SHIP TECHNOLOGY                                  LGB 11503......SyllabusLGB 11503-Ship Technology SLT.doc                 ...
REMEMBER TO WRITE THE IMPORTANTANT NOTES
SECTION 1- TOPIC 1The principal oceanographic characteristics that make up themarine environment and their relevance to th...
Introduction  OCEANOGRAPHY IN RELATION TO     SHIPS / SHIPPING ACTIVITIES Ship is any large floating vessel capable of cr...
 Oceanography also called oceanology or marinescience, is the branch of Earth Sciences that studies theEarths oceans and ...
ShipsShips are a vital element in the modern world. They still carry some 95per cent of trade. In 1994 there were more tha...
Ships- continued Although one of the oldest forms of transport, ships, their equipment andtheir function, are subject to c...
75% Of Earth Is Covered        By Sea
Arctic Ocean Atlantic Ocean Indian OceanPacific OceanSouthern Ocean
Sect. 1 ME  Lesson Plan No 1- WindWhat Is Wind?; Effect of wind on ship and wavecharacteristics.The wind is a large-scale ...
Sect. 1 ME Describing Wind :• Wind is described with direction and speed.• The direction of the wind is expressed as the d...
Devised by British Rear-Admiral, Sir Francis Beaufort in 1805 based on observations of the effects of the windBeaufort   W...
Gale      Strong galeStorm   Violent storm
Hurricane
Sect. 1 ME  Beaufort Scale• The scale is primarily used at sea, but it useful to anyone  interested in the weather.• In 18...
Sect. 1 ME  Wind Measurement Wind velocities are measured in a horizontal plane, although a definitevertical gust componen...
Sect. 1 MEWind Measurement - continued  Winds are named in accordance with the direction from  which they are blowing. E.g...
Wind and Wave characteristics.The winds affect the maintenance and decay of wavesystems as well as their generation. Waves...
Sect. 1 MEFrontal WindThis can be the most severe of all, although it usually doesn’t last long.Associated mostly with the...
FRONTAL WIND                                cold front                              warm frontFrontal wedging: When a warm...
Sect. 1 MEPressure WindsFormed by the circulation of air around pressure systems, these are themost common winds of our ev...
Sect. 1 MEPressure Winds- continuedThe high-pressure system is usually the gentle one, while the lowpressure brings unplea...
The following weather map is from Australia and shows high and lowpressure air masses with a front moving across the botto...
Weather Report (Sattelite Image)
Sect. 1 MELand and Sea BreezesIn tropical and sub-tropical regions, land and sea breezes occurdaily. The land breeze can b...
Sect. 1 ME         A: Sea breeze, B: Land breeze             Lake - Sea breeze and atmospheric depthA sea-breeze (or onsho...
Sect. 1 ME  Wind Vectors  Wind Vectors indicate wind direction and speed. The black arrows  plotted on this image are wind...
Sect. 1 MEGlobal WindsThere are regular winds around the world. Some blow the same way allyear round such as the “Roaring ...
This creates cell-like patterns of wind around the world, as seenin the diagram to the left.However, winds do not simply b...
Wind is a vital resource. It turns generators that power cities, provides opportunitiesfor sport, and is affects commerce ...
The global wind pattern is also known as the "generalcirculation" and the surface winds of each hemisphereare divided into...
Sect. 1 ME   Lesson Plan No 2- WaveWavesSeawater is effectively incompressible so its density does notvary with depth as s...
Sect. 1 ME    Trochoidal Wave FormThe waves travel is not due to bodily movement of the whole massof water, but is simply ...
Sect. 1 MEWaves - continued  The following definitions are used in describing a wave:  Speed or Velocity (V)  usually expr...
Temperature, Density and Kinematic Viscosity                                                 Sect. 1 METemperature    Dens...
Sect. 1 MELesson Plan No 3- Tides, Current and                           Iceberg Tides Tide is a flow of a large mass of t...
Spring tide                                         Spring tides occur when the                                         su...
Neap tideA tide that occurs when the difference between highand low tide is least; the lowest level of high tide.Neap tide...
Sect. 1 METhe earth rotates on its axis once in 24 hours and each meridian turncomes opposite the moon, so that in each ro...
The effects of tides on maritime activity include:    • It may only be possible to exit and enter estuaries or bays at a  ...
Sect. 1 MECurrentA current is defined as a body of water moving in a certaindirection. Currents, like tides, are controlle...
Sect. 1 MEIcebergsThe immersed volume of an iceberg is always greater thanthe volume above the water and increases with th...
Sect. 1 MELesson Plan No 4- The six Dimension of                 movement of a floating body                              ...
Hogging &Sagging When the vessel is suspended between the crests of a wave equal to its own length, and then; when the ves...
Diagram showing thewreck of the Malaysianship Selendang Ayu,and the double-bottomtank leaksThe ship which is alwayscrossin...
Sect. 1 ME Design of Floating Vehicles The major requirements of the design of a floating vehicle are; • Most importantly ...
Lesson Plan No 5- CorrosionIntroductionAll materials including metals deteriorate. Some deterioratefaster than others, whi...
Sect. 1 ME The cause, effect and prevention of corrosion in the maritime environment .What is CorrosionCorrosion can be de...
Sect. 1 METhe Cause of CorrosionThe basic cause of corrosion is that all metals are inherently unstable. Theyseek self-des...
Sect. 1 METhe Cause of Corrosion in the Marine EnvironmentIn a marine environment, the main factor that influences corrosi...
Sect. 1 MEAtmosphereIn the atmosphere there will be some trace of water in the form of watervapour. This would lead to con...
Corrosion process- electrochemical processThe corrosion process is an electrochemical process whichbegins when the metal r...
Sect. 1 MECorrosion process- Galvanic CorrosionCorrosion is the chemical breakdown of the surface ofthe metal, with conseq...
Electro-chemical corrosion involving wet corrosion- Galvanic corrosion
Sect. 1 METhe prevention of corrosion in the marine environmentThere are several ways in which corrosion can be prevented ...
Cathodic Protection - sacrificial anodeIn the example above, zinc plates are used to induce sacrificial corrosion of the “...
Cathodic Protection – impressed current systems
Protective Coatings of marine structures - Metallic coatings Electroless Plating, Hot Dip Galvanizing, Anodising, Painting...
Sect. 2 ME Lesson Plan No 6- Marine IndustriesMerchant IndustryTransport of Raw Materials:   • Oil- Crude oil is transport...
Sect. 2 METrade  International trade evolved from the need for different  countries to import and export various goods.   ...
Sect. 2 ME                                 Trade Route•   Route 1 – Blue – Atlantic and Indian Oceans - Europe, around Cap...
Sect. 2 MEExamples of trade by sea:     Raw Material       From                     To     Iron ore           South Africa...
Sect. 2 METhe Fishing IndustryThe fishing industry provides an important protein-rich source of food formany populations i...
Sect. 2 METhe Naval Defence IndustryNaval Defence vehicles are needed for:   • Defence for countries   • Defence and prote...
Sect. 2 MEOil & Gas IndustryOil drilling rigs and supply platforms rigsDrilling for oil in the sea became a commercial nec...
Lgb section 1_marine_environment_rev1
Lgb section 1_marine_environment_rev1
Lgb section 1_marine_environment_rev1
Lgb section 1_marine_environment_rev1
Lgb section 1_marine_environment_rev1
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Lgb section 1_marine_environment_rev1

  1. 1. SHIP TECHNOLOGY LGB 11503......SyllabusLGB 11503-Ship Technology SLT.doc Lecturer:......Lesson PlanStandard QA Lesson Plan auzuddin Ayob F Ship Technology LGB11503 SLT.doc B. Eng Marine Eng; M. Eng Materials Sc & Eng
  2. 2. REMEMBER TO WRITE THE IMPORTANTANT NOTES
  3. 3. SECTION 1- TOPIC 1The principal oceanographic characteristics that make up themarine environment and their relevance to the design,construction, operation and maintenance of marine vessels.– Oceanography in relation to ships / shipping activities– The nature of wind, wind description, wind measurement, wind around coast line and the regular global wind.– The nature of waves and swells and their principal effects on ships.– The nature of tides, current and iceberg and their effects on ships and maritime activities.– The six dimension of movement of a floating body and the design of a floating vehicle– The cause, effect and prevention of corrosion in the maritime environment.– Type of marine industries and trade
  4. 4. Introduction OCEANOGRAPHY IN RELATION TO SHIPS / SHIPPING ACTIVITIES Ship is any large floating vessel capable of crossing open waters (i.e. ocean) and carrying materials and goods from one port to another port. In modern times it usually denotes a vessel of more than 500 tons of displacement.
  5. 5.  Oceanography also called oceanology or marinescience, is the branch of Earth Sciences that studies theEarths oceans and seas. It covers a wide range of topics,including marine organisms and ecosystem dynamics; oceancurrents, waves, and geophysical fluid dynamics; platetectonics and the geology of the sea floor.
  6. 6. ShipsShips are a vital element in the modern world. They still carry some 95per cent of trade. In 1994 there were more than 80,000 ships each witha gross tonnage of 100 or more, representing a gross tonnage of over450 million in total. Although aircraft have displaced the transatlanticliners, ships still carry large numbers of people on pleasure cruises andon the multiplicity of ferries operating in all areas of the globe. Ships,and other marine structures, are needed to exploit the riches of thedeep.
  7. 7. Ships- continued Although one of the oldest forms of transport, ships, their equipment andtheir function, are subject to constant evolution. Changes are driven bychanging patterns of world trade, by social pressures, by technologicalimprovements in materials, construction techniques and control systems,and by pressure of economics. As an example, technology now providesthe ability to build much larger, faster ships and these are adopted to gainthe economic advantages those features can confer. MS Oasis of the Seas, the worlds largest passenger ship, was built by South Korean-owned shipbuilding group STX Europe.
  8. 8. 75% Of Earth Is Covered By Sea
  9. 9. Arctic Ocean Atlantic Ocean Indian OceanPacific OceanSouthern Ocean
  10. 10. Sect. 1 ME Lesson Plan No 1- WindWhat Is Wind?; Effect of wind on ship and wavecharacteristics.The wind is a large-scale movement of air caused bydifferences in atmospheric pressure between localities. Air under high pressure moves toward areas of lowpressure. The greater the difference in pressure, the fasterthe air flows. Strong winds can add to the resistance a shipexperiences and make manoeuvring difficult. Beam windwill make a ship heel and create waves. The wave characteristics depend upon the strength ofwind, its duration and the distance over which it acts, whichis called its fetch.
  11. 11. Sect. 1 ME Describing Wind :• Wind is described with direction and speed.• The direction of the wind is expressed as the direction from which the wind is blowing.• Winds have different levels of speed, such as “breeze” and “gale”, depending on how fast they blow. The strength of a wind is classified in broad terms by the Beaufort Wind Scale (Fig.1). The wind velocity varies with height. Beaufort wind speeds are based on the wind speed at a height of 6m.
  12. 12. Devised by British Rear-Admiral, Sir Francis Beaufort in 1805 based on observations of the effects of the windBeaufort Wind Speed Wave WMO*Number Height Effects observed on the sea knots mph description(force) (feet) 0 under 1 under 1 - Calm Sea is like a mirror 1 1-3 1-3 0.25 Light air Ripples with appearance of scales; no foam crests 2 4-6 4-7 0.5 - 1 Light breeze Small wavelets; crests of glassy appearance, not breaking 3 7 - 10 8 - 12 2-3 Gentle breeze Large wavelets; crests begin to break; scattered whitecaps 4 11-16 13-18 3½ - 5 Moderate Small waves, becoming longer; numerous whitecaps breeze 5 17-21 19-24 6-8 Fresh breeze Moderate waves, taking longer form; many whitecaps; some spray 6 22-27 25-31 9½-13 Strong breeze Larger waves forming; whitecaps everywhere; more spray 7 28-33 32-38 13½-19 Near gale Sea heaps up; white foam from breaking waves begins to be blown in streaks 8 34-40 39-46 18-25 Gale Moderately high waves of greater length; edges of crests begin to break into spindrift; foam is blown in well- marked streaks 9 41-47 47-54 23-32 Strong gale High waves; sea begins to roll; dense streaks of foam; spray may begin to reduce visibility 10 48-55 55-63 29-41 Storm Very high waves with overhanging crests; sea takes white appearance as foam is blown in very dense streaks; rolling is heavy and visibility is reduced 11 56-63 64-72 37-52 Violent storm Exceptionally high waves; sea covered with white foam patches; visibility further reduced 12 64 and 73 and 45 and Hurricane Air filled with foam; sea completely white with driving spray; over over over visibility greatly reduced Fig. 1 Beaufort Wind Scale ( note :1 knots = 1.852 kmph)
  13. 13. Gale Strong galeStorm Violent storm
  14. 14. Hurricane
  15. 15. Sect. 1 ME Beaufort Scale• The scale is primarily used at sea, but it useful to anyone interested in the weather.• In 1805, Admiral Sir Francis Beaufort (of the British Navy) devised the following scale of wind velocity.• The numbers are arranged in sequential order, with a low value zero to a high value of twelve.
  16. 16. Sect. 1 ME Wind Measurement Wind velocities are measured in a horizontal plane, although a definitevertical gust component exists. The term ‘velocity’ indicates direction andspeed, although not all wind velocities measure in both quantities. Ananemometer is used to measure speed and the direction of the wind. A hemispherical cup anemometer of the type invented in 1846 by John Thomas Romney Robinson
  17. 17. Sect. 1 MEWind Measurement - continued Winds are named in accordance with the direction from which they are blowing. E.g. a southerly wind is blowing from the south. Wind direction is measured in a clockwise direction from North, either in 360o, eg. spanning 45o, 22.5o or 11.25o. Fig. 2 Wind Direction North West Wind South Wind
  18. 18. Wind and Wave characteristics.The winds affect the maintenance and decay of wavesystems as well as their generation. Waves are built by thesurface friction between the wind and the water or sea.A short, sharp blow will cause steep, but shallow wavesknown colloquially as a chop. A wind of longer duration will build up longer, larger wavesthat are less steep and less inclined to break.There are three basic wind forms experienced aroundcoastline; frontal wind, pressure wind and land and seabreezes.
  19. 19. Sect. 1 MEFrontal WindThis can be the most severe of all, although it usually doesn’t last long.Associated mostly with the onset of a cold front, this wind will blow veryhard and very strong initially and come in with a sudden impact. But it willblow itself out very quickly, the worst often being over in less than an hour.If the cold front is severe, there is usually prior warning in the form of skysigns. A build up of cumulonimbus clouds, often with lightning and thunder,appears in the Southern and Western skies.Just prior to the onset of the storm, when the sky will probably resemble aboiling cauldron of grey to black cloud, the wind will die right away. This isthe proverbial calm before the storm, because within minutes the frontalwind will race down in a line across the water, at speeds probablysomewhere between 40 and 60 knots. Temperature will drop considerablyas the cold air comes in, there may be rain, hail, lightning and thunder, andthe wind will blow hard for probably 20 minutes to half an hour before itbegins to ease. It will probably blow itself out within the hour.
  20. 20. FRONTAL WIND cold front warm frontFrontal wedging: When a warm air mass and a cold air mass collide, you get a front.Remember how low-pressure warm air rises and cold high-pressure air moves into its place?The same reaction happens here, except the two forces slam into each other. The cold airforms a wedge underneath the warm air, allowing it to basically ride up into the troposphereon its back and generate rain clouds. There are four main kinds of fronts, classified by airflowmomentum. In a warm front, a warm air mass moves into a cold air mass. In a cold front, theopposite occurs. In a stationary front, neither air mass advances. Think of it as two frontsbumping into each other by accident. In an occluded front, a cold front overtakes a movingwarm front, like an army swarming over a fleeing enemy.
  21. 21. Sect. 1 MEPressure WindsFormed by the circulation of air around pressure systems, these are themost common winds of our everyday life. They are fairly predictable inthat they rotate around high and low pressure systems.On the weather map the isobars, or lines of pressure, indicate theirdirection and approximate intensity: • winds circulating clockwise around a high-pressure system in the Northern Hemisphere. • winds circulating anti-clockwise around a low-pressure system in the Northern Hemisphere. • vice versa in the Southern Hemisphere. Northern Hemisphere Isobars
  22. 22. Sect. 1 MEPressure Winds- continuedThe high-pressure system is usually the gentle one, while the lowpressure brings unpleasant winds. As with the other winds, both areunpredictable and often the area between a high and low-pressure centreis squeezed to create a sort of wind race or channel through which thewind increases speed considerably.This is indicated on the weather map by the closeness of the isobar lines.The spacing of the isobars is the indication of the gradient of the pressureand thus the speed of the wind. The closer together the isobars, thestronger the wind. Unlike frontal winds, the pressure winds do not come inwith a great slam. They are probably more dangerous to offshore boatsbecause they blow steadily and consistently for long periods and thusbuild up heavy and dangerous seas. They are more predictable as theyhave a steady increase in wind speed over a period of hours rather thanarriving with the sudden impact of the frontal winds.
  23. 23. The following weather map is from Australia and shows high and lowpressure air masses with a front moving across the bottom of the country.There are strong winds (isobars close together) around the coast but not inthe middle of the continent, which is typical for this large land mass.
  24. 24. Weather Report (Sattelite Image)
  25. 25. Sect. 1 MELand and Sea BreezesIn tropical and sub-tropical regions, land and sea breezes occurdaily. The land breeze can be virtually ignored since it is quite agentle offshore zephyr.Refer to online guide – Forces and Windshttp://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/land/crc.rxml
  26. 26. Sect. 1 ME A: Sea breeze, B: Land breeze Lake - Sea breeze and atmospheric depthA sea-breeze (or onshore breeze) is a wind from the sea that develops over land nearcoasts. It is formed by increasing temperature differences between the land and waterwhich create a pressure minimum over the land due to its relative warmth and forceshigher pressure, cooler air from the sea to move inland. Generally, air temperature getscooler relative to nearby locations as one moves closer to a large body of water.[1]
  27. 27. Sect. 1 ME Wind Vectors Wind Vectors indicate wind direction and speed. The black arrows plotted on this image are wind vectors. These vectors indicate direction and intensity of the wind. The vectors point in the direction to which the wind is blowing and in this image, winds are primarily blowing from west to east. Intensity of the wind is conveyed through the size of the vector. The longer the arrows, the stronger the winds.Atmospheric PressureRefer to online guide: http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/fw/prs/def.rxml
  28. 28. Sect. 1 MEGlobal WindsThere are regular winds around the world. Some blow the same way allyear round such as the “Roaring Forties” south of Australia. Otherschange their direction depending upon the season. These winds arevery strong and are collectively called trade winds because they havebeen used by trading ships for thousands of years.In the days of sailing ships, winds were essential, and sailing with thewind behind you was much quicker and easier than trying to sail into astrong head wind.The same principal still applies today even though the engine drivenships do not rely on wind power. However modern ships are so largeand have such high square profiles that strong winds have a huge effecton fuel consumption and time taken for a trip. This affects the costs ofthe journey and in an industry where profit is all important, it isfundamental for all ship owners and masters to be aware of the globalwinds.
  29. 29. This creates cell-like patterns of wind around the world, as seenin the diagram to the left.However, winds do not simply blow in straight lines from north tosouth. Instead, they are bent by the spinning of the Earth:to the right north of the equator, andto the left in the south.
  30. 30. Wind is a vital resource. It turns generators that power cities, provides opportunitiesfor sport, and is affects commerce as ships sail from port to port. Understanding theglobal wind patterns can be both advantageous and necessary for industry thatdepend on the winds energy. To understand the global wind patterns it is best to firstview the Earth as a fixed (non rotating) planet. view the Earth as a fixed (non rotating) planet
  31. 31. The global wind pattern is also known as the "generalcirculation" and the surface winds of each hemisphereare divided into three wind belts:•Polar Easterlies: From 60-90 degrees latitude.•Prevailing Westerlies: From 30-60 degrees latitude (akaWesterlies).•Tropical Easterlies: From 0-30 degrees latitude (akaTrade Winds). view the Earth as a rotating) planet.
  32. 32. Sect. 1 ME Lesson Plan No 2- WaveWavesSeawater is effectively incompressible so its density does notvary with depth as such. The density of water varies withtemperature and salinity; as does its kinematic viscosity. Thedensity of seawater increases with increasing salinity.The term sea waves is applied to waves generated locally by awind. When waves travel out of the generation area they arecalled swell waves. Waves carry energy and are random inheight, length, and direction. The wave form depends upon depthof water, current and local geographical features.All deep sea waves follow the same shape regardless of otherdifferences. That shape is a trochoid. A trochoid is defined as thecurve traced by a point fixed on a circle as the circle rolls along astraight line. The standard wave form is a trochoidal wave and itis used for all naval architecture and ship structure calculations.
  33. 33. Sect. 1 ME Trochoidal Wave FormThe waves travel is not due to bodily movement of the whole massof water, but is simply constant rotation of points in circles in definitepositions. This motion applies to every particle in the wave, and isthe reason why any floating platform can be unstable.
  34. 34. Sect. 1 MEWaves - continued The following definitions are used in describing a wave: Speed or Velocity (V) usually expressed in knots is the speed at which individual waves travel. Length (L) is the horizontal distance between successive crests or successive troughs. Period or Time (T) expressed in seconds is the time interval required for the passage of successive crests or successive troughs past given point. Height (H) is the vertical distance between the top of a crest and the bottom of a trough.
  35. 35. Temperature, Density and Kinematic Viscosity Sect. 1 METemperature Density (kg/m3) Kinematic Viscosity o C (m2/sX106) The appearance of a rough Fresh Salt Fresh water Salt water water water sea holds little promise that0 999.8 1028.0 1.787 1.828 the effect of waves on the10 999.6 1026.9 1.306 1.354 behaviour of a ship can be20 998.1 1024.7 1.004 1.054 predicted with any degree of30 995.6 1021.7 0.801 0.849 certainty. There are two very importantCode Description of sea Wave height (m) effects causing this problem,0 Calm (glassy) 0.00 one, that waves cause a ship1 Calm (rippled) 0.00-0.10 to roll and pitch and the other,2 Smooth (wavelets) 0.10-0.50 that waves break on board.3 Slight 0.50-1.25 These will affect ship motions,4 Moderate 1.25-2.50 shipping water, structural loading and loss of ship5 Rough 2.50-4.00 speed.6 Very rough 4.00-6.007 High 6.00-9.008 Very high 9.00-14.009 Phenomenal >14.00
  36. 36. Sect. 1 MELesson Plan No 3- Tides, Current and Iceberg Tides Tide is a flow of a large mass of the sea due to a rise in sea level, which is caused by the gravitational effect of the sun and the moon on the earth. The moon exerts about twice the pull of the sun since it is so much nearer to the earth. The amount of attraction varies inversely as the square of the distance, and the moon attracts the part of the earth, which is nearest to it more strongly than the parts, which are farthest away. When the earth, sun and moon are in line their combined pull produces the largest movement of the water, the spring tides. When the three bodies are at right angles this gives the smallest movement, the neap tides. This happen fortnightly intervals.
  37. 37. Spring tide Spring tides occur when the sun and moon are directly in line with the earth and their gravitational pulls reinforce each other.The exceptionally high and low tidesthat occur at the time of the new moonor the full moon when the sun, moon,and earth are approximately aligned.
  38. 38. Neap tideA tide that occurs when the difference between highand low tide is least; the lowest level of high tide.Neap tide comes twice a month, in the first and thirdquarters of the moon.
  39. 39. Sect. 1 METhe earth rotates on its axis once in 24 hours and each meridian turncomes opposite the moon, so that in each rotation of 24 hours there are 2high and 2 low tides with roughly six hours between a high tide and thenext low.This periodic rise and fall of the ocean waters is most noticeable on shoreswhich shelve gradually and expose a wide expanse of beach between highand low water tide levels. The influence varies directly as the mass andinversely as the cube of the distance.Large differences in tidal range occur at different locations along the oceancoast due to: • secondary tidal waves set up by the primary tidal waves • the mass of water moving around the earth • the depth of shoaling water • the configuration of the coast.
  40. 40. The effects of tides on maritime activity include: • It may only be possible to exit and enter estuaries or bays at a certain time. For example, a large ship can only enter a port at high tide. • Launching times. • The maximum load the ship can carry. • Fishing - because fish follow the current and tides. • Design of the waterline of the ship. • High tides needed to clear bars, reefs etc under water.
  41. 41. Sect. 1 MECurrentA current is defined as a body of water moving in a certaindirection. Currents, like tides, are controlled by thegravitational forces of the moon and the sun. In summersome currents will flow in one direction, then in winter theywill flow the opposite direction.Throughout the worlds oceans, there are a number ofsignificant currents which have been used by ships forthousands of years. Vikings and ancient greeks knew thetimes of year to travel with the currents and make theirsailing/rowing much easier. Modern ship owners use thesame information to allow for more economical travel.Fishermen throughout time have also used the currents fortheir benefit. Fish, large and small, follow the currents astheir food sources are also carried along by the currents.
  42. 42. Sect. 1 MEIcebergsThe immersed volume of an iceberg is always greater thanthe volume above the water and increases with the age ofthe ice. Only 10% of the real size can be seen on the surfaceof the water and the other part remains under surface ofwater.The effects of iceberg on maritime activity include: • Sea level / tides – the melted ice will increase the sea volume so the sea level will increase flooding the low area nearby. • Sea road – usually the ship will use the safest way to travel. • Material used for ship’s hull – thicker plate metal used for ship’s hull. • Type of ship – there are icebreaker ships to break the iceberg to ease the ship’s passage.
  43. 43. Sect. 1 MELesson Plan No 4- The six Dimension of movement of a floating body • Heave • Yaw • Pitch • Sway • Roll • Surge(Relevance of oceanography characteristics i.e wave, wind, current, etc. to ship behavior)
  44. 44. Hogging &Sagging When the vessel is suspended between the crests of a wave equal to its own length, and then; when the vessel is suspended on just one crest at midships. In the first case the hull will tend to sag and this is known as the sagging condition. In the second case, the hull tends to hog and this is known as the hogging condition.
  45. 45. Diagram showing thewreck of the Malaysianship Selendang Ayu,and the double-bottomtank leaksThe ship which is alwayscrossing the oceans willencounter bad weather,rough sea with big wavesand experienced hoggingand sagging. Due to the Aerial view of Selendang Ayu, broken in half off Unalaska Island.weight of cargo onboardthe process of hoggingand sagging will make thehull of ship crack at thejoining part andeventually the ship will bebroken into two parts.
  46. 46. Sect. 1 ME Design of Floating Vehicles The major requirements of the design of a floating vehicle are; • Most importantly being afloat. • Structurally withstand the forces of the ocean. • Enable cargoes, passengers and crews to be carried safely. • Enable it to operate efficiently and economically. • Provide satisfactory conditions for habitation.(Relevance of oceanography characteristics i.e sea, wave, wind to ship design)
  47. 47. Lesson Plan No 5- CorrosionIntroductionAll materials including metals deteriorate. Some deterioratefaster than others, while some deteriorate more than others.This gradual process of deterioration or degradation is calledcorrosion and it affects the metals used in ship construction. All metals will corrode on contact with water and air. Effectivecoating and minimisation strategies are essential to theshipbuilding industry and the effective life-span of thecomponents they manufacture.The reduction or minimisation of corrosion is of vitallysignificant in determining the potential life span and suitabilityof materials to be used for shipbuilding, outfitting requirementsand structural applications.
  48. 48. Sect. 1 ME The cause, effect and prevention of corrosion in the maritime environment .What is CorrosionCorrosion can be defined as ‘the destruction of metal bychemical or electrochemical reaction within itsenvironment’. Also, it can be defined as ‘the conversion ofmetallic iron to a mixture of oxides and other compounds,resulting in a change in appearance and reducing itsstrength’.To reduce the waste of materials by corrosion, the correctmaterials must be selected, and protection and corrosioncontrol is needed.
  49. 49. Sect. 1 METhe Cause of CorrosionThe basic cause of corrosion is that all metals are inherently unstable. Theyseek self-destruction by reacting with their environment, forming metalcompounds to obtain the stable state of low free energy. This is the state ofmetal found in nature. This instability will demand the metal to return to thecombined state. The rate at which they seek self-destruction will depend onthe environment. The result is corrosion product known as rust.Basically, metals and compounds in the environment can react with eachother to form another compound of much lower free energy. Thisinteraction is very likely to take place since systems universally tend toseek a low-energy situation. reduction oxidationMetallic mineral → Metal → Corrosionproducts (extraction) (corrosion)The above diagram is the simplification of the process, which converts metalliccompounds or minerals to metal, and back to metallic compounds as corrosionproducts.
  50. 50. Sect. 1 METhe Cause of Corrosion in the Marine EnvironmentIn a marine environment, the main factor that influences corrosion isthe environment itself.There are several causes of corrosion in the marine environment, suchas: • aqueous corrosion in which the metals in contact with sea water • atmospheric corrosion of metals exposed on or near coastlines • hot salt corrosion in engines operating at sea or taking in salt- laden air.Corrosion by seawater or aqueous corrosion, is an electrochemicalprocess. All metals and alloys, when in contact with seawater, have aspecific electrical potential (corrosion potential) at a specific level ofacidity or alkalinity in the water.Marine vessels are exposed to the atmosphere, fresh water andseawater. In each of this element of the environment, there exist alarge range of conditions, which may be corrosive.
  51. 51. Sect. 1 MEAtmosphereIn the atmosphere there will be some trace of water in the form of watervapour. This would lead to condensation that will produce droplets ofwater or a continuous film in the case of extreme humidity. Metals willreact with condensations and form corrosion product.Aqueous CorrosionAny kind of water (domestic and industrial) can give rise to corrosion.The same process as described previously will occur if metal and watercome into direct contact .SeawaterSalt corrosion is mainly encountered in marine environments. Seawatercontains a wide range of salts for example, sodium chloride, magnesiumfluorides and calcium bromides. Because of the high chloride content,seawater corrodes most metals. The salt content also gives rise to higherelectric conductivity than fresh water.
  52. 52. Corrosion process- electrochemical processThe corrosion process is an electrochemical process whichbegins when the metal reacts to its environment and its atomsare exposed to the moisture filled atmosphere, giving upelectrons and releasing positively charged ions into themoisture filled solution which become electrically conductive,and is called an electrolyte. The point of corrosion is called anAnode.
  53. 53. Sect. 1 MECorrosion process- Galvanic CorrosionCorrosion is the chemical breakdown of the surface ofthe metal, with consequent loss in thickness andstrength. Galvanic corrosion is very much like corrosionin the marine environment, but bear in mind thatcorrosion can also take place if only one metal ispresent. When two different metals are electrically connected,an electric potential exists between them. In thediagram, the two metals are copper and steel.Seawater will act as electrolyte in this process.Because of the electric potential, base metal, in thiscase the steel, tends to release its electron andbecome an ion. The electron will travel to the cathodeor the noble metal. The conventional current will flowthe other way round the circuit. At the cathode, theelectrons ionise oxygen and water molecules andwhich become hydroxyl ions. The cathode will beprotected from corrosion. Electro-chemical corrosion involving wet As the process continues, steel will continuously corrosion (Galvanic Corrosion)breakdown into ions that will change its thickness and (Galvanic corrosion is a commonhence strength. This process will continue until the problem when dissimilar metalspotential between the metals is no longer capable of are immersed in seawater in aionising the base metal and corrosion stops. marine environment, and an electrical connection is made)
  54. 54. Electro-chemical corrosion involving wet corrosion- Galvanic corrosion
  55. 55. Sect. 1 METhe prevention of corrosion in the marine environmentThere are several ways in which corrosion can be prevented and controlled. Ingeneral, the first level of protection is control of the metal - which means the use ofthe correct metal for the job. The second level is control of the environment; either bymodification or exclusion from contact with the metal.The final control is through the design – avoiding designs in which the kinetics ofattack on one metal is stimulated by another and avoidance of design, which lead tolocalized attack, impingement and cavitation etc.Corrosion prevention methods used in seawater include: • methods based on protective coatings (isolation from seawater) • impressed voltage or coupling to sacrificial anode (changing the potential of the metal) • passivation of metal (using corrosion inhibitors) -hard non-reactive surface film • changing the pH of the local environment (using chemical) • methods based on modification of metal or change to more corrosion resistant material.Most corrosion-resistant metals rely on hard non-reactive surface of oxide film toprovide protection against corrosion (passivation of metal) .If the oxide is slightlyadherent, stable and self-healing, as on many stainless steels and titanium, then themetal will be highly resistant to corrosion. If the film is loose, powdery, easilydamaged and non-self repairing, such as rust on steel, then corrosion will continueunchecked. Even so, the most stable oxides may be attacked when aggressiveconcentrations of hydrochloric acid are formed in chloride environments.
  56. 56. Cathodic Protection - sacrificial anodeIn the example above, zinc plates are used to induce sacrificial corrosion of the “below the waterline” components such as hull, stern, propeller and rudder areas.
  57. 57. Cathodic Protection – impressed current systems
  58. 58. Protective Coatings of marine structures - Metallic coatings Electroless Plating, Hot Dip Galvanizing, Anodising, Painting etc.
  59. 59. Sect. 2 ME Lesson Plan No 6- Marine IndustriesMerchant IndustryTransport of Raw Materials: • Oil- Crude oil is transported by sea in oil tankers • Iron Ore- Iron ore is transported by ship in the form of crushed rock. It stows at about 0.4 – 0.5 m3/tonne and is one of the densest materials carried by ship. • Coal - Coal stows at about 1.2 – 1.4 m3/tonne and is carried mainly in bulk carriers of more than 40,000 dwt. • Bauxite- Bauxite stows at about 0.7 – 1.1 m3/tonne and is carried usually in medium size carriers or multi-deck cargo vessels.Transport of Manufactured Goods: Steel, Engineering Components, Electrical and ElectronicComponents,
  60. 60. Sect. 2 METrade International trade evolved from the need for different countries to import and export various goods. Approximately three quarters of the world’s trade is moved by sea transport. There is no country in the world that is totally self sufficient, they all import something. Some countries, such as Japan, Singapore, Brunei and Papua New Guinea are highly dependent on imported goods.
  61. 61. Sect. 2 ME Trade Route• Route 1 – Blue – Atlantic and Indian Oceans - Europe, around Cape of Good Hope (Sth. Africa), around Australia (anti-clockwise), Japan.• Route 2 – Red – Atlantic and Pacific Oceans – Europe, around Cape Horn (Argentina), Japan• Route 3 – Green – Atlantic and Pacific Oceans – Europe, Panama Canal, Japan• Route 4 – Pink – Atlantic Ocean, Red Sea and Pacific Ocean – Europe, Red Sea, Suez Canal (Egypt), India, Asia, Japan• Route 5 – Blue Dash – Atlantic Ocean – Europe, United States of America• Route 6 – Blue Dash – Pacific Ocean – United States of America, Japan
  62. 62. Sect. 2 MEExamples of trade by sea: Raw Material From To Iron ore South Africa Australia Japan Scandinavia USA USA Europe Grain Canada Malaysia Australia South America Oil Malaysia USA Timber Indonesia Japan USA Australia Scandinavia Coal South Africa England Eastern Europe Malaysia USA Western Europe Australia Japan
  63. 63. Sect. 2 METhe Fishing IndustryThe fishing industry provides an important protein-rich source of food formany populations in the world. This is due to the fact that ¾ of the land ofthe world is surrounded by sea making fish readily available.The major Malaysian fishing areas are: Endau, Mersing, Penarik Village,Merchong Village, Pulau Perak, Pulau Labuan, Pulau Mabul, Seas offKota Kinabalu, Kudat, Miri, Tanjung Karang, Sungai Besar, Bagan Datoh,Lumut and Penang.There are four main countries that have relatively large fishing fleets:JapanNorwayIndonesiaCalifornia(a state of America) - product from deep sea.
  64. 64. Sect. 2 METhe Naval Defence IndustryNaval Defence vehicles are needed for: • Defence for countries • Defence and protection of main trade routes from the pirates, which rob the merchant ships. • Protection for fishing vessels from pirates • Prevention of fishing vessels trespassing and crossing the country’s fishing border. • Protection of offshore rigs and oil platforms.
  65. 65. Sect. 2 MEOil & Gas IndustryOil drilling rigs and supply platforms rigsDrilling for oil in the sea became a commercial necessity as the land supplies of oilbecame restricted. Drilling ships and rigs firstly sunk bores to establish the supply. Thedrilling platform does not sit on the seabed but floats on submerged tanks at the end oflegs at each corner of the platform.Propellers all around the rig connect to satellite positioning equipment keep the shipabove the bore hole to an accuracy of a few meters. Although in heavy seas drilling mustbe stopped.When the rig is drilling in a water level of several hundred meters this would beconsidered a very accurate positioning system. When oil has been located the well headmust be tapped to allow the drilling rig to move on.This is done by capping the well head on the sea bed with a device known as aChristmas tree. The Christmas tree is simply a manifold with several valves constructedof stainless steelOil Production PlatformThe oil production platform simply contains pumps and tanks for removing the oil totankers or monitoring flow through a pipeline to shore. The production platform hasaccommodation for the crews who are flown on and off as tours of duty are completed.

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