhaul.

Give the correct procedure for starting an air compressor.(a) Check the oil level(b) Check the cooling water.(c) Ensure that the interstage drains are open.(d) Check that all the correct valves *" ol"n fully to the air receiver and that there is sufficient ca1available in the air receiver..(e) If a manual unloader is fitted ensure that it is open. ( machine must be started in the unloadedposition).(D When the machine is up to speed, close the unloader and the interstage drains.

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19. What is the purpose of fitting a bursting disc into the air compressor casing?A bursting disc' or sometimes a water jacket relief valve are fittedto prevent a build-up of pressur€a cooler tube fail allo*ing high pressure air to enter the cooling *ut.i space.

Describe the procedure required to connect in parallel one diesel or steam driven alternatoralready on the switchboard with another alternator.Three-phase alternators ilranged for parallel operation require a considerable amount of instrumeThis will include arnmeters, wattmeter, voltmeter, frequency meter and a synchronising device. Mthese instruments will use transformers to reduce the actual values taken to the instrument. This alenables switching, for instance, between phases or an incoming machine and the bus-bar, so that o:instnrment can display one of a number of values. The watfineter measures the power being used ircircuit' which' because of the power factor aspect of alternating current load. will be less thL the p:the volts and amps.Reverse power protection is provided to alternators since reverse current protection cannot be used.Alternatively various trips may be provided in the event of the prime mover failure to ensure that thalternator does not act as a motor.The operation of paralleling two alternators requires the voltage to be equal and in phase. The altercurrent output of any machine is always changing, so for two machines to operate together their volmust be changing at the same rate or frequency and be reaching their ma,rimum ( or Ly other valuetogetherThey are then said to be' in phase'. Use is nowadays made of a synchroscope when paralleling twomachines. The synchroscope has two windings which are connected one to each side of th. p*utt"lswitch.A pointer is free to rotate and is moved by the magnetic effect of the two windings. When the two vsupplies are in phase the pointer is stationary in the 12 o'clock position. If the pJinter is rotating thtfrequency difference exists and the dial is marked for clockwise rotation FAST and anti-clockwise rsl-ow, the reference being to the incoming machine frequency.To parallel an incoming machine to a running machine therefore, it is necessary to ensure firstly thavoltages are equal. Voltmeters are provided for this purpose. Secondly the frequencies must UL Urointo phase. In practice the synchroscope usually *orr.r slowty in the fast direction and the parallelirswitch is closed as the pointer reaches the l1 o'clock position. This results in the incoming machinrimmediately accepting a small amount of load.A set of three lamps may also be provided to enable synchronising. The sequence method of lampconnection has a key latnp connected across one phase with the two other lamps connected over thetwo phases. If the frequencies of the machines are different. The lamps will brighten and darken inrotation, depending upon the incoming frequency being FAST or SLOW. The correct moment forsynchronising is when the key larnp is dark and the other two are equally bright.

What is the purpose of having a synchroscope and why must it not be allowed to run continuoTo ensure alternators to be connected to bus-bars are at th; correct frequency.Not to be allowed to rtrrt continuously because they are not continuousiy rated and will burn out.

Explain how an emergency alternator starts and supplies power in the event of a blackout.(a) Double pole switch trips on lose of power and on tripping makes contact with emergency switch

supplying power to emergency generator starter motor.(b) A low voltage coil, typically 24v, is connected to the main switchboard. This coil is normally

energised and corutected to a normally open contactor on the air start system for the alternator. rthe main power fails the coil de-energises, thus completing the air start system and starting thealternator.once the alternator has started the air will shut off.When the machine is up to speed and has the correct cycles and volts, the auto synchroniser willthe breaker and put it on the board, (emergency board) to supply the essential services.

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How can a blackout be simulated to test the operation of the emergency alternator?Turn auto synch to offposition to prevent the emergency generator tying to put itself on the boardstarts. Shut power offto starting coil, this will de-energise coil and machine will start.

How often should an electric motor be cleaned?Unless there are any specific problems every 5 years. Use of vibration monitors are helpful in highbearing problems and thermal trips in the windings can give prior warning of impending problems.

How would you overhaul an electric motor that has been flooded with sea water?Strip down and wash with distilled water, then dry out, if possible in an oven, then check meggar rShould be minimum of I megohm. Heating lamps can also be used. On completion coat with ,. gorquality electrical varnish.

Explain how to check the insulation resistance of the motor using a ..Meggerrr.Corurect the Meggar between each phase in nrrn and the motor casing, after good contact has been :removing paint etc. Resistance should be I megohm.

Outline the dangers to pensonnel who may have to enter a battery room to check the conditio:batteries on charge.Hydrogen fumes in poorly ventilated battery rooms which contain lead-acid batteries can be fatal. lrnaked flames and danger from sulphuric acid burns. Safety gear must be worn including full face v

No smoking as there could be danger of explosion.

What is the temperature inside low pressure evaporators and why is the water produced suitrdrinking?Drinking water can only be made from salt water in evaporators if it is boiled above 75 degs. C. Mrthe low pressure plants operate at temps ranging from 4d degs C. to 60 degs C. and are therefore urfor making drinking water.Other problems to look out for are additives used in diesel engine cooling systems and inhibitors u'water systems to prevent fouling by marine growth.The evaporator should not be used within 12 mi.land

what are the reasons for using the main engine turning gear?(a) To ensure that the engine is warmed up evinly dissipalittg *y thermal stresses in materials ever

therefore the engine can be loaded more quickty.(b) For warming through with the indicator cocks open to ensure there is no water leakage in the cy(c) To be engaged if any major overhaul of the engine is taking place.(d) For taking deflections.

Why is tappet clearance necessary and what effect would insufficient or excessive clearance h:engine operation?Tappet clearances are necessary to allow for the thermal expansion of the valve spindle length at wotemperatures' and to ensure that positive closing of the valve continues as it wears or seats d*irrg ,r,Clearances should normally be set while the engine is cold and the czrm follower is offthe cam peakwear of the valve gear will tend to increase clearances.Excessive tappet clearances will cause the valve to open late and close early in the cycle and will recma'ximum lift- It will also cause noise, and eventually damage, from the impact of working surfacesInsufficient clearance will cause the valve to open early and close late with increased marimum lift.extreme cases' it may prevent the valve from closing completely as it expands or beds in. This in tulcause hot gases to blow past valve faces, causing .ruln burning and low compression.

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Describe how to prepare the main engine from cold to ready to start to manoeuvring includi:that require to be carried out.(1) Before a large diesel engine is started it must be warmed through bv circulating hot water throrjackets etc' This will enable the various engine parts to expand in relation to one another and aengine load to be increased sooner rather than later.

The lubricating oil should also be heated and circulated around the bearings etc., and the pisto:cooled.The various return pipes on both the water and oil systems should be checked to ensure no bloand the return temperatues should be monitored.

(2) The various supply tanks, filters, valves and drains are all to be checked and opened or closed irequired

(3) All control equipment, alarms etc. should be examined for correct operation.(4) The indicator cocks should be open and the turning gear engaged and started to ensure that ther

water present in the cylinders. If any water issues furth.r investigation can be ca:ried out to asc, lTne cause.(5) All oil levels should be checked, i.e. sump, turbochargers, governors etc.(6) The fuel oil system can be lined up and circulated with hot fuel.(7) Any scavenge blowers if manually operated, should be started.(8) Manually operate the cylinder lubri.utorr.(9) The turning gear should be removed and the engine blown over on air before closing the indica

cocks.(10) The engine is now available for stand by.

Why should the cylinder indicator cocks be left open until the engine has first been turned ov,starting air?To ensure that no water issues from the cocks which would indicate a leak from the liner, cylinderhead, piston cooling, turbo brower or injector cooling.

Describe the routine inspection you would carry out before taking over the watch on a manneengine room arrangement..Check the firnnel emissions. White smoke, black smoke, steam or sparks.Check steering gear and fridge flats.Enter the engine room from the top. Do not use the lift.Check cooling water header tank.check main engine cooling water returns and temperatures.check piston cooling water returns and temperatures.Listen for any unusual noises.Check turbo charger oil levelsCheck observation tank for signs of oil.Check mist detector.Check condition of bilges.Check purifier flat and condition of the fuel oil tanks. i.e. full, empty, temperature. Drain of water.Enter control .oop: check log book and note any irregularities.Confirm the condition of the electrical supply equipmint. How many alternators on load, amount ofon the board. Earth faults. Stand by machines.

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Read any curent standing orders.The duty engineer should then

1nfo* the engineer taking over the watch of any abnormal operatingconditions which have occured during the watch. Any oidrr, from the Bridge, recorded in the log brshould be pointed out. Any repairs should be reported together with information on any machinery ttbeen dismantled' The presence of any other members oflhip's staff in the engine room e. g. Dayvorshould be reported.

34. Give the various operating pressures and temperatures of an engine you are familiar wiScavenge air temperature - 40/45 degs. C F.O. Pressure - 5/6 BarScavenge air pressureL.O. pressureL.O. temperafireJacket C.W. pressure

- 1.0 Bar- 2.0 Bar- 45 degs. C- 3.0 Bar

F.O. Temperahre - 125 Degs. CCylinder oil pressure - 40 bar

Jacket C.W. temperatue - 65 degs. C

What factors must be present for an explosion to occur in the diesel engine crankcase?For a crankcase explosion to occur, oil mist must be present in the crankcase, and a hot spot mustdevelop, perhaps from bearing wear or stuffing box rub etc. The hot spot then ignites the oil mist caan explosion. ( See handout on crankcase explosions or Note 22 CLass 4 )

What device may be used to detect and warn of dangerous conditions within the crankcase?A Graviner oil mist detector is used to detect and warn of dangerous levels of oil mist in the crankcaThe detector consists of two tubes, fitted at one end of each is a photo electric cell, the other end is alens to allow the passage of light through the tube of the P.E. cell. Light comes from a single bulb areflected to each tube by a mirror. One tube is sealed and contains clean air and is termed the referertube. The other tube is called the measuring tube and is used to pass samples through it. Samples adrawn from the crankcase using a fan drawing through a rotary valve. If a large amount of mist is drinto the measuring tube, less light can penetrate the tube to the P.E. cell, so there will be a differencroutput from each sample and depending on the amount of difference will activate an alarm. In the eran alarm, the load of the engine should be reduced immediately by slowing to Dead Slow Ahead andsoon as possible the engine should be stopped and the turning gear engaged. Open the indicator cocturn the engine to prevent seizure. Allow engine to cool to normal operating conditions by observinreturn temperatures.When safe BUT NOT BEFORE 20 MINS the crankcase doors can be opened arcrankcase inspected. A visual inspection from outside the crankcase should be made for signs of wl

metal or excessive oil leakage from bearings or anything which might indicate a problem. If nothingobvious the lubricating oil pump can be stopped and a more detailed inspection carried out.

What immediate action should be taken in the event of a warning being given?Reduce power manually if crankcase mist detector does not do so automatically. Receive permissionthe bridge to stop the engine. Allow to cool down before inspecting the crankcase for signs of the hc(See note 23 Class 4 notes )

What factors must be present for a scavenge air manifold fire to start?Dirry scavenge air trunking.lncorrect amount of cylinder lubricating oil.Defective fuel valve and bad combustion.lncorrect fuel valve timing.Worn piston rings and liner.Choked exhaust.Defective stuffing box. ( See class 4 notes page 20 )

How would you become aware that a scayenge fire had started?Erratic engine speed.High exhaust temperatures.Smell of burning paint.Turbocharger surge.Smoke from funnel.Rise in J.W. temperafire of affected unit.

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How would you deal with a scavenge fire?In the event of a scavenge fire the bridge must be informed, as should the C/E, that the engine has toreduced to D.S. Ahead immediately.Increase cylinder lubrication to all units by increasing the mechanical lubricator flow to mar<imum.Take fuel offthe affected unit by lifting the fuel pump roller or suction valve offits seat ( dependingtype of fuel pump is fitted ). Shut off nozzle cooling(if nozzle is oil cooled ).By increasing lubrication there is less chance of the engine seizing due to being overheated by the firby taking the fuel offthe affected unit the heat developed due to combustion is reduced, which will 1fire more chance of burning itself out.The scavenge drains should be closed to prevent any sparks entering the engine room which c81 posrfurther risk to personnel in the vicinity.Ifthe fire is of amore serious naflrre the engine will have to be stopped, the indicatorcocks opened rturning gear engaged and the engine turned. The scavenge space fixed fire fighting installation can tbrought into use to extinguish the fire.Scavenge spaces should be inspected to ascertain cause of fire before restarting the engine. Personntshould stay clear of relief/explosion doors where fitted.

What factors must be present for an explosion to occur within the starting air pipelines and wllimits the effect of an explosion?Heat. Usually in the form of a leaking air start valve.Fuel. In the form of lubricating oil coating the internal sr:rfaces of the air start lines.Air. Devices for limiting the effects of explosion are.(l) Flame traps. (2) Bursting discs. (3) Reliel

What is meant by the supercharging of a diesel engine and how is this achieved?Supercharging is a means of supplying air to a cylinder at a greater pressure than atmospheric. This ,done on earlier designs by means of scavenge pumps, roots blowers, under piston scavenge systems tDisadvantages with earlier systems were that they used up to 7% of engine power to drive the mechato boost the airpressure. With the introduction of the turbochargerthe above components were phasout, although some installations combine both.

Describe the operating cycles of a two-stroke and four-stroke diesel engine.4-stroke Air inlet valve opens - piston moves down cylinder drawing in air - air inlet valve closes apiston moves up cylinder compressing trapped air - just before piston gets to TDC fuel is injected -expansion of gas forces piston back down cylinder where at BDC exhaust valve opens - piston rloVerup cylinder forcing out exhaust gases ready for the cycle to start over again. One complete cycle takrdegs.

2 - stroke Air enters cylinder through scavenge ports, exhaust valve may still be open on turbocharlengines - trapped air is compressed - just before TDC fuel is injected - combustion takes place andexpansion of the gas forces the piston down the cylinder where the exhaust valve opens to expel theexhaust geNes - the piston uncovers the scavenge ports to allow the fresh charge air into the cylinder .exhaust valve closes and the cycle starts over again. One complete cycle takes 360 degs.Note. The higher the boost pressure the longer the exhaust valve overlap.

Explain the function of a turbo-charger.To boost scavenge air pressure to a pressure greater than atmospheric with no loss of engine power.Volutecasing-Filter-Inducer-Impeller-Difhrser-Rotor-TurbineWheel-NozzleRing--LabyrinGland - Bearings - Oil Pumps/Thrower Rings.

4s' 3:#hiil|]ilHll#Hve a cvlinder liner rrom a rarge two-stroke srow speedRemove alr connections from the cyrinder head.Remove the cylinder head.Remove the piston rod nut.Disconnect stuffing box from diaphragm.Grind off the carbg'l build up on the liner before lifting the piston.Tap out rhe piton lifting bolf holes.Lift the piston from the cylinderRemove the lubricator quilrs from the riner.Fit the liner lifting gear.Remove the liner.

46' Explain how scale forms on the heating surfaces of boilers.If the feed water in high pressure boilers Is nora, pure as possible, three main problems vencountered' These problems are serious and canlead to Lxtensive and ,*p..rri,ne damagrthe ancillaty components and can sometimes lead to injury of ttre engineroom staff, As thil:'F::';ll?::'ffit3frl;Hgi*f loo..tprocedure,*h,ndearingwiththis(1) Scale build up on the inside of the tubes.(2) corrosion of the feed system and the boiler tubes.(3) carry over of soluble salts and suspended salts to the superheater and t'rbine brades.The main cause of the problem is not carrying out proper tests on a regular basis (most shcdaily) to check for ph value, oxygen and co2 levels in the feed water, poor maintenance oftr*lf.:#:t1"1ffiff"::chemicils

to ensure limits are kepno,r,. recommended revels as

Dissolved Solids are salts that dissolve in water, these sarts (chloride salts) are sometimes <boiler walls when there is an unusual concentration of heat.susnended Solids are salts that do not dissolve in water but are carried aro'nd the boiler anwater system in suspension, these particles *r rupf;;;il;;""*.r. (Iron and copper o_x47. Why is the scale undesirable?

(l) corrosion - takes several forms but the most severe cases of oxygen pitting can lead to rfailures' corrosion in the closed feed ,y*.* of high pressure water-tube boilers plantsthe transport of corrosion products of coPPER *o lRoN into the boiler. Hard, iron arffi'H LT:1;ii:,Hi,:'j'#:n::frli,H,'J**";;i, L"',st, giving rise ro an i

(2) Impurities - ( soluble and suspended solids ) - trougt t in with the feed water concentrateilHl"ntually

reach a concentration where soluble salis una susfended salts are .. carried orThis can result in deposits in thl superheater and on the turbine blades.

48' why is the boiler water tested and what tests are made and how often?To ensure the water pH is not acidic and that the chloride *d iDi readings are in the prescrFl*'llXil?d J?filllb;H:3, atri;;ine (e) oD aD phospiat. (ej caustic /

Dailv Boiler Tests.

100 ml sample of filtered boile, *ate,Add l0 drops ofphenolphthalein indicator - sample will turnpink if alkaliniry is > g.4Add sulph'ric acid, strength 0. 02N from a me€rs'red b'rette until the sample goes clear.

ppm CaCo3:ml O.O2N x l0

ChloridesRetain above sampleAdd a few drops sulphtrric acid o.o2N to ensure solution is no longer alkaline.Add 10 drops potassium chromate.Sample will turn yellow.Add silver nitrate from a measured burette until sample just turns a brick red colot'.

Ppm CaCo3 : ml silver nitrate x l0

IDS100 ml sample

ldd l0 drops of phenolphthalein indicator.Neutralise with I drop of acetic acidlT. a sample in pot & fitto conductivity meter.Take a reading of meter - temperature compensate and read offscale.

tLq!@ ( Vanadomolybdate Test )Place 5 ml distilled water in r 0 ml left hana tube.Place 5 ml Boiler water in r 0 ml right hand tube.Top up to 10 $ with reagent- Stopler and shake and allow to stand for 3 mins.Place left hand tube in L.H. side of lovibond competitorPlace right hand tube in R.H. side of lovibond compactorHold up to light and find colour match - take reading of card in ppm.

@ (colourmetrictest)Thoroughly rinse sample bottle with the water to be tested.Arrange tr;rro 50 ml nessler tubes side by sideAdd 0'2 ml of thymol blue indicator soiution from a graduated glass dropper into the R.H. nessler ttAdd 50 ml of sample to the R.H. nessler tube.Add 50ml of sample to the other nessler tube. (This is the blank )Place the sample cylinder in the R.H- compartment of the Nessle riser and the blank cylinder in thecompartment.

ilff,ffilii,fi:#,il;ffiffiTffi:'*.the corours in the rwo windows using a constant right s,

Hvdrazine Reselve.Arrange two 50 ml nessler tubes side by side.Agd 15 ml hydrochloric acid 0.5N ,t "rreilh to each cylinderAdd to the R'H' cylinder by pipette zs iitof sample and mix with a glass rod.Add to the R'H' cylinder by pipette l0ml of dimethyl, amine amine berzaldehyde solution and thorormix.Add to L.H. cylinder by pipene 35 ml of sample and thoroughly mix.

ftfiliifrT::H"ffi,*|" "' cvlinder in the R-H. comparnnent of the nessleriser and the L.H. cyri

Match the samples 4gainst the colo'rs of the disc.Disc readine : ppm hydrazine

ml of sample

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50. Explain how the water level in the gauge glass can be verified as correct.

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what is the purpose of adding chemicals to the boiler water?To increase the alkalinity or thJphosphate reserye or to act as a Coagulant. In other words to maintilimits required by the manufacturer of the boiler and to minimise damage to the plant.

Close 2 &3 and 0pen I - If free flow from gaugethen drain is clear. Open 2 - if free flow steamconnection is clear. (No water level in glass)Close z-------Open 3 - free flow from ar"i", waterconnection is clear. Note gauge glass will be showing full.Finally close 3 and open 2leave io allow gauge glassloretum to working level again then close I and open 3,level may be slightly high until water temperature returnsto normal.

See blowing gauge glass notes 32,33.

If you find no visible water in the boiler gauge glass what immediate action should be takeniIf there is no automatic shut-offof boiler nir to birners then shut-offthe fuel manually. sound thtEngineers alarm and call the Chief Engineer.Blow the gauge glass to see if there is iven the slightest bit of water in the gauge glass. If no waterDo Nor ADD WATER until the correct level oitt. boiler water has been established because ttshock of adding water to overheated boiler tubes could collapse the boiler tubes. It is better to let tlcool naturally to their working temperature.

Why is the presence of oil in the boiler water most undesirable?(a) Cuts down the heat transfer when oil adheres to boiler tubes (internally)(b) Causes priming resulting in water and oil carry over to the superheaters and turbines.(c) Combines with suspended solids in the boiler water to produce sticky deposits.

why should oxygen content of boiler feed water be reduced to a minimum?(A) Attacks on boiler metal resulting in pitting and deposition of iron oxide on the boiler tubes.(B) Corrosion of the condensate system to produce iron and copper** in the condensate.*:$ copper is attacked by ammonia in the presence of oxygen.

How can this be achieved when an open hotwell and feed system is used ?(a) By keeping the hotwell temperature at approx. 90 degs. c. The oxygen content of water at 50 dis approx. FOUR times that of 90 degs C.(b) Ensure deaerator is functioning conectly.(c) Stop air leaks into condenser, condensate system and boiler feed system.(d) Ensure the correct level of Hydrazine is being added to the deaerated feed water.(e) Introduce Amines into the low pressure/temperaftue part of the feed system.(f) BV floating polysryrene balls on top of the tank.

rf the plant is un-manned, what would be provided to raise the alam if the water level in the Itoo low or too high and how often are these tested? r' rsv vv "rr/r rrevrsr r'' rrr' I

Mowbray float alarms. Level transmitters. Tested weekly.Foxboro (Pneumatic) High /Low level trips. Tested *r.kly.

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56' what causes fires to start in boiler uptakes. what are the hazards. How are they deteractions should be taken?Build up of soot deposits are a cause of fires, possibly caused from faulty sootblowers.They are detected with temperafire sensors - thermometers or similar type devices.The hazards are that if left unchecked the fire may develop into a hydrogen fireThe action to be taken is:_1. Shut down the boiler fires and close the air registers.2' Shut down the F.D. fan and ensure vanes are closed. ( also stand by fans )3' Increase feed flow through economisers (if fitted), blowing down the boiler drum as requ

57 ' on a steam ship, what are the main reasons for using the main engine turning gear?To ensure that the heat is evenly distributed while *u*rling through and that turbine rotors cto pressure in the main condenser (underslung varieties ).To aid in gearbox inspections, shaft bearings-etc.

58' Describe how to prepare and flash up a high pressure water tube boiler.1. open drum vents and economiser vents ( if fitted ).2' Fill boiler to one inch in glass. ( enstue all drains on water drum are closed ).3. Open superheater vent. (Recirc ).4. Open drains on superheater headers.5' Set fuel oil rail up onHFO if steam available, otherwise flash up on DO.6. Line up atomising steam.7. Line up forced draught fan.8. Ensure air heater is by-passed.9 ' Flash up the boiler on small tip at lowest rate according to manufactures recommendatiorsteam gradually leaving drurn vent open until steam issues at approx. 2bar.Superheater ventuntil flow is guaranteed.( Boiler on line ).

10. Test all trips putting boiler on line.

59' Describe the warming through procedure required to prepare the main turbines from cto ready to start of manoeuvring including checks and tests.1' Run main lubricatin-s oil purnps ensr:rinfall temperatures and pressures are normal.2. Start the main circulating pump.3. Engage the turning gear.4' open up the gland steam to maint?in u positive pressure above atmospheric at the turbine5' Open the steam to the first stage air ejector. ( mar.vac 10 ins )6' Start the main condensate pump ensuring the condensate re-circ valve is open.7 ' open the auxiliaty exhaust from the auxiiary condenser to the main condenser.8. Ensure all turbine drains are open.9 ' Open warming through by pass valves on the main steam line.

10. Rotate turbines by means of the turning gear.I l ' Gradually increase the main condenser vacuum by slowly opening up steam to the air ejectuntil fully open.12' Adjust gland steam as necessary to keep pressure just above atmospheric.

Check operation of various trips associated with main turbines. i.e. overspeed, low lube oil, lrDepending on the installation there may be various other trips fitted.

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How is the main turbine prevented from over speeding and what trips would need to be reset?The main n'bine has an overspeed trip ( normally . ,pJ"d hmiting u.n to, ) to prevent overspeedcase of a coupling failure or the ship's propellet "I"-irrg the wavm o*ing rough seas. The trip urfitted with three independent circuiis, which sense trre turuine speed by means of pick ups mo'nte,turbine pedestals, aod receive a speed signal from three pulses iroauced by a tootled wheel. Theshuts a number of control valveslo.ut"Jin the steam chlst, which is an internal part of the H.p. tuthe overspeed trip operates, the boiler safety valves may lift, due to a sudden decrease in turbine lowhen the trip operates, the mechanical movement alters the position of the trip switch which thenenergises the upper coil of the relay and at the same instant dL- energises the lower coil, thus chanlposition of the relay. The coil of the solenoid valve is thus de-energised and the spring moves dovthe oil pressure keeping the manoeuwing valve open is lost. Simultaneously visual and audible altactivated and the particular trip is indicated. After the trip has been reset, (the fault being rectified)reset switch is made which energises the lower coil of thl relay, and the solenoid valve is repositio:protection system is thus reset. Any number of trips can be built into the system.

Explain how the final superheated steam temperature is controiled on a high pressure/hightemperature water - tube boiler and why is it necessary.Attemperators are used to keep the final superheat t"mjeran r.s within the desired limits. It is necrcontrol the temperafi[e to protect the superheater tube materials from overheating and to reduce thtdeposits formed on the tubes.

Describe the routine inspection you would carry out before taking over a watch on a mannedroom of a steam ship.See question 33 In addition :_check deareator level, check F.D. fans, bearings etc.,.Check air heaters and economisers.Inspect boiler water levels and automatic combustion controls including fuel oil temperatures andpressures.check around turbine manoeuwing controls lookin g attemperatures and pressures and for signs of rlights etc. (Gagged valves ).Check main condenser vacuum.Check gravity tank overflow sight glass.

Give the various operating pressures and temperatures of a steam propulsion plant you may tfamiliar with.

\ilhy is there a vacuum in the main condenser?There is a vacuum in the main condenser to improve the efficiency of the plant, i.e. to get more worof the steam.

Give reasons why there may be some loss of main condenser vacuum and why is this undesirall' If condensate temperature is below the saturation temperature of the condensri- ai, leakage intocondenser or incorrect operation of the air ejector.2' If cooling water temperature difference is greater than normal - insufficient cooling water, or bloctubes.3' If cooling water temperature is less than normal - Dirty tubes, or in the extreme case, division plawashed away.4' lngress of air at L.P. turbine gland due to insufficient gland steam pressure.

All the above toubles cause a loss of vacuum and raises the exhaust temperatue of the tubine.This loss of vacuum causes a loss of power and a loss in plant efficiency.The efilect of a sudden loss in vacuum will be to lift the relief valves on the flrbines. over pressuThe L'P' turbine and the condenser are undesirable hence a safety device shutting the steam to theflrbines is required.

To continue running under low vacuum condition would mean having a higher exhaust temperattu

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which can cause the L.P. turbine to hog when fitted with an underslung condenser, thus producthermal stesses. The limiting exhaust temperattrre is 77 degs C for cast iron and g2 degs C forcasings.

Loss of Vacuum Tripln order to improve the efficiency of the turbine, the condenser and hence the ttrbine exhaust is rurvery high vacuum (about 730 mm Hg ). This means that the saturation temperature of the steam50 degsC. Ideally a turbine should be designed so that at the exhaust the steam i, dry saturated. SIcondenserpressure suddenly rise i.e. the vacuum fails, then since the heat content of the steam is tland the exhaust steam temperafltre has risen to the new saturation temperatrue, the steam will now I

Thus the exhaust conditions have changed, since instead of dry saflrated steam at about 50 degs Chave wet steam at a temperafttre in excess of this. This change of condition will cause sudden oveof the last few rows of blades, the resulting expansion causing possible blade rubbing. Further to tlwill also be very rapid erosion as the high speed L.P. blades strike the water particles.To prevent this from occurring a vacuum trip is fitted which closes off the turbine steam supply shtvacuum fall below a preset level. ( usuaily about 50% )

Describe the procedure to start up a turbo-alternator from cold until it is ready to be connectswitchboard including trips to be tested and reset.Stan the TA condenser cooling water pump.Circulate air ejector/gland steam condenser (if fitted ) bv means of condensate pump, ensuring reciris open.with the use of the priming pump, pump oil round the bearings and the gearbox sprayers ensuringpressures are registering on the gauges.Raise the condenser vacuum to 60Yoby means of the air ejectors and the gland steam and open up texhaust to the atxiliary condenser.Crack open the master steam valve having first made sure alt nrbine and line drains are fully open.Adjust steam to H.P. and L.P. glands as necessary until small amounts of steam issue from the glan,Check oil levels in the sump and ensure salt water cooling is lined up to the L.O. cooler.overspeed trip should be tested every time the machine is started. one engineer should stand by thtmaster valve while another operates the throttle valve. The L.O. hand pump should be operated to ethe steam confol valve to open and allow steam into the turbine once the throttle valve is cracked oTubine drains can be eased in but not closed. By means of a special tool pressing on the governor Ithe machine can be oversped and the revs noted for the log book. Once the overspeed trip has workdelay re-setting of the trips until machine is at approximatlly 40%of the normal speed. Check L.O.temperatures' Reset throttle/emergency valve and progressively open master steam valve until appnturn open' Bring machine up to full rated speed by means of the throttle valve and ensure master vafully opened' Raise vacuum to morimum. Close all drain valves. Machine is now ready to parallelon board s.w. valves to L.o. cooler etc. can be regulated to suit.Trips fitted are;- overspeed - Low L.o. - Back p-rr*" trip.

What are nodes and anti-nodes?.Within a vibrating system certain points that do not move or have zeroamplitude are called NODESpoints where the amplitudes of vibratory movement are at a ma:<imum are referred to as ANTI-NODHence a bearing would be placed at or €ls near as possible to a NODE.

when coming into port, how do you change over from HFo to Do?The method of changing over from HFo to Do will vary from vessel to vessel but a common methouse of a mixing chamber where-by the viscosity of the iuel is "sensed" by the viscometer and the heautomatically removed from the heater as the DO filters through the system on its way to the fuel oilcool gradually and prevent thermal shock to the materials of the engine block etc.Fuel supplied to motor vessels is usually of the high viscosiry rype.This kind of fuel is a blend of low-viscosity distillate and high viscosity residual oils . The b'nker sr

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has tables which give the proportional amounts of eachkinq of oil required to obtain some specifviscosity' After the proportions have been established the blend is produced by using rwo pumpsaranged to discharge into a common pipe. The size of the pipe is such that turbuleni flow takes 1the two tlpes of oil become will mixto.-th. speed of the two pumps is set so that the proportion rkind of oil passing into the common discharg; is maintained clnectly. Distillates from one crudedo not always blend well with residuals from another. This occurs when the smaller part is not scthe larger part' If incompatible oils are used to produce a blended fuel, precipitation will occur. Tlitself in the operation of the centrifugal purifieis which quickly fill with asphaltic material and exrdifficulty may be experienced in maintaining an adequatl throughput of fuel through the purifier Irequirements of the engine- This problem is well rcnown 1o n et oit suppliers and they take every (blend compatible types of fuel. Normally fuels from different ro*.., should not be mixed aboarblend that is compatible in itself may not be compatible with a blend from another origin, and premay occur.

what is cavitation and where would it appear?Cavitation is the forming and bursting of vapotu-filled cavities or bubbles and it can occur as a respressure variations' Found most commonlron ships propellers due to presswe variations on the bpropeller blades the result being a loss of thrust, erosion of the blade suface, vibration in the afterlthe ship and finally noise- It is usually limited to high speed heavily loaded propellers and is not aunder normal operating conditions with a well designed propeller. Another component subjected tcavitation will be centrifugal pump impellerr, .rprJiuty condensate pumps used in dry-sump cond

which bottom end bolt would you expect to fail first, a bolt fitted to a four stroke engine or afifted to a two stroke engine?Likelihood of bottom end bolt failing on 4-stroke engine first due to the various stresses affecting t(See attached notes)Simple stress:-Comes about from some static form of loading, and the value of the stress does not change.Fluctuatine Stress:-Diesel engines when operating are not subject to static forms of loading . Due to cylinder pressurevariations and dynamic effects of the -orrirrg parts the forces acting on *y part of an engine are a1changing' As the forces change so the stresses in the various parts change. The changing values ofexperienced on parts of a machine are referred to as fluctuatirrg ,t .rr. et any instant in time the vastress can be related to a simple stress.Alternatine Stress:-Is said to occur when the value of a stress changes from some value of tensile stress to a similar valrcompressive stress' The example is the overhung fly.rvheel where a particle in the shaft surface willchange from tensile loading at its uppermost position of rotation to .o*pr.rrive loading at its lowesThe overhwtg flywheel may be considered as a cantilever with a concentrated load.C)'clic Stress:-when a certain pattern of stress change rTeats itself at equal time intervals (for example, each revtof an engine of shaft) the pattern of stress is refened to as cyclic stress.Fluctuating' alternating' of cyclic stresses are of great importance as they are very closely associatera form of failure of machine parts known as fatigue failurl. Alternating of cyclic stresses are sometireferred to as fluctuating stresses as a general t.trn to distinguish them rrorn simple stresses.

How is a fuel oil burner with steam atomisation, prevented from being removed from the boiltthe fuel and steam are still flowing?Mechanical interlock situated on tof of burner i.e. when fuel and steam valves are in the open positiburners are covered and cannot be removed.

what happens when a condenser loses its vacuum?(See question 65)

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73. why should you not run an astern turbin_e on superheated steam for extended periods?Not designed to rur for periods longer than 30 minutes as higher t.*p, involved **ta affect ex1the LP rotor with the added danger or uua. rub and subsequent dam4ge. (Materials & Tolerance

why are intercoolers fitted onto air compressors?

i1'.'ff!,;1h:ffii:'*:"#ffif[:ff#ssed ai,to be cooredafterthe various stages thus ir

Why is boiler furnace air heated?Heating the air prior to entering the furnace increasing the thermal efficiency of the boiler by imprcombustion process.

what safety measures are fitted to protect a steam turbine should a blackout occur?Gear driven pumps on most modern pt*rtr (Stal-Laval) driven offthe main gearbox ( press,re /gasystem) or gravity tanks situated at the top of the engine room provide adequate time to bring the tto rest in the event of a blackout.

Describe turbo-charger surging.Turbochargers sluge when thty are uying to deliver more air than they can suck in. The causes afiusually blocked intake filter, failure to open cooling water valves for the charge air intercoolers. Lbangs are heard from the scavenge tunking. (Not *tit. sonic bangs.)

What is a hi-jet valve?Hi-Jet valve is a PV (pressure/vacuum ) breaker found on all cargo tanks and fitted to prevent vacupressure conditions arising in cargo tanks with possible structural damage resulting to the tank.Flame screens prevent the ingress of sparks, ligirtening etc. into a flamniable atmosphere. The gastbe cleared to 3 meters above the deck.

How do you test main engine trips and how often are these tests carried out?when running up Main Engines various t ips can be tested by simulating the trip devices, i.e. overlow lubricating oil pressure and high Jacket water Temperature.

Describe the process of tran-sferring heary fuel oil from a double bottom tank to a seftling tan** Ullages of all the tanks before "oriro.rr.irrg ** ** Checklists ** ** Oil Record Book *:F* * communications ship to shore,if appropriate or Bridge and engine room senior watchkeeping of** Don't rely on gauges for final ullages itopping off ; -,r*

Record all transfers in log book as wellrecord book 'F* Regular checks ** *tspitt gearat the ready **

Take soundings /ullages of any tanks supplied from the common line. check all valves before conuthe bnnker operation' If necessary lash ctosea any valves which could accidentally be opened. Line.correct transfer line' Inform duty engineer and Bridge that transfer is about to start. start pump and

:1l?',Y:Hi?tr::$j#s to confirm now is conect. Do this on a regurar basis. Have spnr sear

If transfettittg to two tanks at the one time restrict flow to one so as only one tank to monitor whenfinishing.

YnI is the purpose of fuel oil settling tanks?Settling tanks are used to allow any water which may have entered the tank accidentally with the oilleaked via a heating coil to "settle out " where it canbe drained to the oily bilge. They are fitted witlheating coils to allow the oil to be raised in temperature for ease of transfer to the daily service tanknormally through a p'rifier. The temperature should be restricted to app;. 5l deg c ( 125 deg Ftemperahrre should be restricted to approx. 5l deg c (l2s deg F )

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why are weighted cocks fitted to oil sounding pipes?weighted cocks are fitted to oil sounding pipes on aouule bottom tanks ro ensure a positive shut-oIn the unlikely event of the vessel touching bottom and the tank being holed, sea water at pressureenter the tank and displace the oil out via the sounding pipe.

Where and why are quick closing valves fitted in a fuel system and how can they fail to operrQuick closing valves are fiued to the suction lines of all fuel and lubricating oil tanks so that in theof a serious fire in the engine room, the tank can be isolated in the event of the pipeline melting inIt would also allowthe engine to stop due to lack of fuel if the engine room had to be

lnv are oily-water separators necessary in an engine room?See question 14.

What pumps on board ship can be used to pump out engine room bilges?See question I 1.

Give possible reasons why an engine room bitge pump may not be able to empty bilges.See question 12.

What immediate action must be taken if a fire in the engine room is serious enough to have trevacuated by all personnel?See question 6.

Where would you expect to find the emergency fire pump and what is a very important valvemake sure is closed if the pump has to be used?Fire pump usually situated outside of machinery space normally in the Forecastle but sometimes insteering gear comparEnent. When running ensure anchor wash valves are closed to boost pressure.

Describe the procedure, before the start of a voytge, to ensure that the steering gear is operatrsatisfactorily.Check for oil leaks - Check for loose linkages/pins etc. - nrn pumps individually 30 - 35 degs in 2tseconds' Test means of communication betrveen bridge and Sieeti"g gear. If possible test alarms..

what gases may be found in empty bailast tanks?Hydrogen gas may be present, withpossibly C02. Lack of oxygen due to oxidation in the tank.

What is the danger when using a spirit lamp to detect leakage of freon gas?It decomposes in contact with flame io give products which are pungent and poisonous (Chlorine &Phosgene ).

what type of clutch is used on an electric windlass?Dogclutch or electrically operated magnetic clutch.

What means are taken to ensure that the lifeboat engine will start in any climatic conditions srextreme cold?Arctic fuel ( low pour point ) - space Heaters (intrinsically Safe)Insulated engine housing - Electrical glow plugs - ether aerosol can- Anti - Freezein fresh water circsystems.

what means are provided to prevent overspeeding of the lifeboat when it is being lowered?Centrifugal Brake on Falls.94.

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Describe how you would check a BA set.(A) Check all straps on mask are O.K. & check condition of mask glass.@) Press demand valve (button/ lever ).(C) Check boule connections.(D) Check opening of main valve.CE) Turn air on and offagain.(F) Pressure should not drop more than l0 bar in two (2) minutes.(G) Test alarm, press demand valve or hold mask to face and breath.(H) Check tightness of face seal.

Having reassembled a pump you saw water slightly leaking from a gland packing-- would yorup to stop the leak?No. On packed glands it is quite normal to have a slight leakage of water.

97 ' What temperature would you expect on a M.E. exhaust and what deviation would be aUnder full load conditions. - 350 - 400 degs C Marimum of 50 degs differential.

98' What temperature would you expect for the M.E. lub oil in normal seruice?About 40 - 45 Degs c ( outlet 0 - 3s - 40 degs c. (inlet )

99' What temperature would you expect for the M.E. JCW ? What may happen if the temllow?outlet - 65 degs C Inlet - 55 degs C. Too lowthermal shockingmayresult. Leakage of waexpansion pieces with the possibility of water leakage through tf,e sealing rings etc.

100. If the S-'lry'. cooling temp was too low what effect could it have on the M.E?Cools down Lubricating oil, jacket water charge air and if cooled down too much will affectL.O.(cold plugging in L.O. coolers) and cause thermal shocking and cold temperature corrosion.

101- How would you start an auxiliaty diesel engine (manuat)?What would you suspect if the engine failed to start on air?What would you suspect if the engine failed to start on fuel?Take stand-by machine off..auto start',Turn stating handle to stop and open indicator cocks.Check sump and governor oil levels.Lubricate rocker gear with oil can.operate had priming pump and open air start valve.Blow over engine.Run up engine by turning handwheel to "Start" position. When engine is turning at speed tunto "Run" position.Shut air start valves.Check oil and water pressures.Open sea water cooling valves on engine. Startpump if necessary. Check safe flow of fresh,water on flow sight glasses.Switch on alarm/trip panel in control room.Machine is now ready to parallel.

102. What would you do in the event of a scavenge fire?ln the event of a scavenge fire the bridge most be informed as should the Ch. Engineer that .

to be reduced to D. S. Ahead immediately.lncrease cylinder lubrication to all units by increasing the mechanical lubricator flow to maxTake fuel offthe affected units by lifting the fuel pump rollers or suction valve offits seat ( rwhat type of pump is fitted). Shut off nozzle cooling (if nozz,le is oil cooled).By increasing lubrication there is less chance of the engine seizing due to being overheated tby taking the fuel offthe affected units the heat developed due to combustion, is reduced whthe fue more chance of burning itself out.The scavenge drains should be closed to prevent any sparks entering the engine room whichfurther risk to personnel in the viscinity. If the fire is of a more serious nature the engine willstopped, the indicator cocks opened and the turning gear engaged and the engine turned. Thrspace fixed fire fighting installation (C02, steam smothering etc) can be brought into use to efire.Scavenge space should be examined to ascertain cause of fire before restarting the engine. Pshould stand clear of relief / explosion devices where fitted.

103. How often would you inspect the scavenge drains?What do you expect to see coming from the scavenge drains?What scavenge air temperature would you expect?(a) Every watch (b) A little water with possibly a little lubricating oil. (c) Approx. 40 de1

104. How often do you blow gauge glasses on a package boiler?How often do you blow down level transmitters?Package boiler gauge glasses should be tested when put on line and at any time when there isleast once a week to ascertain where the correct level is.Level transmitters should be tested when the boiler is put on line and approx. Once per montJ

105. How often do you blow gauge glasses on a water-tube boiler?How often do you blow down level transmitters?Watertube gauge glasses should also be tested when put on line and in the case of very high tboilers with the bulls eye type of glass can usually be tested on aregular basis, but forthe norpressure boiler gauge glass, great care has to be taken when blowing the glass in case the micand the glass leaks.Glasses should be tested once every two weeks and with twin boiler plants, one boiler every 1Level transmitters should also be tested when the boiler is put on line and approx. every mon

106. Describe how you would start aTlAfrom cold conditionWhy do you use gland steam?What trips do you have on a TIA?How do you obtain a vacuum in the condenser?Why do you need a vacuum?See question 66.

107. Passing the fridge unit you see bubbles in the sight glass, what do you suspect?Large bubbles in the sight glass may indicate that the system is short of gas. When the syste:charged the sight glass should be clear and the discharge pressure normal, depending on the stemperature.Small bubbles in the sight glass accompanied with a high discharge pressure would indicate asystem.

108. How would you remove air from a fridge system?Shut the outlet from the condenser/receiver and allow the refrigerant to be pumped down. Thrwill cut out on high pressure when it is pumped down. The air can then be removed by openithe top of the condenser.

10e' il" ili*::THJhi:l il

"" a svstem, it has a mi\ quariry about it (a) wourd yrEnsue that the t'9' nTfier is opera:ing co:rectly and that the correct gravity disc is bein*iir";illT'ff]].Hhan8ed

the oil should ue it rieht to continue iriuse iithe source r

ffi.iil:r?:*:,fiYi::|,il":Slsincation or the L. o. caused be warer conraminatior

110. Bo'er water tests--what are you looking for?what tests do you carry out on a water tube boiler?why is it necessary. to reduce o{ygen in the feed water?How is the oxygen level ".Au..Jlstate the formurae for the chemicars usedTo check that the Ph of the water is at the recommended value.That the TDS is not roo high.That the chlorides in the boiler water are not too high.

fffr fr: ffn::l;:ff;';;i13: llf: ;"#i;;*" recommended rimit ( Hydrazine readi:

Tests carried out are :_

*t$ilyir:Hfs' TDs' Phosphates, oxvgen and Hvdrazine. caustic alkalinity shourd a

It is necessary to reduce oxygen to prevent corrosion in the boiler fubes, corrosion in the fetcopper is attacked by ammonia in the prescience of oxygrrr. i i;; question 4g ).prevention - Ensure that the deaerator is working efficiently.stop air leaks into the condens.r, ,iniensate system and boiler feed system.Enstre the correct level of Hydrazirr. i, being added to the deaerated water.

111' why do we superheat steam in the boiler and then desuperheat it before use?;:ffi"::tf;lf:'*tlff b"iil;; that the r,.u* "* store more enerry, and arso the steaThe p'rpose of a de-superheater is to reduce the temperature of a quantity of superheated stesuitable for auxiliary services requiJrrg low temp";;r" or sat'ated steam.

ll2- why do you take power cards on a M.E.?How do you work out the poro." p.r cylinder?Power cards are taken to enstue thai eactr cylinder is developing roughly the same amount o:engine is in a balances condition and the exhaust temperatures should be within 50 degs c oI,:ilT;il,:'#Hl,iiil*:#,';,';flH:il:#i:mx*ffi ::,ff diagram,,henThe formula for indicated pb*., is;_

- -

P = Mean Efifective powerL = Length of DiagramA = Area of DiagramN = Number of Strokes

[13' why do you need to cool the air from the T/c before retuming it to the scavenge space?In order to alter its density and increurc irr mass no* to the cylinders. nge space?

The greater the mass of air supp[J;; rh..yrirra.rs; ,h" greater the amounr of fuel which cantherefore the greater the power oboin.a.

14- If the steering system is overroaded wourd it trip out?

mffiilrh:Jn'TJ#iJ*:*ixl.*ffi*H:**rabrethatthemotorkeepsnu

ll5. why is it necessary to have tappet crearance?what would be the effect if th; clearance was too rarge?What would be the effect if the clearance was too small?To allow for the expansion of the materials of the elgine components as the engine warm

Afi]""* operating conditions- Tappet clearance should always be checked when the en1

Too large clearances _(a) Excess noise aro'nd area of the rocker gear

tlJil:#ff:J"_ oo"" tullv causing poisible back pressure and toss in engine thermat

(a) Valve held offseat, once a valve has started to leak, from any cause, the passage of hcarea of the seat causes distortion which then increases the amount of leakage. The ter:valve and seat in the area of the leak rises considerably, the strength of the metal is im1resistance to erosive effect of the hot gases is seriously reduced. buring the combustichigh pressure in the cylinder expand u.ros the location of the leakage at very high ve1

;ffi:"*J$Hfil?:H*T;;ff.10*n, the combustion perioiy increases very r

116. why are there three water supplies to a purifier?Bowl sealing water.Operating water.Control or sludging water.

It7 ' what safefy device would prevent an explosion in the starting air line?Relief valves in the line, bursting discs , flame traps.

118. Explain how a fusible plug workswhen the temperature ortne fusible plug attains a certain point it will rupture and relieve tlline.

119' why is a steam/steam generatorfitted? why does it have a separate feed system?To supply low pressure steam for the auxiliaries. It has a separate feed system so that 4n! cr[HJr"rfi1X-;:ti'.i'j; ,T,jlnot

be allowed back to the boilei water feed which courd ,rrult i

120' If there is excessive water discharging from the purifier what is the problem?Possibly water in the settling tanks, rculing water supply left on.

l2t. How do self cleaning filters work?

122. why are purifiers contained in a separate compartment?To allow the fumes from the oils being separateJio ue extracted by a separate extraction fanfumes contaminating the engine room.

t23' How does a water transducer varve work?In the ALCAP p'rifier it senses the presence of water in the oil discharge and opens a water rrelease the excess water if the purifier is in between sludge cycles ( of 15 mins)

124. what is the purpose for a back pressure in a purifier?To maintain the position of the oilwater interface which has been established by the choice o

125' Explain what safety features are on an electrical starter box?

ff ffi*H:ffifi0;.oo"tted unless the main breaker has been switched off. This is dont

126, Describe the safety features on a main engine switchboard?

127. Give two reasons why an air compressor may run hotAn air compressor may nn hot if the lubricatini oil cooler ( if fitted ) is blocked, or if thereleak, causing the machine to rwt continuously #tnout uuoaaing, or if the suction filter is Iis a problem with the valves.

128. Describe how you wourd test a smoke ararmTo test a smoke alarm' inform the relevant persorurel, pick a time when everyone,s about , raerosol with adapter and spray head.

129. what action would you take if a purifier lost its seal.If the purifier loses it's seal' desludge oil to recirc, fill with seal water, allow oil to enter borEnsuring back pressure is correct. ir rtitt not sealing investigate further by checking correcrbeing used or that the clutch mechanism is not slipping. (Chlck motor/drive speed. )

130. How do you know if a purifier is up to speed.To check purifier is up to speed, check its iell-tale (78 normal depending upon system) and

131' If a tube fails on an exhaust gas boiler would you (a) stop the engine (b) reduce the engcontinue at full speed.If a tube blows in an exhaust gas boiler while at full speed, continue at full speed, bypass boipressure to drop, allowing water to drain to bilge. Flash up aux. boiler and put on line ASAI

132' Describe how you could test the operation of the emergency bilge injection valve.To test-the emergency bilge injection several methods mat be lsed; ;-(a) If the contents of the bilges are clean then the sea water inlet valve may be closed and thtinjection valve cracked open. The bilge water level should be observed to fall.(b) A dam can be erected around the fipe and filled with clean water, then procedure is follc(c) The suction pipe can be disconn""t"a and replaced with a container of .1.* water beneaas in (a) .(d) A quick method would be to attach a piece of rubberjointing or a stout piece of plyrvoodover the suction' The sea water suction is closed and ttre iitge iijection .ru.krd open wherershould be heard to 'clack' against the spindle and the suction gauge of the pump observed toadequate suction.

133. Explain the difference between a purifier and a crarifier.A purifier separates two liquids, a clarifier displaces solids from a liquid. clarifiers are fittedgravity ting or solid prug (stacks have no holes in them)

v^sr^'!

134. what boiler water tests do you carry out?What salts do you test for and what are their chemical fomula?what effect wourd excess hydrazine have?Boiler tests carried out ;- T. D. S. - Chlorides - pH value - p. AlkalinityT . Alkalinity - phosphate Reserve - Hydrazine Reserve.

salts you test for ;- calcium carbonate ( ca co 3 )Sodium Chloride ( Na Ct)Calcium Bicarbonate Ca ( HCO3) 2Magnesium Sulphate MgSO4

Magnesium Chloride MgCL2Hvdrazine ( N2H4) - sodium Sulphate (Na so3) - phosphate ( po4) - Silica ( sio2 )

135' what could be the problem if there_is oil carry over from the purifier?If there is oil carry over from the purifier it may Le due to ross of oil seal (faulty or worn .o,incorrect gravity disc. insufficient back pr.rr*, too slow (e.g. slopping clutch ) or bowl stur

136- At full away what plant changes are made?At full - away ; plant changes (Motor )1. Sea suction from high to low 2. Waste heat unit on line3. power to deck off 4. Extra Geny offor shaft geny on .5. Lub oil to normal amount 6. Arrxy r."u.ng. utower-or.7. Evap on g. Diesel to HFO9. Steering gear to one motor.

(Steam)2. Feed recirc closed.4. Scoop open.6. Steam offdeck.8 Gas air heater on..

1. Change over to bled steam.3. St.By geny off.5. Astern guard valve closed.7. Steering gear to one motor.

137 ' What is the difference between phenolphalein alkalinity and total atkatinity?Total alkalinity is the combined concentrations of Bicarbonates and carbonates or of carbrHydroxides expressed in a common form, usually in terms of calcium carbonate. It is ofter'M'reading.

ir**t#measures the alkalinity caused by the presence of carbonates, hydroxides and p

138' Describe the symptoms of undercharge in a refrigeration system.Where is the sight glass?undercharging of a refrigeration system may be indicated by bubbles in the liquid lone sighpressure at the compressor suction. The room temperafures will also start to rise.

139. Describe how you would recharge a fridge system.when adding gas to an undercharged sysreir, ttt" g* bottle is connected to the filling valveevaporator outlet, loosely. The bottle valve is cracked open to remove air from the connectjtightening the cormection to the filling valve. The bottle should be upright to prevent entrycompressor should be ruuring and charging should continue rurtil trre silrrt glass is full.

140. Describe a fridge cycle.The pressure of the refrigerant gas is increased in the compressor, ( therefore becomes hot ).passed through a condenser where it-is cooled by water or air, and fecause it is still at a higtcondense' The liquid refrigerant is then disnibuted through a pipe network to the expansioncontrols the flow of liquid refrigerant into the evaporato, ( *rfrh i, ut a lower press,re ). Acooled space passes over the evaporator and boils offthe ,rtigri*t ( at the same time cooliThe design is such that all the liquid is boiled offbefore returning to the compressor.

l4l. State the safety devices fitted to a fridge compressor.A. Low pressure cut out.B. Differential pressure switch.C. High pressure cut out.D. safety valve or b'rsting disc depending on the system.

142. Explain different types of pumps.Po sitive displacement.CentrifugalAxial flow.

143. Explain the drive linkage of a purifier.Motor - coupling - centrifugal clutch (friction pads, feroda ) - shaft - bevel gears - worm whpump with shear pin.

144' What type of bilge pump would be fitted to the lifeboat and what would you do if yousuction?A displacement pump of the vane type or diaphragm pump. If suction cannot be attained;- iPutnp worn' if diaphragm type, split in diaphragm. Blockage in the suction line or hole in tlAlso pump may need priming

145. Describe how the main engine lub oil is heated.The main engine lubricating oil is heated via the L.O. pgrifier heater.

146' Describe the difference between a positive and negative cam with respect to starting airpump.The difference between a positive cam and a negative curm with respect to starting air and fu,positive cam is of a circular shape with a protozoon which upon each revolutior, .uur.s an ulOf a plunger in the fuel pump forcing fuel out at pressure. A negative cam is of a circular shvalley, therefore a normally closed piston will drop and henc. op"tr a valve once every revol

147. Where are the auxiliary blowers, where do they take suction from?The auxiliary blowers are situated at the ends of the scavenge trunking and they take their suengine room ventilation fans.

148. Describe the construction of the scavenge space.The scavenge space is constructed by means of a cylindrical tnurking with stiffeners with anauxy blowers mounted on the ends, and non-return reed valves from the charge air cooling s1fixed fire fighting connections, temperature and pressure gauge connections.

149. Why do you have two different air pressures in the scavenge space?There may be different air pressures in the scavenge manifold a.r"1o underpiston scavenge pl

150. What cut outs are fitted to a main engine?l. Low lubricating oil pressure.2. Main engine overspeed trip.3. Crankcase mist detector.4. High J.W. temperature.Depending on plant, other trips may be;- piston cooling pressure cylinder L.O. tank low level

151. If a main engine alarm is activated will the engine stop or slow down?Varies from ship to ship depending on the alarm *tti.t, is activated, but engine will always st,L.O., High J.W. and Overspeed.

152. How does the engine stop after receiving an alarm?On low lub oil the main engine stops when an air signal allows high pressure air to enter the sAnd exert a pressure on a piston which is connected via the pisto;rrd to the governor linkagrThereby shutting the fuel offthe engine and stopping it.The overspeed trip usually consists of a bolt with a ielatively heary head. The bolt is fitted atend of the engine shaft where no torque is transmitted. It is fitted in a space bored out acrossthe shaft. The bolt is held in place by a nut and is supported by a spring. When the engine ovcentrifugal force exerted by the bolt head overcomm-tir t,rppott oift" compression of th. ,p,head in the "thrown " position strikes a trip lever which is alio thrown and shuts offthe engin

153. How do you lift a fuel pump?The term to lift a fuel pump means to lift_the fuel pump c€rm follower clear of the fuel, cam wAttached to the camshaft- This in turn lifts ttre fuet pump plunger and stops any pumping actiin the fuel pump. Therefore no fuel is injected into the ryiinai-r.The means of actually lifting the pump vary depending o1the type of engine.

. 154. How do you reduce sarinity in an evaporator?To reduce the salinity in an evaporator, reduce the level in the shell, increase the temperature :(check vacuum ). If permanent, check condenser for leaks. Drain brine.

155. What are intrinsically safe fittings?Intinsically safe fittings means u pie"" of equipment that will only produce a spark which is livoltage and current and therefore unable to cause ignition.

The effect of an electric arc or spark on flammable vapour is that the heat i'rPzI'\ L'u rr'l"rurrlaDle vapour lS that the heat increases the energy of the vapourand air locally so that particles are activated and madl ready for chemical combination. The eneroisar- "v'vv sv evrr v clrw\r cruLr ula(.le r9aqy IOf CngmlOal CombtnatiOn. Thg enefgiSatiOnreaches a sufficient pitch after a very small time delay so that combustion results. A weak snark (1r,,weak spark or arc may;#ffi,"ililffiTff.,T:P n p ? a t a r i c r l i o o i - ^ 1 o A + ^ . L ^ . c . - - t - -

ffi;;7#*:lT,",H;enOUSh to enmnlcfe fha irrni+i^- a* aL^ ^-r -rrr^ - ' renough to complete the ignition at the end of the delay period.

produced by itIow

tsincapable of i

ffi,,i e n f h p i n c r r - o L f a * ^ - - ^ - l - - ^ ^ ^ - - r . . r ;#.;;:ffi;d;ffiffi';xinvolved Infrincin cqfp fa'.h-i^,,o -^^.-:-^- - -^ r .r ;;;"- t' t"i'a il"],ffi"""f,1]ili3trnower hrr t q lcn thq+ i+ ic . * -Jo : - - - - r -^-^r^r - - r . t -

(Ys I\./l \,tyVf CLlpower' but also that it is made invulnerable to high external energies and other effects.

SITIill:f ?qT*: ir.:yently made to rwo standards of safety;_t- tt+* *"t3::i,**:.T:*"3dfld,

whi.ch;q'i'"' that safery i, mainrained with up to two:Tit type of equipment can be fitted in any hazardous area.

The other standard is given the symbol:_Ex i(b) and the apparatus made to this specification is safe with up to one fault. The Ex i(b) producrnot used in the most hazardous areas.Manufacturers of intrinsically safe apparatus state that this method of protection is suitable for electsupplies at less than 30 volts and 50 millamps. It is used extensively for instrumentation and some rfunctions.care is exercised in design, that capacitance and inductance within the electrical installation is kept rminimum' to prevent storage of "tt"tgy which in the event of a fault could generate an incentive sparEx i systems are isolated from other eiectrical supplies even to the extent that the cables are not pernbe in the same trays as those of other cables-(to prevent induction effects ). systems are eartheprotection is provided by inclusion of shunt aioal safety barriers between hazardous and non-hazardous areas' The safety barriers have current limiting resistors and voltage by-passing zenediodes to prevent excessive electrical energies from reaching the hazardous areas. Neithercertification or marking is necessary if non of the followinfvalues are exceeded in a device: l.A' 20 microjoules, 25 milliwatts. However, great caution is needed when deciding whether aplwill operate within all of these limits, and any associated systems would have to be certified asintrinsically safe.

Flameproof EquinmentIf electrical equipment could be made with pgrfectly gas tight casings, the possibility of gas seeping ibeing ignited by a spark would not be u probl"*. unrotn-"t"ly, seils on the rotating shafts of motorthe operating rods of solenoids are not gas tight. Hermetic sealing of covers is not grraranteed. Gaskjointing can deteriorate and face to face-3oini depend on quality ortrrc machined surfaces and tightufastenings' lnaccurate threads on screwed cover;tints or ctnduit can allow leakage of gas. So to can

deteriorating cement or sealant on inspection windows or insulators.The designers of flame proof equipment recognise that there is a risk of ignition and explossome enclosures and counter this by making the casings strong enough to witrrstand such arAlso, potential flame paths to the outside oitttr casing throug[.ioitrts or seals ere made so rany flame' Normally this is done in joints by makingthem *.iuf to metal with no intentiopossible flame path between the surfaces are made long enough to prevent flame emission,jointing is not used in the actual flameproofjoint. The flamelath through shaft seals is eloa labyrinth design. Special consideration is giu.n to cover fasienings which must be strongwithstand internal explosion, and as far as possible, gas tight. Screws of special material munique design so that ordinary screws cannot be used to ,rpture them. Their heads are pattrkeys.Screw holes must not pierce the casing. ( from Marine Electrical Equipment and practices I

156. Describe how you operate a bulk co2system.To operate a bulk COz system, raise alarm, evacuate space , take a roll call of all personnel,space' all ventilation fans and close flaps. Trip remote fuel valves and use remote switchesDepending on system pull lever and operate tJleus. mechanism.

157 ' What could be the cause of the exhaust temperature of one cylinder reading higher th:If one exhaust temperature on an engine is higirer than the rest the causes may be a scaveng€valve stuck aiar.�, incorrect fuel injection, incorrect rack setting etc.

158' When would you expect to call the Chief Engineer if you are the only engineer on watcIf I was the only engineer on watch I would call the C/eng as per standing orJ"rr, fail*re of rsteering 9etr, if st-by is rutg, fire in the engine room, *ujo, spill, power failure or if in any r

159' Where is the BA set situated? Describe the construction of the safety line. What speci:are present on the line?The BA sets are usually situated at the emergency stations. The safety line has a wire core tlmiddle of it' Specialised fiuings refer to the Lgr tn the line at intervals of one metre. (Chec1

160- How does an air ejector work and what is its purpose?The purpose of an air ejector is to create a vacuum. It works on the venturi principle.

161. How would you deat with a fire in the boiler uptake?Shut off the burners, secure the FD fans and close the vanes, raise the fire alarm and effect b<cooling.DO NOT operate the soot blowers.

162' What are the last drains you would close when flashing up water tube boiler?The last drains you would close would be the superheater drains.

163' What would be the operating pressure and temperature of the fuel oil system?Pressure would be between 5 bar and 8 !* depending on the installation. An average temperi125 deg C but this would depend uponthe quality an; viscosity of the fuel.

164. Describe an insulation test on a 3 phase AC electrical motor?The insulation test on a 3 phase ACilectrical motor is done using a meggar (500v ) to mez*rinsulation resistance between the 3 phase terminals and against ti'e motor casing. Readings shminimum of I megohm.

165. Describe a jerk pump. How does it work?A jerk pump is a displacement pump used on diesel engines to produce high pressure fuel fiduring each engine cycle by having a cam act upon the roller and plunger of the pump to pftsupplied to the pump on its way to the injector.

166' What problems could occur when running F.O. purifier with different types of bunkerWhen rurning the fuel oil purifier with diffeient gpes of bunkers, their different densities ndifferent gravity discs to maintain the seal. The temperatures of the bunkers may have to beDesludging cycles may have to be changed.

167 ' What is the purpose of an intercooler? (Give temperatures and pressures.)what are the probrems of undercooling the charge air?The purpose of an intercooler is to cool the air so more mass per unit volume of air can passway to the cylinders. ( t bar above atmospheric, air at 40 deg C )If the charge air is cooled too much, the u1r -uy reach its deil'poi.rt and depending on the suthe fuel, sulphuric acid may be formed and "oia corrosior, ,o"y attack the iner. Therefore itkeep the charge air temperature above 40 deg c.

168. what safety interrocks are fitted to a lifeboat?Limit switches, centrifugal brakes and harbour pins.

169. Describe how to(a) Lower the lifeboat.Fasten painter to forward bits.Release gnps and clear gnpes. Remove any temporary engine heater cables if used and remo.pins..Lower lifeboat to embarkation deck and pull the lifeboat into the ships side using the bowsinPersonnel can now get into the boat and ielease tricing pennants.Passengers can now get into the boat and then the boat can be released from the ships side usBowsing tackle.Start the lifeboat engine making sure the exhaust pipe cover is removed (if one is fitted) and lLower the lifeboat into the water.Release the falls and release the painter(b) Raise the lifeboat.Connect the lifeboat falls.Hoist the lifeboat to the embarkation deck and stop the engine.Connect the tricing pennants and pull the lifeboat into ttre strips side.Disembark all occupants.Raise the lifeboat onto the davits until the hoist motor is cut out by the limit switches.Hoist the lifeboat up to its secure position by use of the hand wtreet and secure the gripes.Remove the plug and fit the harbour pins.

170. what is (a) The tricing pennant? (b) Bowsing tackle?.Tricing pennant pulls the boat into the side of the vessel when lowered to the embarkation derBowsine tackle is used to allow the boat to be released slowly from the ships side when the tnpennants have been removed after the boat has been fill with personnel.

l7l' Describe the bridge operation and local operation of a watertight door.Bridee operation. The doors are placed on remote control from ttri uriage. If the door is irposition an alarm will sound and a light will flash on both sides of the door for 3Osecs befocloses' Once the door is closed on remote and left on bridge operation, when anybody thenthe visual and audible alarms will operate for the period oltime that the door is open.Local operation. The door should be kept in the closed mode. When passing through it thebe operated to open the door fully. The tperator should then pass ttgough aia ctose the dorhandle on the other side of the door.See M Notice ???

172' Draw the fire main and indicate aII main isolating valves.

173' Explain what you would do before going UMS. How does the patrol alarm work?Check bilges are dry.check all weighted sounding pipe cocks are in place.check all alarms are cleared and that none are gagged.All various compartments i.e. purifier room nte ators are closed.All fire zones are activated.Oil mist detector operating.All welding or burning equipment isolated.Engine room left tidy.All equipment (loose) battened down in case of bad weather.Test UMS alarm.Inform bridge.

The patrol alarm is a system to protect the duty engineer whilst he is alone in the engineroonHis rounds' Upon entering the engine room, tr ui alarm going offwhen UMS, the patrol mactive'Thepatrol man needs to be reset every l0 mins, if not an alarm will sound inthe eng:this alarm is not answered, then after 27 mins the Engineers alarm will be sounded.

174. How is the purifier motor connected to the pump?The oil pump is connected to the purifier by means of a link, held together by a shear pin, thtwas to foul the internals of the pump causing it to jam, the pin would shear causing minimalmotor is connected to the horizontal shaft of the purifier bya centrifugal clutch. The horizonwonn getr, which engages with a bevel gear to drive the vertical shaft and bowl arrangementpump is connected to the horizontal shaft via the shear pin.

175' What safety feature does a turbine have in the event of loss of power?The turbine is safeguarded in way of lubrication in the event of a loss of power (blackout ) bycontrol lubricating oil via an orifice. The tank above the turbine/gearboi i, constantly fillingpump and draining into the bearings of the turbine/gearbox. So in the event of a fail're theresupply of oil to enable the engine to be brought to rest safely without incgrring any damage.

176. What do you look for in fuel tanks?In fuel tanks you would look for water, which may indicate leaking heating coils, bad supply rwater coming back down the vent pipe. (BRAIR)

177. why are the sliding feet at the front of a turbine?

*:113ff fr:L::ioned on the front of the t'rbine to allow for thermal expansion as the ca

178. How and why do you sootblow?The sootblower uses steam or compressed air to blow away soot or any other products of cthe surfaces of the boiler tubes. Sootblowing at regular iniervals will prevent a build up olthe heat transfer thus improving the thermaliffiri.nry of the boiler. Failure to sootblow cbuild up of soot in the uptakes with a resulting danger of fire.

179' Why do you drain the air bottles and what are the dangers if they are not drained?The air bottles should be drained regularly to remove water as the build up of water in the Ito faulty starting of the engine as well as the dangers of corrosion to the internals of the aircarryover from the compressor mixing with the water can also cause problems with the autother components in the starting air system. Problems could also occur in the control air s5

180' How do you know if an air start valve is leaking exhaust gases back throughthe air start line?What are the dangers?If an air start valve was leaking, this would be indicated by high temperatue in the startingcausing paint on the outside of the pipe to burn and discotour ana peel. The leaking valve <noisy and be heard by the watchkeeper: The danger of a leaking air start valve is that of a sexplosion' If a valve is leaking the engine should be stopped immediately and the valve cha

181. Define safe and hazardous zones with regard to a tanker.

182. Where do you use bled steam?

183. What is O.D.M.E?

184' What precautions must you take when recharging a dry powder fire extinguisher?

185' With reference to an astern turbine nozzle---(a) What is the blowdown ratio? (b) Wharpressure? (c) How is the high pressure steam exhausted to vacuum conditions?.

186' How is the air in the scavenge manifold prevented from flowing back through the cool,piston is on the downward stroke?

187 ' Describe how you would withdraw a burner/n ozzlefor cleaning.

188. What is the pur?ose of the vortex plate?.

189' With regard to a bilge system, what is the meaning of the B/5 rule?.Provision is to be made in every vessel to prevent the flooding of any watertight compartmerbilge suction pipe in the event of the pipe 6eing severed o, duiruged by collision or gro'ndirwatertight compartment- Where any part of ru.tr a pipe is situatei n"*rr. to the side of the shthe midship breadth of the ship measured at the levliof the deepest subdivision load water Iduct keel' a non-return valve shall be fitted to the pipe in the *uL, tight compartment contai:end of the pipe.

190' With regard to gas carriers, describe the operation of the gas bumer.Explain boit off inspection?

l9l' Ifr when opening a valve , water hammer occuris. What should be done?When steam lines are shut down it is possible, from various causes, for them to fill with wallowed to enter a line filled with water, the steam starts to move the water down the line.contact with the water eventually condenses and a vacuum is then formed causing the watrback at a very high velocity. The water travelling at that high velocity returns to the valve ,been opened and strikes it with a very heary bl;, often fracn:ring the valve. If the valve fdisastrous results may occur' with the risk of loss of life. ln order to prevent water hammeropen up the drain connections on the steam line which is being brought into use. The waterbe completely drained so that it leaves the line clear. The steam valvi may then be very slil(cracked open) so that the line can be heated and it's temperature brought up to near worki:Any condensate formed during this period drains out of the drains prruiourl-y op"rr"d. As tltemperature rises and the noise from the drains changes to that of a steam bllwthe steam pline can be slowly increased by opening the steam valve firther. Eventually the drains maythe steam valve has been fully opened.

192. what is the pur?ose of taking crankshaft deflections?The purpose of taking crankshaft deflections is to check for crankshaft misalignment.' They should be taken at regular intervals or when damage to the ryuung gr*]propeller, shstnrcture is suspected. They should also be taken prigt ti entering dry d;ck when work on t

il:t*|:flngs is to be carried out. They should then be taken ugin when leaving dry dock r

The crankshaft deflections should be taken with the engine at the same temperature and theloading as near as possible to the same conditions each time.Misalignment occurs due to wear of the main bearings and from distortion of the engine be<possibly from d*ug-. to the ship's stnrcture. It can be detected by measuring the deflectionwebs for each unit of the engine. If misalignment exists the cranlcwebs will open and closeengine is rotated' The deflections are measured by means of a clock or dial gauge fitted betrwebs at a point in line with the outside of the journal furthest from the pin. A spring loadedholds the dial gauge in position.

193. What is the function of the stuffing box?

t94. where and what is the function of the bedplate?

195' What would happen if the exhaust valve of one unit is blocked?

196' what fype of cargo did you carry on LPG ships and what are the temperatures?

lg7 ' What type of cargo did you carry on LNG ships and what are the temperatures?

198' Did you have plastic pipes on your sewage plant? what is the problem if there is no flrthrough them and what would you do?

199' How do you put a piston on a slow speed engine back into the engine, with regards to li

200' What could be the reason for the piston sticking when putting it back?

201' what is the TBN rating as apptied to Lub oil? state suitable TBN ratings for a Lub oa medium speed and a slow speed engine?

202' Describe how you would change piston rings. what would you be looking for?

203. Why would an air compressor run hot?

204. what action wourd you take if an air compressor ran hot?

205. How do you test smoke alarms?

206. what action wourd you take if a purifier rost its sear?

247, How do you know if a purifier is up to speed?

208' How do you control the steam flow through a steam heating coil? By the inlet valve rvalve. Give reasons why.

209' In some instances cleansing agents are used to clean the bilges. what type of cleaninland what are their l. Advantages 2. Disadvantages.

209' How often should the emergency generator and the emeqgency electrical system be trThe recommended time for the iest ".rot

210' when operating in the uMS mode, some classification societies have regulations for tAlarms to be fitted. These types are collected into two groups. what are these group

212- what is the purpose of your rore as a watchkeeper?

213' what could be the problem if the temperature of a cylinder gradually increases ove*

214' what detergents do you use when cleaning the floorplates on your ship? How do theythey affect separation in the OWS?

215' The engine is racing and slowing- A white lnazecan be seen for about l0 miles behindwhat is the probrem and what woutd you do about it?

216' ll"r:ifr

in the boiler is higher than the gauge glass. what is the probtem and what

217 ' when 1:"ry:og^out

pre sailing steering gear checks , what special attention should be rrudder bearing?

218' Name the parts of an ESD 2 boiler and explain the direction of steam flow.

219' It is proposed to blow down a high pressure water tube boiler, what is the first procedrprocess?

220' what is the function of the engine governor? Exptain its operation.

221' rn a slow speed engine, any dirt etc, resutting from blowpast is collected in the scaveng(therefore does not enter the crankcase. wnat happens to blowouts in a trunk piston ersteps are taken to prevent damage to the engio" J"".rrring?

222. what is the purpose of a sootblower? Exprain its operation.

223. what safety devices are fitted to an air compressor?

224. What is the difference between a slow acfing and a fast acting detergent?

225. How does a coalescer work?

226. How can you tell the difference between a coalescer and a filter just by looking at it?

227. What is meant by s6steady flow, and ..eddy flow *?

228. Where do the drains from a wash basin in the engine room lead to?

229. What is meant by a ,,critical speed"?

230. Explain how a turbo charger surges. what is the surge tine?

232' If oil floats on top and the water will sink to the bottom in a bilge well, canrt you just puslowly seeing as the suction is in the water?

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233' What type of pump is the OWS bilge pump? What is the rotor made oI? What is the st