Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
answers for chapter 1-4 (official question catalogue)
#1
Chapter 1 ... question catalogue

1. Mention 4 reasons to design a ship with a good streamline.
2. What is the difference between the linesplan of an orca and that of a ship?
3. Mention 3 reasons why steel replaced wood as a shipbuilding material. (Rec.: From 1880 until 1905 iron was used and later steel.)
4. Which construction method is called clinker-built?
5. Which construction method is called carvel-built?
6. What is the difference between the skeleton-building and the scale-building method of ships?
7. What is TEU?
8. What is a Feeder?
9. What is a VLCC?
10. Mention 3 functions of a supplier.
11. What is a squarebox-ship?
12. What is a bulkcarrier?
13. What is a Ro-Ro ship?
14. Make a sketch of the general arrangement of a cargoship.
15. Which construction materials can be used for the ship’s hull?
16. What is the difference between iron and steel?
17. Which element is added to the steel-alloy to improve the tensilestrength of the material?
18. Which testing methodes can you mention to test the quality of steel?
19. Which types of welding seams are used, depending on the thickness of the plates?
20. Mention 7 steel building profiles.
21. Mention 4 welding methods.
22. There are two main methods to protect the steel during welding. Discribe both metods.
23. Under what circumstances inert gas cannot be used to protect the weld puddle during welding?
24. What is the length between perpendiculars? (Lpp)
25. What is the length overall? (Loa.)
26. What is the waterline-length?
27. What is the fore-perpendicular? (Fpp)
28. What is the aft-perpendicular? (App)
29. What is the draught-fore and aft?
30. What is the sheer?
31. What is the meaning of the abbreviation GT and what information does it provide?
32. What is the meaning of the abbreviation NT and what information does it provide?
33. What is deadweight and what is cargocapacity?
34. What is the ship’s trim?
35. What is the meaning of the expression: trimmed by the bow?
36. What is the meaning of the expression: trimmed by the stem?
37. The ship is on an even keel.What does that mean?
38. What is camber?
39. What is deadrise or rise of floor?
40. What is the bilge radius?
41. What is the depth?
42. At what location the depth is measured?
43. What is the moulded beam?
44. What is the beam or breath overall (extreme)?
45. What is displacement in m3 and what is displacement in tonnes?
46. A ship is laying in seawater (s. g. 1,025 ton/m3) and has a displacement in tonnes of 1025. If the ship sails to fresh water, will the displacement increase, decrease or stay the same value?
47. What is the airdraught of a ship?
48. Will the airdraught increase or decrease when the ship will be ballasted?
49. What is the difference between Carene and dispacement in m3
50. What is the light ship (weight) in tonnes?
51. Why is, at a given draugt, the dead weight a fixed number and the cargo capacity a variable one?
Reply
#2
my personal answers to the questions of chapter 1 ... feel free to give feedback & critics  Smile

1. Mention 4 reasons to design a ship with a good streamline.

- to reduce resistance
- to avoid vibrations (for reducing stresses within the ship)
- good ship movements (through water)
- "release" of the water (by shape of stern)
- influence on stability
- seaworthyness
- efficiency = reducing fuel costs

2. What is the difference between the linesplan of an orca and that of a ship?

The "Orca" has the ideal linesplan.


3. Mention 3 reasons why steel replaced wood as a shipbuilding material. (Rec.: From 1880 until 1905 iron was used and later steel.)

- less weight / dimensions compared to wood (Rec.: Big wooden barges had backwards constructed stern to get stronger vessel. From Fore to aft a bilge strake is constructed, which is a bend between bottom and side hull. Building iron barges the bilge strakes disappeared.)
- More easy to form curves and shapes (Rec.: The iron or stell construction became more curved towards the curved bottom, also at the stern.)
- more easy to build (e.g. using specific types of welding as main process, related to the thickness of the plates. Rivets are not used anymore, only for restoration of "old ships".)

4. Which construction method is called clinker-built?

The Skeleton method, in which a keel and frames are used and hull plates are attached to the frames.

Clinker-built: Hull plates overlap.


5. Which construction method is called carvel-built?

The Skeleton method, in which a keel and frames are used and hull plates are attached to the frames.

Carvel-built: Hull plates are connected in a row next to each other.


6. What is the difference between the skeleton-building and the scale-building method of ships?

Skeleton method: a keel and frame are used and hull plates are attached to the frames.

Scale method: Square-rigged vessels were designed mostly by a master builder or the foreman of the shipyard, not by a naval architect.

The master builder did not follow an architect's plans, but created a half model of a the ship from which to work, often on a scale of 3/8"" to the foot, but not always. This model was carved out of many horizontal layers of wood pegged together to form a block. These layers provided the builder with the shape of the vessel at various depths or was measured, from its flat side to its curved edge, at equidistant intervals running the length of the model. This vertical center line running measurements represented the distance on the actual vessel from the parallel with the keel, to the insides of the vessel's frames. When scaled up to full size and potted on the floor of a shed or "mould loft", they created a pattern from which the shape and measurements of each of the vessel's frames could be taken.

The pre-mathematical, geometrical concept of using plans at reduced scale in three orthogonal views - transverse, horizontal and longitudinal - wa not yet used by the
(French) shipbuilders, not even when some experimental tests had been made during the years 1680-1685.

One of the oldest tests is given by a plan of a fluit for galleys dated to the years 1684-1685. The author of this graphical document is the Mediterranean master shipbuilder François Coulomb.

7. What is TEU?

Twenty-foot equivalent unit = a 20-foot container

8. What is a Feeder?

(Container) Feeder .... small container ships specialized in transport of containers from main ports to smaller ports (sometimes to inland ports).

9. What is a VLCC?

Tankers are devided in 3 classes:
- Crude Carrier
- VLCC = Very Large Crude Carrier - 200-300,000 dwt (deadweight)
- ULCC = Ultra Large Crude Carrier >300,000 dwt

Tankers are ships used to carry liquid cargos in tanks, e.g. crude oil, refined petrochemical products, cemhicals, edible products or liquid gas.

10. Mention 3 functions of a supplier.

Supply vessels ... are used in ""offshore industries"".

- supplying offshore platforms
- anchor handling tug
- diving support vessel
- standby vessel

11. What is a squarebox-ship?   

"Modern ships are all double hull ships for safety reasons and more and more ""box shaped"" for efficient loading and discharging.

V-shaped frames in the fore part are the best compromise between stability, seaworthiness and fuel consumption. At larger draughts, stabilty and buoyancy increse.

The sheer line at the higher part of the fore ship will act as a breakwater and it makes the construction of a strong box shape fore part possible.

12. What is a bulkcarrier?   

"Bulk carriers ... specially designed ships that carry loose cargo in bulk - in separated holds.

Bulk carriers have large upper and lower ballast tanks to shape the hold for automatic grain stowage and to eliminate free surface (ullage) ... and to give the empty vessel sufficient draught and greater stability in transit.

Some bulk carriers can also function as tankers to sail more efficient. Ore bulk carriers have a special design (see page 9). Combination carriers are called ""Ore Bulk Oil"" (OBO) carrier.

13. What is a Ro-Ro ship?

Ro-Ro ship = Roll-on/Roll-off ships facilitate the transport of mobile cargo and have continuous decks over the entire length of the ship. The ro-ro ship is different from lo-lo (lift on-lift off) ship that uses a crane to load the cargo.

Loading and discharging proceeds via (built in) ramps at the stern and/or at the bow.

RoRo ships have continuous decks over the entire length of the ship. For safety reasons transverse divions doors, dividng the deck into compartments, are needed. (Rec.: The danger of ""Free surface water"" will be eliminated this way.

14. Make a sketch of the general arrangement of a cargoship.

Ship arrangement .... drawing (see figure 5 on page 10).

15. Which construction materials can be used for the ship’s hull?

wood, ferro metals (e.g. iron, steel), non-metals (e.g. copper, bronze), composite, aluminium

16. What is the difference between iron and steel?

Iron and steel both belong to the ""ferro metals"". Pure iron is not used anymore, it is mixed with carbon (as so called ""alloy""). Iron with less than 2% carbon is called ""steel"". Iron with more than 2% carbon is called "cast iron".

By adding carbon ""malleability"" is decreasing and ""casting ability"" is increasing.

17. Which element is added to the steel-alloy to improve the tensile strength of the material?

Manganese, Mn.(page 11)

18. Which testing methodes can you mention to test the quality of steel?

- yield test
- bending test
- hardness test
- charpy impact test"

19. Which types of welding seams are used, depending on the thickness of the plates?

- open V shape ... for 5-22 mm plates
- X shape ... for very thick plates
- K shape ... welding two perpendicular plates

20. Mention 7 steel building profiles.

Profiles are characterized by the shape of the cross-section. Normal length of a profile is 6 meter. Different steel bars (see figure 6 on page 11 and figure 7 on page 12):

- flat
- (half / quarter) round
- square
- half oval
- angel
- wide flange beam / standard (I) beam
- T bar
- Zeta bar
- channel (U)

21. Mention 4 welding methods.

- Oxyacetylene welding
- Gas metal arc (GMAW) ... commonly termed MIG (metal, inert gas)
- Gas tungsten arc (GTAW) ... also known as TIG (tungsten, inert gas)
- Shielded metal arc (SMAW)

22. There are two main methods to protect the steel during welding. Discribe both metods.

1. Inert shielding gas (Argon or Helium) to protect the weld area from atmospheric contamination by inert shielding gas, e.g. GMAW ... spray an argon-based shielding gas or a mix of argon and carbon dioxide (CO2) over the weld puddle to proect it from the outside world.

2. Electrode with a flux around it (see SMAW) as protectant for the puddle. Slag protects the weld puddle from the outside world.


23. Under what circumstances inert gas cannot be used to protect the weld puddle during welding?

Regularly welding requiers a constant temperature. Welding with "inert gas" can be used, when main sections are built in a shed. Thick plates needed to be preheated to avoid deformation during welding on thin plates.


24. What is the length between perpendiculars? (Lpp)

Length between perpendiculars = Lpp

Length from aft perpendicular to fore perpendicular (or: from fore perpendicular to the centre of the rudder stock, if the constructin waterline is not crossing the stern).

This length is used by the Classification Society.

25. What is the length overall? (Loa.)

length overall = Loa

real length = length of the ship between extremities.

26. What is the waterline-length?

waterline-length = Lcwl

Length from fore perpendicular to aft perpendicular on the construction water line

27. What is the fore-perpendicular? (Fpp)

fore-perpendicular = Fpp

... an imaginary line perpendicular to the construction water line. The Fpp crosses the waterline and the bow.

28. What is the aft-perpendicular? (App)

aft-perpendicular = App

... an imaginary line perpendicular to the construction water line. The App crosses the waterline and the stern. (Rec.: If the waterline is not crossing the stern, the App aligns with the centre line of the rudder stock.)

29. What is the draught-fore and aft?

Draught is the height between baseline and the actual water line = maximum depth underwater, incl. shell plating.

30. What is the sheer?

Sheer = measure of longitudinal main deck curvature.

The sheer forward is (usually) twice that of sheer aft.

It increases the rise of the sheer forward and aft and builds volume into the hull, an din turn increases it buoyancy fowrad and aft, thereby keeping the ends from diving into an oncoming wave slowing the ship.

31. What is the meaning of the abbreviation GT and what information does it provide?

GT = Gross Tonnage.

GT is calculated using a formula that takes into account the ship's volume below main deck and the enclosed spaces above main deck. This volume is multiplied by a coefficient. The result is a non-dimensional number.

The GT is mainly used to calculate pilot and harbour fees. It is also used to calculate minimum crewing of the ship.

(Rec.: Gross Tonnage (TG), Nett Tonnage (NT) or Deadweight are terms which do not express the size of the ship. These are terms to express their loading capacity and are internationally accepted.)

32. What is the meaning of the abbreviation NT and what information does it provide?

NT = NETT Tonnage.

NT is a non-dimensional number - same as GT - that describes the volume of the cargo space. NT may not be less than 30% of GT.

(Rec.: Gross Tonnage (TG), Nett Tonnage (NT) or Deadweight are terms which do not express the size of the ship. These are terms to express their loading capacity and are internationally accepted.)


33. What is deadweight and what is cargocapacity?

Deadweight (ton) is the weight a ship can load to take her from her lightship draught to her summer load line draught.

The formula: Deadweight = Design displacement - Light ship weight.

Lightship weight in ton is the weight of the ship including regular inventory like anchors, luboil, spare part of ER (Engine Room), paint etc. but without cargo, fuel and crew.

(Rec.: Gross Tonnage (TG), Nett Tonnage (NT) or Deadweight are terms which do not express the size of the ship. These are terms to express their loading capacity and are internationally accepted.) "

34. What is the ship’s trim?

Trim = Difference bewtween th edraft at the fore perpendicular (Fpp) and the draft at the aft perpendicular (App).

35. What is the meaning of the expression: trimmed by the bow?

Trim is defined as the difference between the draft forward (bow) and the draft aft (stern). Draft is the depth of the hull below the water.

If the aft draft is greater, the vessel is described as being trimmed by the stern, if the forward draft is greater, she is trimmed by the bow.

Trimmed by the stern is called negative (–), trimmed by the bow positive (+).

36. What is the meaning of the expression: trimmed by the stem?

Trim is defined as the difference between the draft forward (bow) and the draft aft (stern). Draft is the depth of the hull below the water.

If the aft draft is greater, the vessel is described as being trimmed by the stern, if the forward draft is greater, she is trimmed by the bow.

Trimmed by the stern is called negative (–), trimmed by the bow positive (+)."

37. The ship is on an even keel.What does that mean?

Every vessel has a designed seagoing trim where a baseline is drawn parallel to the designed summer load waterline.

On a merchant ship, the designed loaded sea going trim is even keel (drafts forward and aft are the same and the keel corresponds to the baseline).

(Rec.: Smaller vessels are more likely to have rake in the keel (sloping from forward to aft) so that when floating at the designed sea going trim, the after draft will usually be greater than the forward draft.)"

38. What is camber?

camber = a measure of lateral main deck curvature in naval architecture.

The curve is applied to a deck transversely, measured as the height of deck at centreline above the height of deck at side.

The practice of adding camber to a ship's deck originated in the era of small sailing ships.

39. What is deadrise or rise of floor?

Deadrise is measured two ways, by linear measurement like inches or centimeters and by expressing it as an angle.

here: deadrise = amount of angle that forms between the boat bottom and a horizontal plane on either side of center keel. The deadrise  angle is the least (meaning flattest) at the transom and gradually increases (more vee) as the bottom goes forward and then increases at a greater rate at the bow.

40. What is the bilge radius?

Bilge radius = Radius of the plating joining the side shell to the bottom shell. It is measured at midships.

41. What is the depth?

Depth (D) = height from baseline to uppermost continuous deck at the side, inside plating.

42. At what location the depth is measured?

Depth (D) = height from baseline to uppermost continuous deck at the side, inside plating.

43. What is the moulded beam?   

Moulded beam (B) = width measured at inside of the shell plating.


44. What is the beam or breath overall (extreme)?

Beam or Breadth (Boa) = width of hull measured outside of the shell plating from starboard to port side at the midship section.

45. What is displacement in m3 and what is displacement in tonnes?

1. Displacement (m3) = Volume of the part of the ship below the water line including shell plating, propeller and rudder.

2. Δ Displacement (ton) = Total mass of the ship including "everything" ~ weight of the volume of water displaced by the ship.

Formula: Δ = V x ρ (rho  = density of water)"

46. A ship is laying in seawater (s. g. 1,025 ton/m3) and has a displacement in tonnes of 1025. If the ship sails to fresh water, will the displacement increase, decrease or stay the same value?

Displacement stays constant: Δ sw = Δ fw, but the volume and draft will increase.

Δ sw = V1 x ρ sw  => 1,025 t = V1 x 1.025 t/m3 => V1 = 1,000 m3
Δ fw = V2 x ρ fw  => 1,025 t = V2 x 1.000 t /m3 => V2 = 1,025 m3

47. What is the airdraught of a ship?

Air draught = Distance between actual waterline and the highest point of the ship.

48. Will the airdraught increase or decrease when the ship will be ballasted?   

If the ship is out of ballast, the "air draught" will increase, as the water line will be lower.

49. What is the difference between Carene and dispacement in m3 ?

Carene (m3) = part of the hull which is under the water line, being calculated by using the lines plan. (Rec.: The Lines plan is made without calculating the thickness of the shell plating.)

Displacement (m3) = Volume of the part of the ship below the water line including shell plating, propeller and rudder.

Carene is not exactly the real content as it is calculated without the thickness of the shall plating. Calculating with 3/4 % more will result in the displacement, used for stability calculations.

50. What is the light ship (weight) in tonnes?

Lightship weight in ton is the weight of the ship including regular inventory like anchors, luboil, spare part of ER (Engine Room), paint etc. but without cargo, fuel and crew.

51. Why is, at a given draugt, the dead weight a fixed number and the cargo capacity a variable one?

Deadweight (ton) is without cargo, depending on the light ship weight. It is the weight a ship can load to take her from her lightship draught to her summer load line draught.

The formula: Deadweight = Design displacement - Light ship weight.

(Rec.: Lightship weight in ton is the weight of the ship including regular inventory like anchors, luboil, spare part of ER (Engine Room), paint etc. but without cargo, fuel and crew.)

Cargo Capacity = total weight of the cargo a ship is designed to carry. It depends on the ship's maximum allowable immersion at the relevant season and the ballast, fuel and provisions -> The cargo capacity will vary.
+++


Attached Files
.pdf   Question Catalogue 2017-2018_SHIBU with complete answers - chapter 1.pdf (Size: 91.84 KB / Downloads: 6)
Reply
#3
Chapter 2 ... question catalogue

1. Mention the 4 basic drawings of a ship?
2. Which main data (5) are displayed on a midshipsection-drawing?
3. What is the general arrangement plan and which views (3) are shown here?
4. What information is displayed on the views mentioned in question 3?
5. Which main particulars are can be found on the general arrangementplan?
6. What subjects and information can be found on the general construction plan? Mention at least 6 items.
7. What information is displayed on the safety plan?
8. What 3 important items are displayed on the dock plan?
9. What is a linesplan?
10. What are ordinates?
11. What are waterlines?
12. What are verticals?
13. Wat zijn sentlines”?
14. Mention 4 important ship’s drawings that have to be on board at all times.
15. What is a block coéffici'ent?
16. Has a ship with a large blockcoéfficiént a larger or a smaller cargocapacity than a ship with a small blockcoéffici'ent? Please explain.
17. What is a mid section coéfficiént?
18. What is a water plane coéfficiént?
19. Make a calculation of the increase of dispacement in m3 , using L , B and the waterplanecoéffici'ent when the draught increases with 1 cm.
20. What is in a ship’s construction the meaning of “the extreme fiber(distance)”?
21. What is the neutral axis of the ship and what are the stresslevels in this area??
22. Mention several static forces working on the ship (3)
23. Mention several dynamic forces working on the ship (3)
24. What is a SWBM?
25. What is a WBM?
26.1 What is “hogging”?
26.2 What is “sagging” ?
27. What is torsion stress and and what can be the causes?
28. What causes longitudinal stresses?
29. What causes transversal stresses?
30. What is racking and which construction parts are designed to withstand these loads?
31. What is panting and which 4 construction parts are designed to withstand these loads?
32. What is pounding and which 3 construction parts are designed to withstand these loads?
33. Mention 3 local loads that can work on the ship’s hull.
34. Which construction elements are positioned longitudinal in a longitudinal framing system?
35. Which construction elements are positioned transversal in a transversal framing system?
36. What is the responsability of a classification society and which tasks are carried out by this organisation?
37. Mention 4 classification societies.
38. What does the abbreviation IL en T mean and what is the responsability of this organisation?
39. Mention 2 drawings that have to be submitted to ILenT.
40. Mention 2 drawings that have to be submitted to the classification society.
41. What certificate is issued by the classification society upon completion of the ship’s construction?
42. Which 3 certificates are issued by ILenT upon completion of the ship’s construction?
43. What is a “condition of class”?
44. What is the freeboard?
45. What is the deckline?
46. What is the Plimsoll mark or loadline and what can you tell about its origin?
47. Mention at least 4 loadlinemarks.
48. Make a sketch of a Plimsollmark, including the deckline and at least 2 other loadline marks.
49. Why must the loaodlinemarks be welded to the ship’s hull?
Reply
#4
my personal answers for question catalogue of chapter 2. Tricky ...   Undecided feel free to give feedback and correct.

1. Mention the 4 basic drawings of a ship?

- General arrangement plan
[Image: cougar.jpg]

- Midship section plan
[Image: hull6-768x522.png]
- construction/scantling plan

Scantling is a nautical term which refers to all dimensions given for a ship's timbers, planks etc. Timber dimensions are always distinguished by the terms "sided" and "moulded" rather than in non-nautical terms such as: width, thickness, or depth. (source: Archaeology - British Columbia Shipwreck Recording Guide)
[Image: scantling_3.jpg]   [Image: Runabout-Boat-Plans-3.jpg]

- Lines plan (Rec.: right side is the "body plan" as part of the lines plan)
[Image: hull5.png] [Image: hull4-768x354.png]

2. Which main data (5) are displayed on a midshipsection-drawing?

- principal dimensions
- Classification information
- Engine power and speed
- Equipment number
- Cargo gear and lifting capacity
- Stack loads of tank top and decks
- Maximum longitudinal bending moment

3. What is the general arrangement plan and which views (3) are shown here?

GAP shows the divisions and arrangement of the ship as a map of the most important decks.

Cross section and side view of the ship is displayed.

4. What information is displayed on the views mentioned in question 3?

- data of the principal dimensions
- Volume of holds, tonnage, class deadweight …

5. Which main particulars are can be found on the general arrangement plan?

A copy of the GAP is always displayed in conspicuous locations accessible and frequented by the ship’s crew. The general layout is displayed through a side profile, mid-ship section and arial view of decks on board a ship. The general arrangement plan will familiarize the seaman with the Following information:

- number of hatches on the ship
- number of cargo compartments on the ship.
- location of various double bottom tanks, topside tanks, peak tanks, cofferdams etc.
- number and location of fuel oil tanks.
- location of various decks, engine room, saloon and store rooms etc.
- salient features of lift gear
- location of emergency machinery i.e steering gear, generator, fire pump etc.
- location of crew and master’s accommodation.
- location of navigation bridge, chart room, monkey island etc.
- salient of deck fittings, lifting gear, deck machinery, gangway etc.

(Source: Naval Architecture)


- division and arrangement of the ship (as a map of the most important decks)
- cross-section of the ship
- side-view of the ship
- data of the principal dimensions
- volume of the holds, tonnage, class, deadweight etc. ...

(Rec.: The general arrangement plan is used to make a safety plan.)

6. What subjects and information can be found on the general construction plan? Mention at least 6 items.

- Longitudinal centre line sections
- Most important decks and tank top
- Construction drawings with dimensions from bow and stern together with panting beams

... plus tender with complete descriptionby the owner, e.g. specific type, main dimensions, equipment and necessary materials

7. What information is displayed on the safety plan?

safety plan = general arrangement plan

… with all safety information on each deck (e.g. life rafts, life boats, escape routes, fire-hosed, extinguishers etc. …)

8. What 3 important items are displayed on the dock plan?

- the plan shows, where the ship can be supported by the keel blocks
- the place of the longitudinal and transverse bulkheads are displayed
- position of shell openings, drain plugs, keel, floor plates etc. ...

... also see chapter 4.5 Dry Docking, page 78

9. What is a linesplan?

It shows the shape of the ship, from all directions possible (in 2D and in 3D).

The main drawings are:
- Water Lines
- Verticals
- Ordinates (Sent lines)

10. What are ordinates?

Ordinates or Sent lines are vertical cross-sections in transverse direction and evenly spaced.  The ship is divided into 20 ordinates from App (Aft perpendicular) to Fpp (Fore perpendicular).

Half of the section is shown because the hull is symmetric. (Rec.: On the right side of the drawing is shown the fore ship, on the left side the aft ship)

!! Ordinates are no frames !!

11. What are waterlines?

WLs are horizontal sections of the hull.

From base line at every meter draught a line is given. Mostly also the scanting line.

(Rec.: Scantlings are the dimensions of all structural parts used in building a vessel (e.g. frames, girders, platings).

Half of the water-line is shown as the hull is symmetrical. The vertical lines are used for the buttock lines (which represent the traces of vertical sections parallel to the vessel's longitudinal center plane, also called bow lines when in the forebody and buttock lines when in the afterbody).

12. What are verticals?

Vertical Lines (or Buttock lines) are drawings with lingitudinal lines, 1m in between, parallel to the plane of symmetry of the ship. The lines are projected 2D in a drawing.

Vertical Lines (or Buttock lines) are drawings mostly combined with the ordinates (see question 10).

13. Wat zijn sentlines”?

... see answer No. 10

14. Mention 4 important ship’s drawings that have to be on board at all times.

It is compulsory (IMO) to keep all ship plans in the ship office and on board.

The 4 basic ship drawings are:
- General arrangement plan
- midship section
- construction / scantling plan
- lines plans (3 main drawings)

… and some more:
- docking plan + shell expansion
- piping plan
- safety plan
- capacity plan

15. What is a block coéfficiént?

Ratio of volume of underwater body and rectangular block bounded by Lwl (Length of Waterline), T (draft) and B (moulded breadth).

16. Has a ship with a large block coéfficiént a larger or a smaller cargocapacity than a ship with a small block coéfficiént? Please explain.

Large ratio = large cargo capacity, see formula: Volume of underwater body / (Lwl x T x B)

17. What is a mid section coéfficiént?

Mid (ship) section coéfficiént = ratio of area of the midship section and area bounded by T (draft) and B (moulded breadth)

18. What is a water plane coéfficiént?

Water plane coéfficiént = ratio of area of water plane and rectangular plane bounded by B (moulded breath) and Lwl (Length of Water line)

19. Make a calculation of the increase of dispacement in m3 , using L , B and the waterplanecoéffici'ent when the draught increases with 1 cm.

If the waterplane is for example

L=20, B=6
=> area is 120 m2, draught increases with 0,01 m
=> displacement is 1,2 m3 (20x6x0,01)

20. What is in a ship’s construction the meaning of “the extreme fiber(distance)”?

top layer of the box spar and bottom layer (page 21 top)

21. What is the neutral axis of the ship and what are the stresslevels in this area?

The middle part of the ship is the neutral axis.

It is bending without deflection. There is not a lot of stress there.

22. Mention several static forces working on the ship (3)

static forces ...
- pressure of the engine on the bottom of the ship
- cargo - weight of the ship (→ hydrostatic pressure / → Dry Docking stresses)

23. Mention several dynamic forces working on the ship (3)

dynamic forces ...
- forces of waves/swell
- forces of vibrations
- forces of wind

24. What is a SWBM?

SWBM = Still Water Bending Moment …
bending by extreme longitudinal stresses due to static forces

25. What is a WBM?

WBM = Wave Bending Moment …
bending due to dynamic forces

26.1 What is “hogging”?

Vertical deflection of a ship's hull, in longitudinal direction.

The hull is bent UPWARDS amidships (as a result of cargo distribution and/or the way the ship is supported by a wave CREST)

26.2 What is “sagging” ?

Opposite to “Hogging” deflection of a ship's hull, in longitudinal direction.

The hull is bent DOWNWARDS amidships (as a result of cargo distribution and/or the way the ship is supported by a wave TROUGH)

27. What is torsion stress and and what can be the causes?

Torsion stress can occur in large open cargo hold container ships.

These torsion loads cause high stress levels at the corners of the open hatches (weak areas).

To reduce the stress from torsion, these corners are rounded of parabolic. The torsion stress is reduced by shearing frames.

28. What causes longitudinal stresses?

- static forces, see SWBM (question 24)
- dynamic forces, see WBM (qustion 25)
- see also hogging and sagging (question 26)

29. What causes transversal stresses?

racking (due to rolling or wrong loading) and the effects of water pressure

30. What is racking and which construction parts are designed to withstand these loads?

When a ship is rolling in seaway or struck by beam waves, the ship's structure is liable to distort in a transverse direction.

The stress mainly affects the corners of the ship. Transverse bulkheads, frames and web frames provide great strength to resist racking.

31. What is panting and which 4 construction parts are designed to withstand these loads?

Panting stresses … in fore-ship during pitching / slamming = in heavy seas constantly increase and decrease of volume of fore-ship.

Constantly changing water (= hydrodynamic) pressure increases stress in hull and frames.

Panting beams (in transverse direction) and stringers against the hull, brackets and bulkheads can resist the stress.

More frames and floors are inserted at smaller intervals to prevent the fore-ship bottom area from damage.

32. What is pounding and which 3 construction parts are designed to withstand these loads?

… when pitching is so heavy that the entire bow rises above the water survace.

Dynamic forces on bottom plates are significant.

Forward bottom structure is strengthened (for between 25-30% of the length). Plate floors are fitted on each frame station (transverse framing) or alternate frame stations (longitudinal framing) with intercostal side girders (not more than 2.2m apart).

33. Mention 3 local loads that can work on the ship’s hull.

- panting stresses
– pounding
– vibration stresses

34. Which construction elements are positioned longitudinal in a longitudinal framing system?

Shell plating, deck and bottom plating (fore and aft); bulkheads for transverse stiffening.

35. Which construction elements are positioned transversal in a transversal framing system?

Web frames, stringers, side shell frames and deck girders; vertical keel and side girders for necessary longitudinal stiffening.

36. What is the responsability of a classification society and which tasks are carried out by this organisation?

Supervising legal rules in accordance to safety and seaworthiness of ships.

Main Tasks:
- supervision of ship building process
- approving construction drawings
- inspection of actual construction, all mashinery, rigging and installations

37. Mention 4 classification societies.

- RH - Register Holland (for commercial sailing vessels up to 500 GT and max. 36 passengers)
- LR – Lloyds Register (London)
- GL – Germanischer Lloyd (Berlin)
- BV – Bureau Veritas (Paris)
- ABS – American Bureau of Shipping (N.Y.)
- DNV – Det Norske Veritas (Oslo)
- CSS – China Cliassification Society (CCS)

38. What does the abbreviation IL en T mean and what is the responsability of this organisation?

IlenT = Inspectie Leefomgeving en Transport (= Human Environment and Transport Inspectorate)

Supervising legal rules in accordance to safety and seaworthiness of ships.

39. Mention 2 drawings that have to be submitted to ILenT.

Ships fully covered by all International Conventions: Safety plan approved by one of the recognised classification societies (single copy).

Ships that are not covered by (one of) the International Conventions or parts thereof: Drawings related to the parts not covered by the International Conventions in accordance with the existing list (in triplicate), see http://www.ilent.nl, drawings approval.

40. Mention 2 drawings that have to be submitted to the classification society.

Register Holland classified (sailing) ships:
- Safety plan approved by one of the recognised classification society (single copy) and
- all drawings related to the radio installations (in triplicate)

The Human Environment and Transport Inspectorate (ILenT) reserves the right to request drawings and documents from the classification society in order to maintain supervision of the plan approval activities performed by the classification society on behalf of the Inspectorate.

41. What certificate is issued by the classification society upon completion of the ship’s construction?

Certificate of class (page 23)

42. Which 3 certificates are issued by ILenT upon completion of the ship’s construction?

3 certificates issued by IlenT:


- safety certifcate
- int. tonnage certificate
- Intern. Loadline certificate

(page 23)

43. What is a “condition of class”?

“condition of class” = specific certificate, known as “Conditional Certificate”.

If a ship has damage after an accident the “Certificate of Class” is no longer valid. After repair and approval of the surveyor of the Classification Societa a “temporary certificate” will be issued until the next official survey.

44. What is the freeboard?

Freeboard (of commercial vessels) is between lowest point of the uppermost continuous deck at side and WL (waterline).

45. What is the deckline?

Deckline is the “summer freeboard”

46. What is the Plimsoll mark or loadline and what can you tell about its origin?

a specific marking, the “International Load line” (or water line positioned amidships). It indicates the draft of the ship and the legal limit to which a ship may be loaded for specific water types and temperatures in order to safely maintain buyoancy.

British pariliament member Samuel Plimsoll was the initiator after an increased loss of ships due to overloading in the early 19th century. In 1876 the UK made the load line mark compulsory, known as Plimsoll Mark.

47. Mention at least 4 loadline marks.

Tropical Fresh water (TF), Fresh Water (F), Tropical Salt Water (T), Summer Temperature Saltwater (S), Winter Temperature Saltwater (W), WNO (Winter North Atlantic)

48. Make a sketch of a Plimsollmark, including the deckline and at least 2 other loadline marks.

... answer see page 25

49. Why must the loaodlinemarks be welded to the ship’s hull?

Freeboard/Load line are described in the Load Line Certificate which exists for each ship and which must be compulsory on board of a ship. Plimsol marks are permanently, therefore welded to avoid overpainting (by accident) and protect against manipulation.
+++


Attached Files
.pdf   Question Catalogue 2017-2018_SHIBU with complete answers - chapter 2.pdf (Size: 87.9 KB / Downloads: 9)
Reply
#5
Chapter 3 ... question catalogue


1. Mention 3 functions of the shellplating of the hull.
2. What is a strake?
3. How is the shellplating of the hull supported?
4. What is a shell expansion plan?
5. What information can be found on a shell expansion plan?
6. The shellplating amidships is thicker than at the ships fore and aft end. Why?
7. How are platestakes indicated?
8. What is a gusset plate?
9. What is a lost strake?
10. What is a seam, what is a butt?
11. What arrangements ( active and passive) can be used to reduce drift and rolling of the ship?
12. What is the function of a bilgekeel and how is the connection to the ship’s shell? (drawing)
13. Why is the bilgekeel welded on a backing strip?
14. What is a webframe?
15. What is a stringer?
16. What is a carling?
17. What is a floor?
18. Mention 4 lokations in the ship’ sshellplating where thicker plates made from high quality steel are used.
19. Why is it not allowed to use doubling plates on seagoing vessels?
20. Mention 6 functions of a double bottom.
21. For which 3 types of ships a double bottom is compulsory?
22. Which 4 loads are absorbed efficiently by the double bottom?
23. Which 5 components of the double bottom reinforce the longitudinal strength of the ship?
24. Make a sketch of a double bottom construction in a longitudinal framed ship and mention at least 7 components.
25. Make a sketch of a double bottom construction in a transverse framed ship and mention at least 7 components.
26. Mention 4 types of floors, make a sketch of each type and mention at least 5 components of each type of floor.
27. Mention 3 advantages of a longitudinal framed construction.
28. What is a centre girder?
29. What is a1. Mention 3 functions of the shellplating of the hull.
30. What is a cofferdam?
31. What is a ductkeel?
32. What are the functions of the enginefoundation and how can it be constructed?
33. Which components on the enginefoundation are used for alignment of the engine and propellorshaft?
34. What technical application is nowadays used to replace the steel filling pieces after alignment?
35. Which 4 constructioncomponents are used to support the side hull?
36. Mention 4 specific construction components to absorb longitudinal stresses?
37. Mention 4 specific construction components to absorb transversal stresses?
38. What is a deckstringer?
39. Mention 4 types of decks?
40. What is a roach plate?
41. Mention 3 spaces in the foreship.
42. Mention 2 qualities of a well constructed chainlocker.
43. Explain the effect of bulbous bow and when will the maximum efficiency be achieved?
44. Why are sometimes the ship’s bilges filled with concrete?
45. Mention 5 components of the pantingarrangement.
46. Mention 3 components of the poundingarrangement.
47. Which area of the ship is additionally strengthened for pounding?
48. Mention 3 constructiontypes of the stempost.
49. Why are openings in the shell rounded off?
50. Make a sketch of a stern frame and mention at least 5 components.
51. Mention 4 ruddertypes and make sketch of each type.
52. Mention an advantage of the balancerudder.
53. Mention 2 advantages of an Oertzrudder.
54. Make a sketch of a steering gear with 2 hydraulic rams and mention 4 components.
55. Mention 4 reasons why a vessel is subdivided into several compartments by bulkheads.
56. Mention the name of 5 different types of bulkheads.
57. Why is the exact lokation of the collision bulkhead important?
58. How long must a A-3O bulkhead be flame and smoke resistant?
59. What does the number 30 mean in an A-30 bulkhead?
60. What material is used for the construction of an A-15 bulkhead?
61. What are the properties of the constructionmaterial of a B-15 bulkhead?
62. What regulations (6) do apply for a collision bulkhead?
63. Which are the 4 major parts of the bilgearrangement?
64. What are the 4 possible reasons of the accumulation of unwanted water in the bilge?
65. Make a simple sketch of a bilgediagram, showing the main components.
66. What are the main differences between a bilge-and a ballastsystem?
67. What are the main differences between a bilge-and a ballastmanifold?
68. Mention 4 possible functions of a general service pump?
Reply
#6
my personal answers to Chapter 3 ... 


1. Mention 3 functions of the shell plating of the hull. "3 functions of the shell plating of the hull (supported by longitudinal and transversal frames):

- keeps sea water outside of the ship
- longitudinal strengthening = withstanding bending forces
- loading + swell ... withstanding water pressure and sheering forces"

2. What is a strake?
constructed frame
Definition of strake:Shell plates are arranged in strakes = continuous line of planking (of plates) from stem to stern of a ship.

(see figure 18 "plate strakes"on page 27)

A strake which is not continued due to the shape differences (narrowing of the hull) is called a ""lost strake.""

Two strakes will join and the joining plate is called a ""gusset plate"".

(see figure 19 "gusset plate" on page 27)

3. How is the shell plating of the hull supported?

A shell plating is being supported by "longitudinal" and "transversal" frames.

4. What is a shell expansion plan?

Hull datas are displayed in the shell expansion plan.

5. What information can be found on a shell expansion plan?

Hull datas are displayed in the shell expansion plan. E.g.

- distance between two frames (longitudinal and transversal) depending on the load on the plating
- extra reinforcements of the fore ship due to panting and pounding stresses.
- different loads -> different thickness and quality of the (welded steel) plates.


6. The shell plating amidships is thicker than at the ships fore and aft end. Why?

Amidships where the bending force is the strongest the shell plating construction should be thicker.

7. How are plate stakes indicated?

The numbering of the plates is done longitudinal.

The 1st strake alongside the keel is called the A strake (or garboard strake) on the shell expansion.

8. What is a gusset plate?

If two strakes will join, the joining plate is called a "gusset plate".

(see figure 19 "gusset plate" on page 27)

9. What is a lost strake?

A strake which is not continued due to the shape differences (narrowing of the hull) is called a "lost strake."

10. What is a seam, what is a butt?

The longitudinal welding between two plates is the seam, and the short welding is a butt.

Some basics about Seam and butt welding ...

Butt welding is a welding technique used to connect parts which are nearly parallel and don't overlap. It can be used to run a processing machine continuously, as opposed to having to restart such machine with a new supply of metals. Butt-welding is an economical and reliable way of joining without using additional components.

Usually, a butt-welding joint is made by gradually heating up the two weld ends with a weld plate and then joining them under a specific pressure. This process is very suitable for prefabrication and producing special fittings.

Seam Weld is also known as "continuous weld". Seam welding is a continuous weld along a joint. Seam welds can be in the form of a fillet weld and a butt joint weld. Seam welding is robust and is more durable because of the amount of surface area that is joined by a weld.

There are two common types of continuous welds:
fillet weld and butt joint weld. A fillet weld is a triangular seam weld that joins two surfaces at right angles to each other. Butt welds are generally in a lap joint, T-joint, or corner joint. This is most common amongst welding pipe or tubes to another surface.

(see figure 20 "seams and butts" on page 28)


11. What arrangements (active and passive) can be used to reduce drift and rolling of the ship?

Both, active and passive arrangements are systems to reduce drift and rolling of a ship.

- passive arrangements: bilge, keel
- active arrangements: Anti-Rolling tanks, Fin stabilizers (see figure 22 "Fin stabilizers" and figure 23 "anti-rolling tank" on page 29)

12. What is the function of a bilge keel and how is the connection to the ship’s shell? (drawing)

The function of a bilge keel: reduce roll + drift

(Rec.: Outside of the hull, near the bilge, bilge keels may be welded to reduce drift and rolling, e.g. by large and long keels or lee-boards on flat-bottomed vessels as constructions to reduce these movements = passive stability system.

Connection to the ship shell:
- welding of plates (e.g. deck stringer plate, sheer strake, bilge plate, bottom and keel plate)

(see figure 18 "plate strakes")

The flat plate keel (amidships) or "horizontal keel" is a long line of plates just below the vertical keel. The first plate being indicated is the keel plate. The first strake alongside the keel is called the A strake (or garboard strake) on the shell expansion.

13. Why is the bilge keel welded on a backing strip?

The bilge keel is welded on a backing strip, in case of damage the hull remains intact. When damaged, the bilge keel will break off, with the strip remaining attached to the shell. Without a backing strip, a crack in the bilge keel could continue into the bilge strake, which is very dangerous.

14. What is a web frame?

A web frame is a transverse support for bulkheads.

15. What is a stringer?

Stringers are horizontal stiffeners fitted along ship sides (inside).

16. What is a carling?

Carling is a short fore-end-aft timber (or steel girder) under deck to stiffen it.

17. What is a floor?

Three types of floors (for transverse strength):

(a) Solid water- or oil-tight floors (Rec.: Horse shoe plates provide proper water tightness of the longitudinal frames which are constructed through floors and contribute to the longitudinal strength and bending forces.)

(b) non water-/oil tight Solid floors reduced in weight by manholes and lightening holes.

© bracket floors (composed by a frame and inner frame, made of profiles and brackets)

(see figure 27: Different type of floors on page 34)

Floor plates contribute to transverse strength. They provide a better stiffening of the double floor construction (DB) and prevent deformation of the keel construction in the dry dock.

Bottom platings have the tendency to bend during pressure and stress forces. So longitudinal frames could tilt. To prevent tilting the frames are welded to the floors.

Solid floors are placed under the tank top where necessary for heavy cargo. In the fore ship pounding area (with highly dynamic stresses) the solid floors span is twice the transverse frame span. Under the main engine foundation, the distance equals the transverse frame span. Anywhere else the distance is three or four times the transverse frame span.

Often bracket floors are not constructed from side-to-side. They are in between solid floors, composed by a frame and inner frame. These frames are connected to the vertical keel and tank top by brackets (see figure 24: "Double bottom construction" on page 31).

18. Mention 4 locations in the ship’ shell plating where thicker plates made from high quality steel are used.

- fore- and aft (e.g. behind collision bulkhead extra strengthening and stiffening is constructed by thick hull plating, heavy and stronger bilge brackets, stringer between the frames (see figure 41: "panting arrangement aft of collision bulkhead" on page 44)

- hawse pipes

- construction water line (ice danger)

- near openings in the hull


19. Why is it not allowed to use doubling plates on seagoing vessels?

 No double plates (plate upon plate) are allowed instead using stronger plates, because ...

- measuring the hull plating thickness is impossible and
- double plating can cause lack of strength.


20. Mention 6 functions of a double bottom.

DB (Double bottom) increases the construction strength against ...

- longitudinal stress due to the bending moment
- longitudinal and transverse stress due to water pressure, cargo and rolling
- main engine (ME) vibrations, thrust from the propeller shaft and ME weight.
- stress in the bow due to pitching and pounding

21. For which 3 types of ships a double bottom is compulsory?

DB (Double bottom) is divided in different (liquid tight) compartments for storage. Bottom tanks (= deep tank) for fuel is a highly environmental risk if the bottom is damaged.

=> DB is compulsory for ...
- all new tankers for additional safety after bottom damage.
- passenger ships to protect the bilge keel and fin stabilizers.
- ships which are able to carry deck load of timber and have a specific timber load line certificate.

22. Which 4 loads are absorbed efficiently by the double bottom?

DB (Double bottom) absorbs stress caused by ...

- bending moments
- water pressure, cargo and rolling
- vibrations (main engine), thrust (propeller shaft) and weight (main engine)
- pitching and pounding (in the bow area)


23. Which 5 components of the double bottom reinforce the longitudinal strength of the ship?

Components of DB (double bottom) construction in a longitudinal framed ship:

- vertical keel (centre girder)
- horizontal keel
- centre tank top plating
- duct keel (tunnel in a double bottom construction for large ships) ~ cofferdam (= narrow, empty space between two other spaces to create a safe sub-division).
- ships with more than 4m width* need 2 side girders (and ships with more than 10m width* need 4 side girders) to increase the stiffness of the DB construction = to increase the stack loads of the tank top
--------------------
*) Register Holland Rules

24. Make a sketch of a double bottom construction in a longitudinal framed ship and mention at least 7 components.

main components of a Longitudinal framed double bottom construction:

- centre and side girder
- bottom strake
- bottom longitudinal and inner bottom longitudinal
- brackets
- Solid, solid watertight and bracket floors
- flat stiffeners (e.g. welded on side girder)

(see figure 24 "Double bottom construction: Longitudinal framed double bottom" on page 31)

25. Make a sketch of a double bottom construction in a transverse framed ship and mention at least 7 components.

main components of a transverse framed double bottom construction:

- centre and side girder
- margin plate
- bottom strake
- tank top
- bottom frame and inner bottom frame
- struts
- Solid, solid watertight and bracket floors
- flat stiffeners (e.g. welded on solid watertight floor)

(see figure 24 "Double bottom construction: transversely framed double bottom" on page 31)

26. Mention 4 types of floors, make a sketch of each type and mention at least 5 components of each type of floor.

Types of floors:

1. constructed frame (with bottom frame + inner bottom frame)
2. solid floor (on older ships)
3. solid watertight floor
4. bracket floor

floor components:

- solid floor: bottom plating, horizontal keel, center girder, side girder, tank top, bottom longitudinal, inner bottom longitudinal, drain holes and manholes, knee (to side frame)

- solid watertight floor: bottom plating, horizontal keel, center girder, side girder, tank top, bottom longitudinal, inner bottom longitudinal, horse shoe plates, knee (to side frame)

- bracket floor: bottom plating, horizontal keel, center girder, side girder, tank top, bottom longitudinal, inner bottom longitudinal, brackets (which build the bracket floor), drain holes, lightening holes, knee (to side frame)

(see figure 26 "constructed frame" on page 33 and figure 27 "different type of floors" on page 34)

27. Mention 3 advantages of a longitudinal framed construction.

3 advantages of a longitudinal framed construction:

- completely absorbing pressure during dry docking and building the keel (by the combination of vertical keel (centre girder), horizontal keel and centre tank top plating as backbone of the ship)

- better bending moment capacity (by pressure and tensile loads)

- better buckling resistance


28. What is a centre girder?

Center girder = vertical keel, a vertical plate which is placed in the bottom floor above the keel.

(see figure 24 "Double bottom construction" on page 31)

29. What is a margin plate?

In older ships the double bottom limitation to the side is the margin plate, perpendicular to the bilge strake. It forms at the lower side of the web frame a space which is called the bilge.

(see figure 26 "constructed frame" on page 33)


30. What is a cofferdam?

A tunnel = duct keel is also a cofferdam. It is a narrow, empty space between two other spaces, to create a safe subdivision. For this reason the centre girder is 100% liquid tight.

31. What is a ductkeel?

If the vertical keel is a double construction (large ships) mostly a tunnel (= duct keel) is created instead of a single centre girder.

A duct keel from the Engine Room bulkhead to the fore peak bulkhead is called a "pipe tunnel" when used for ballast and bilge piping.

(see figure 25 "Duct keel" on page 32)

32. What are the functions of the engine foundation and how can it be constructed?

Function of the engine foundation:

- it is part of the bottom construction
- it transfers the weight of the engine and resulting stresses onto the ship's structure
- it induces the vibrations (engine, propeller shaft) and resulting stresses onto the ship's structure
- it keeps the engine in place when the ship is rolling and/or pitching (dynamic forces)

Constructions:
(a) Flat foundation as part of the double floor (DB) with a foundation plate = stronger and ticker strake of the tank top placed upon two specific side girders (engine girders). The girders are placed through the whole ER (engine room). Below the ER tank top each frame is a solid floor.

(b) A crown plate (for the main engine foundation) is placed at a different level from the DB. Bolts and nuts fillings are used to align the propeller shaft at right hight. The crown plate is transversely supported by brackets with a flange. Use of cocks to prevent the main engine from shifting. In between the engine foundation and the cocks wedges are used and bolts to secure.

(see figure 28 "Engine foundation" on page 35)


33. Which components on the engine foundation are used for alignment of the engine and propellorshaft?

Bolts and nuts fillings are used to align the propeller shaft at right hight.

(see figure 28 "Engine foundation" on page 35)

34. What technical application is nowadays used to replace the steel filling pieces after alignment?

- chemical option: chockfast = epoxy compound (not in the book) instead of steel plate.

Rec.: Cockfast is a 100% solids, inert filled, epoxy compound for holding non-precision equipment or setting anchor bolts in concrete. Designed to withstand severe environments involving high physical strengths and thermal shock. Provides 100% bearing area of machine bases and will conform to any irregular surface profiles.

More details: https://wedogrout.com/product/chockfast-gray/

- Mechanical option: steps - see following 1.-5. - are required to ensure the centreline of the crankshaft is along the centreline of the propulsion shaft, and the propeller.

1. Sighting and boring of a ship’s stern tube to establish practically the centreline of shafting, as accurately as per the design.

2. The stern tube consists of two bearings. One bearing at its forward end (called the forward bush bearing) and the other at its aft end (called the aft bush bearing). It is through the aperture of these bearings that the propulsion shaft passes.

The clearings between the bearings and the shaft are very minute, and hence the shaft centre line is to be correctly established in line with the centres of the bearings.

By maintaining this, it is ensured that the shaft centreline matches the centreline of the bearings, and the crankshaft. Again, the bearings are fitted within bosses.

3. The stern frame of the ship is the aft most structure of the hull. It is forged separately, and then attached to the remaining hull structure. The stern frame also houses the stern tube. The stern tube, in turn, houses the aft bearing.

4. The stern bearings are fitted within hollow steel cylinders within the stern tube, called bosses. Therefore, the shaft is housed within the bearings, which are housed within bosses, which again, are housed within the stern tube.

So the aft boss houses the aft bearing and the forward boss houses the forward bearing. In order to be able to match the centreline of the bearing with the bosses with that of the bearings, the bosses are ordered with a machining allowance for their internal diameter (just for the same reason why the bearings have machining allowance in their internal diameter.)

5. The stern frame is welded to the hull structure and the stern bosses are welded to the stern tube.

(Source: MarineInsight: "How Sighting, Boring and Alignment of Ship’s Propeller Shaft Is Done?")

35. Which 4 construction components are used to support the side hull?

Construction components in a transverse (and combined) framed ship:

- vertical placement of frames (as transverse constructions) to support hull plates and total shell
- frame connection to bottom frames (bilge brackets)  against transverse forces + diagonal stress
- frame connection to deck frames (deck brackets) against transverse forces + diagonal stress

(see figure 30 "side hull and deck framing" on page 36)

If stronger construction is needed: use of stronger side frames with ...

- stringer alternatively
- web plate (twice or 3 times wider than a normal frame)
- facing bar (perpendicular to the web plate)

Web frame = frame construction with bottom longitudinal, hull frames and deck beams = compulsory at Engine Room and masts

(see figure 31 + 60 "Web frame" on page 37 and 60)

Window frame = construction with frames connected to bottom frames and upper part connected to the beams = compulsory at Engine Room and masts

36. Mention 4 specific construction components to absorb longitudinal stresses?

Absorbing longitudinal stresses by construction components like ...

- continuous longitudinal bottom frames (for a better bending moment capacity)
- longitudinal framing and stiffening of Deck plate panels (beside vertical keel (or centre girder), side girder and margin plate)
- Deck transverses support the longitudinals (built from a deep web plate with flange or welded face flat, bracketed to the side frame)
- additional strengthening for ice classes (compulsory): extra longitudinal frame scantling

37. Mention 4 specific construction components to absorb transversal stresses?

Absorbing transversal stresses by construction components like ...

- transverse positioning of frames, floors, plates ... (for protecting against transverse forces of the water pressure and against diagonal stresses)
- transversal stiffening of Deck plate panels
- longitudinal deck girders support transverse framing, fitted with deck beams at every frame
- additional strengthening for ice classes (compulsory): extra transverse frame scantling

(see figure 27 ""Different type of floors"" on page 34 and figure 30 "Side hull and deck framing" on page 36)

38. What is a deck stringer?

Deck stringer = strake of platings secured to deck beam

39. Mention 4 types of decks?

Types of decks (as found in the general arrangement plan):

- water-tight deck
- strength deck
- cargo deck
- passenger accommodation deck

40. What is a roach plate?

roach plates = radius plating (round corners) to avoid high stress in the area where structures discontinue (e.g. super structure or bridge)

(see figure 34 "roach plate" on page 39)

41. Mention 3 spaces in the fore ship.

3 spaces in fore ship (front the collision bulkhead):

- Bosun's locker (under the forecastle deck) for stores and workshop / ship maintenance
- Chain locker (stowage of anchor chains)
- Fore peak tank (for ballast)

(see figure 35 "Fore ship" on page 40)

42. Mention 2 qualities of a well constructed chain locker.

A chain locker is placed highly and narrow (for self stowing of anchor chains, see page 69)

43. Explain the effect of bulbous bow and when will the maximum efficiency be achieved?

A bulbous bow is ...

(a) reducing wave resistance by reducing the size of the fore should wave, as the bow wave is brought more forward  and interferes with the fore should wave the latter is eliminated.

(b) lowering fuel costs (up to 15% under optimal conditions)

© most efficient at a specific speed and draught = when completely submerged by full load (otherwise a large bulb above the waterline when the ship is in ballast (= not loaded) is like a huge brake = dangerous).

(see figure 36 "Effect of a bulbous bow" on page 41)

44. Why are sometimes the ship’s bilges filled with concrete?

(1) to avoid spaces difficult to maintain

(2) Another reasons for using cement/beton (= concrete) in the bilge is the accumulation of "unwanted water" in other parts than the bilge itself. E.g. there is

- condensation
- leakage of pipes
- rain and/or washing water (especially in open ships)
- leakage caused by damage

(see chapter 3.8 Bilge and ballast arrangement on page 54)

Cement (= concrete) was used originally to fill in the spaces between frame heels and the keel. If the ship was designed for it to have cement, and the cement was used in displacement calculation, it should be kept there instead replacing it by more modern materials (e.g. tar / pourable foam / tar or epoxy / porable foam / epoxy).

The cement brings the the bilge up level to the top of the keel. Therefor that space must be filled to prevent water from being collected separately at every frame or else limber holes must be provided to let the water flow back to the bilge pump. Otherwise pumping the water out of such narrow spaces will be impossible.

(see also ""Concrete"" in figure 45 "Aft peak and stern frame" on page 47)

45. Mention 5 components of the panting arrangement.

Panting = stress at the ends of a vessel by increasing and decreasing water pressure on the shell plating when the vessel pitches in seaway.

Extra stiffing - longitudinal and transverse - is required to avoid deformation of the hull plating.

(a) open decks:
      1. panting stringers *, supported by
      2. panting beams (fitted at alternate frames)

      (see figure 42 "construction fore peak and chain locker" on page 45)

(b) decks (perforated flats):
      3. supported by stiffeners (from stb to pt), spaced apart no more than 2.5 meters
      4. area of performations not less than 10% of the total area of the flat plating
      5. side stringers *, spaced vertically abt. 2 meters apart and supported by
      6. web frames
      7. floors with extra high Tee bars
          (see figure 7 "steel profiles" and figure 8 "steel profiles used for frames" on page 12)
-----------------
*) The extra stringers prevent the fore end construction being deformed as a harmonica.

!! Behind collision bulkheads no panting beams are used due to loss of load capacity !!

Extra strengthening and stiffening is constructed behind the collision bulkheads:
- thick hull plating
- heavy and stronger bilge brackets
- stringer between the frames

(see figure 41 "panting arrangement aft of collision bulkhead" on page 44)

46. Mention 3 components of the pounding arrangement.

components for longitudinal (L) and transversely (T) framed double bottom (DB) in the pounding region (bottom shell area (aft of the collision bulkhead) of dynamic stress when pitching (slamming) becomes heavy and the full bow comes out of the water:

(a) Solid plate floors
- L-DB: fitted at alternate frame spaces (altern.: fitted at every 3rd frame space)
- T-DB: fitted at every frame space

(b) intercostal side girders
- L-DB: fitted at max. spacing of 3x times the transverse floor spacing (altern.: Max. spacing of 4x times the transverse floor spacing)
- T-DB: fitted at max. spacing of 3x times the transverse floor spacing

© half height intercostal side girders *: midway between full height side girders
----------
*) only for transversely framed double bottom (DB).

47. Which area of the ship is additionally strengthened for pounding?

The foreward bottom shell is strengthened additionally for pounding.

48. Mention 3 construction types of the stem post.

3 construction types of stem post:

(a) Stem bar
(b) Stem plate
© casted steel stem (on old ships)

Rec.: (b) and © are so called "soft nose" stems, which will buckle under load (e.g. collision), keeping the impact damage to a minimum.

(see figure 38 "Stem bar bow" on page 42)

49. Why are openings in the shell rounded off?   

Rounded openings reduce an impact damage.

See also ""Radius plating"" (rounded corners) and "Roach plates" on page 39.

50. Make a sketch of a stern frame and mention at least 5 components.

- arch
- rudder post
- propeller post
- sole
- heel

(see figure 44 "Single screw ship - stern frame" on page 46 and figure 45 "aft peak and stern frame" on page 47)

51. Mention 4 rudder types and make sketch of each type.

4 rudder types ...

- balance rudder
- flap rudder
- Mariner rudder
- Oertz rudder

(see figures 46-49 on pages 48-49)

52. Mention an advantage of the balance rudder.

25-30% proportion of it's lateral area is forward the turning axis of a balanced rudder.

=> reduction in torque as the centre of lateral pressure is brought nearer the turning axis.
=> A less strong steering gear engine (e.g. compared to a single blade rudder) is needed.

(see figure 46 "balance rudder" on page 48)

53. Mention 2 advantages of an Oertzrudder.

advantages of an Oertz rudder:

- enough rudder effect at low steering speed as it is two-parted.
- by using big rudder angles the water flow is more efficient -> better course stability is achieved.
- the rudder post (the small fixed part) absorbs partly the transverse forces to reduce forces in the rudder stock.

(see figure 47 "Oertz rudder" on page 48)

54. Make a sketch of a steering gear with 2 hydraulic rams and mention 4 components.

Ram-type (electro-)hydraulic steering gear ...

1. Rudder stock (with maximum torque at 35° of rudder movement)
2. Cross bar (as part of the slide mechanism) with two tiller arms
3. Two or four hydraulic rams (with cylinders and pistons)
4. Hydraulic Tubes connecting the rams with one or two pumps (Rec.: Regularly two independent pumping units service the rams with hydraulic fluid.)

(see figure 51 "steering gear mashine" on page 51)

55. Mention 4 reasons why a vessel is subdivided into several compartments by bulkheads.

Several compartments separated into (water tight)  sub divisions by at least 3 transverse bulkheads for ...

- stiffness and strength to the hull construction
- limiting the extent of flooding (by watertight divisions)
- creating segregated spaces (e.g. for ballast, fuel, cargo and engine room (ER))

56. Mention the name of 5 different types of bulkheads.

5 Types of (transverse) bulkheads:

1. collision bulkhead
    (see figure 35 "fore ship" on page 40,
     see figure 41 "panting arrangement aft of collision bulkhead" on page 44,
     see figure 42 "construction fore peak and chain locker" on page 45)

2. aft peak bulkhead
    (see figure 45 "aft peak and stern frame" on page 47)

3. fore peak bulkhead
    (see figure 42 "construction fore peak and chain locker" on page 45)

4. fore engine room bulkhead

5. aft engine room bulkhead (so far the engine room (ER) is not situated at the aft end ship construction)

57. Why is the exact location of the collision bulkhead important?

Exact position of the collision bulkhead ...

- minimum distance from the fore perpendicular in case of a collision the bulkhead will not be damaged immediately = 5-8% of the total ship length.
- maximum distance to prevent the working deck to be under water after complete flooding of the fore peak tank.

To guarantee ...

- stability after flooding/collision
- afloating with enough freeboard after flooding/collision

(see SOLAS passenger ship subdivision regulations)

58. How long must a A-3O bulkhead be flame and smoke resistant?

Structural Fire protection ...

"A-" classification ... bulkheads constructed of steel to withstand fire so the temperature on the non-fire side does not rise more than 140°C above the original temperature, nor would the temperature at any one point, including any joint, rise more than 180°C above the original temperature(during a standard fire test *).

Such bulkheads should be flame- and smoke resistant during 1 hour.
------------------
*) The standard time-temperature curve is a fair curve interpolating the following points measured above the initial temperature of the oven:

after (in minutes) / Temperature (in ° C)
   5 /  556
10 /  659
15 /  708
30 /  823  
60 /  925

59. What does the number 30 mean in an A-30 bulkhead?

Structural Fire protection ...

"A-" classification ... bulkheads constructed of steel (or equivalent metal construction), flame and smoke resistant.

These bulkheads are rated A-0 to A-60, depending on their importance and the flammability of the divided spaces.

In addition, they shall be so insulated with approved structural insulation, bulkhead panels, or deck covering that the average temperatures on the unexposed side would not rise more than 140 °C above the original temperature, nor would the temperature at any one point, including any joint, rise more than 180°C above the original temperature (during a standard fire test *), within the time listed:

Class A-60               60 minutes.
Class A-30              30 minutes.
Class A-15               15 minutes.
Class A-0                   0 minutes (i.e., no insulation requirements).
----------------
*) The standard time-temperature curve is a fair curve interpolating the following points measured above the initial temperature of the oven:

after (in minutes) / Temperature (in ° C)
   5 /  556
10 /  659
15 /  708
30 /  823  
60 /  925

60. What material is used for the construction of an A-15 bulkhead?

Structural Fire protection ...

Bulkheads which belong to the "A-"classification are constructed of steel (or equivalent metal construction). They shall be flame and smoke resistant.

61. What are the properties of the construction material of a B-15 bulkhead?

Structural Fire protection ...

"B-" classification ... same as A-Classification, but constructed of improved, incombustible material * to withstand fire so the temperature on the non-fire side does not rise more than 140°C nor will the temperature at any one point, including any joint, rise more than 225°C above the original temperature (during a standard fire test **). The withstand time is maximum 15 minutes.

–   B15 - 15 min.
–   B0   -  0 min.

The bulkheads should be flame and smoke resistant during 1/2 hour.

B-15 bulkheads are used for cabins on passenger ships.
-----------
*) Non-Combustible Materials = materials that do not burn or release flammable vapors up to 750° C, during the standard fire test.

**) The standard time-temperature curve is a fair curve interpolating the following points measured above the initial temperature of the oven:

after (in ... minutes) / Temperature (in ...° C)
   5 /  556
10 /  659
15 /  708
30 /  823  
60 /  925

62. What regulations (6) do apply for a collision bulkhead?

Regulations for collision bulkheads:
(see also SOLAS passenger ship subdivision regulations)

1. watertight bulkhead is extending from keel to the working deck
2. strength of plating is sufficient to sail in all conditions
3. bulkhead stanchions spacing is 0.6 meter maximum
4. no fitting or access is piercing the bulkhead (other than the necessary fore peak pipework = 2 pipes maximum which is fitted with valves that can be operated from above the working deck at the fore peak side)
5. no openings, manholes or doors in the bulkhead
6. bulkhead locations are at distance of 5-8% of the total length of the ship from the fore perpendicular

63. Which are the 4 major parts of the bilge arrangement?

Arrangement for bilge:

- bilge well (and scuppers), e.g. in each corner of a cargo hold, with two compartments, separated by small bulkheads (that extend approximately half the height of the well)

- self priming bilge pumps with bilge water separator

(Rec.: Cargo ships have at least 2 power driven bilge pump units in the machinery space connected to the main bilge line, working independently from the main engine. Regulated by MARPOL oil must be separated from the water by a separator. The water may not exceed 15 ppm (parts per million) of oil.)

- bilge manifold boxes

- main bilge line + suction line (with non return valves) in the engine room *

- bilge pipes (if possible are kept out of the double bottom tanks and are led through a pipe tunnel)
-------
*) Individual suction lines must be led to a central control unit (or manifold) and are provided with a "stop valve" at the manifold and a "check valve" in the bilge line.

64. What are the 4 possible reasons of the accumulation of unwanted water in the bilge?

Reasons for accumulating of unwanted water:

- condensation
- leakage of pipes
- rain and/or washing water (especially in "open ships")
- leakage caused by damage

65. Make a simple sketch of a bilge diagram, showing the main components.   

see figure 56 "simple bilge diagram and some common used symbols" on page 56

66. What are the main differences between a bilge- and a ballast system?

A bilge system pumps the water directly overboard. Individual suction lines must be led to a central control unit (or manifold) and are provided with a "stop valve" at the manifold and a "check valve" in the bilge line.

A Ballast arrangement pumps the water 1st to ballast tanks and from there to outside. Valves have to be 2-way valves as the ballast tanks must be filled as well as emptied.

(see figure 56 "simple bilge diagram and some common used symbols" on page 56)

67. What are the main differences between a bilge- and a ballast manifold?

Bilge manif...:  Individual suction lines must be led to a central control unit (or manifold) and are provided with a "stop valve" at the manifold and a "check valve" in the bilge line.

Ballast manif...: Valves have to be 2-way valves as the ballast tanks must be filled as well as emptied.

68. Mention 4 possible functions of a general service pump?

Service pumps for ...

- bilge water
- sewage
- ballast tanks
- deck wash (e.g.  for anchor gear to clean anchor chain and hawse pipes)

- emergency / distress (e.g. fire fighting, flooding)


Attached Files
.pdf   Question Catalogue 2017-2018_SHIBU with complete answers - chapter 3.pdf (Size: 124.86 KB / Downloads: 9)
Reply
#7
chapter 4 ... question catalogue

1. What does the abbreviation ILenT mean and what is the responsability of this organisation?
2. What is the responsability of a classification society and which tasks are carried out by this organisation?
3. What does the abbreviation I.M.O. mean and what is the responsability of this organisation?
4. What are the 5 equipment items regulated by ILen T and the classification society as well?
5. Mention 7 equipment components only regulated by ILenT?
6. What is a Port State Control?
7. What is the name of the document which is an inventory of all ship’s safety equipment?
8. What are the 5 main components of the steering gear?
9. Mention 5 steering gear regulations.
10. Is a non-obstructed view for the helmsman required in all directions?
11. Mention 3 required emergency steering gear components.
12. What is a rate of turn indicator??
13. Mention 4 maincomponents of the ground tackle.
14. What is the equipment number (EN) and what is it used for?
15. Which 4 elements are used in the formula of the equipment number?
16. What are the two main groups of anchor types?
17. Mention 6 parts of the stock-less anchor.
18. Mention 4 types of stock-less anchors.
19. Mention 6 parts of the stocked anchor.
20. An anchor chain is composed by several lenghts called shackles. How long is a shackle?
21. What is stud-link chain and mention 2 advantages of this chain type.
22. What part of the windlass prevents the chain from getting stuck to the gypsy wheel?
23. What is a Kenter shackle and what is the function?
24. How much chain length is needed in normal circumstances for the anchor to hold?
25. What is the maximum wear and tear that can be allowed for the anchor chain?
26. What does the expression ,,to encircle the chain”mean?
27. What is the bitter end and how is it used?
28. What is a chain stopper and how is it used?
29. What is a devil’s claw?
30. What are the two main groups of anchor winches?
31. What is the minimum (chain) speed for weighing the anchor?
32. How can we walk out the anchor?
33. How do we determine how much anchor chain has been paid out?
34. What does the expression mean: ,,the gypsywheel is clutched in”?
35. Why is the chain locker high and narrow?
36. Make a sketch of an anchor winch with an horizontal shaft and mention 6 main components.
37. Which 9 actions have to be taken to weigh anchor and to make it ready for a long voyage?
38. Which 9 actions have to be taken to make the anchor ready for dropping coming from a long voyage?
39. Can you mention a way of using the anchor as a tool for manoeuvring the ship
40. What are the 3 main reasons for quality-loss of steel?
41. What is electro-chemical corrosion?
42. What is galvanic corrosion?
43. What are the measures that can be taken to avoid galvanic corrosion?
44. What is cathodic protection?
45. What is a sacrificial anode?
46. What are the 4 main components of paint?
47. Based on different bindings, which 3 paint types can we classify?
48. Which 2 maingroups of chemical drying paint can we distinguish
49. Which 2 two-component paints do you know?
50. What are the inspection-intervals of the hull of a non-passenger vessel?
51. Mention 3 different systems to bring the toxin of the anti-fouling in contact with the fouling.
52. Which number code is used to indicate the health risk of paint during use?
53. Which character code is used to indicate the health risk of paint during use?
54. Which 7 actions have to be taken to make the ship ready for docking?
55. Which information has to be presented to the dockmaster before the ship enters the dock?
56. Describe anchor and chain maintenance during the docking periode.
57. What do the abbreviations MARPOL and SOPEP mean?
Reply
#8
my personal answers for chapter 4 ... feel free to give feedback and correct. Smile 

1. What does the abbreviation ILenT mean and what is the responsability of this organisation?

ILenT = Inspectie Leefomgeving en Transport = Human Environment and Transport Inspectorate

ILENT is supervising the legal rules (as representative of the Dutch Government) related to the equipment of a ship , based on safety care of passengers and crew.

here ""equipment"" means: all material which can contribute to a safe secure and economical management.

... also see: https://english.ilent.nl/about-the-ilt

The Human Environment and Transport Inspectorate monitors and encourages compliance with both national and European legislation and regulations in favour of a safe and sustainable human environment, safe and sustainable transport and maintaining confidence in housing associations. "

2. What is the responsability of a classification society and which tasks are carried out by this organisation?

responsability of the Classification Society:
- quality of the ships' construction
- safe navigation

=> Tasks:
- thoroughly control of ships' equpment
- Certificate of Class for hull and machinery = certificate upon completion of construction
- control and inspect safety equipment of professional sailing vessels (up to 500 tons, a maximum of 36 passengers, from 12 to 40 meters) by Register Holland (RH) = Dutch Classification Society

In addition to the IMO rules and regulatoins Classification Societies are allowed to make their own regulations."

3. What does the abbreviation I.M.O. mean and what is the responsability of this organisation?

IMO = International Maritime Organisation.

- rule sets
- conventions
- amendments

IMO Maritime Safety Committee:
- fire protection
- ship design and
- equipment"

4. What are the 5 equipment items regulated by ILen T and the classification society as well?

equipment regulated by Classification Society and ILenT:

- Steering gear
- Ground tackle
- Rudder angle indicator
- Tachometer
- Rate of turn indicator (> 100,000 GT)"

5. Mention 7 equipment components only regulated by ILenT?

equipment only regulated by ILenT:

1. Life saving appliances: Lifeboats, life rafts, MOB-boats, floating equipment, life buoys, life jackets, survival suits.

2. Safety appliances: Line throwing apparatus, pyrotechnics, pilot ladder, fire detection and extinguishing, breathing apparatus (BA), 1st aid kit and stretcher, emergency muster list, safety plan, emergency escape breathing device (EEBD), search and rescue radar transponder (SART), Voice data recorder (VDR), emergency positoin indicating radio beacon (EPIRB)

3. Navigation aids:

... see page 63

6. What is a Port State Control?

Port State Control (PSC) is the inspection of foreign ships in national ports to verify that the condition of the ship and its equipment comply with the requirements of international regulations and that the ship is manned and operated in compliance with these rules.

Many of IMO's most important technical conventions contain provisions for ships to be inspected when they visit foreign ports to ensure that they meet IMO requirements.

see more details:  http://www.imo.org/en/OurWork/MSAS/Pages...ntrol.aspx

7. What is the name of the document which is an inventory of all ship’s safety equipment?

The certificate called ""Cargo Ship Safety Equipment Certificate"" shall be issued after survey to a cargo ship of 500 gross tonnage and over which complies with the relevant requirements of chapters 1-1 and Il-2 and Ill and any other relevant requirements of SOLAS 1974.

The certificate called ""Passenger Ship Safety Certificate"" shall be issued after inspection and survey of a passenger ship which complies with the relevant requirements of chapters II-1, Il-2, III, IV and V and any other relevant requirements of SOLAS 1974."

8. What are the 5 main components of the steering gear?

main components of Steering gear:

- steering wheel
- automatic pilot
- transfer system (between bridge signal and steering engine)
- steering engine
- rudder stock
- rudder

9. Mention 5 steering gear regulations.General steering gear regulations:

- Rudder is strong enough to withstand putting rudder maximum ...
  (a) ... from one side to the other side, within a specified time frame.
  (b) ... rudder angle running ahead and aft.
- If wheel or helm is moved to starboard the ship should alter to starboard.
- an adequate emergency steering gear is required (backup system)
- The wheel or helm is placed where the helmsman has a non-obstructed view over the fore part of the ship.

10. Is a non-obstructed view for the helmsman required in all directions?

No. - The wheel or helm is placed where the helmsman has a non-obstructed view over the fore part of the ship.

11. Mention 3 required emergency steering gear components.Emergency Steering Gear ... equipment which is necessary to steer the ship in the event of failure of the main steering gear.

Small vessels ...
- hydraulic emergency pump at the steering wheel.

Ships with a rudder stock over 230 mm diameter ...
- mechanical main steering gear. The steering system is a ""double system"" with two pumps and four cylinders (see figure 51 ""Steering gear machine on page 51).

12. What is a rate of turn indicator?

ROTI = Rate of Turn Indicator.

It indicates the instantaneous rate at which the ship is turning. The swcale shall be marked in intervals of one degree per minute. Specifically big vessels and river barges use ROTI during mooring.

A ROTI is compulsory on ships with a radar system (see SOLAS Chapter V., Regulation 19: Navigation System and Equipment).

13. Mention 4 maincomponents of the ground tackle.The ground tackle is for mooring a vessel away from a pier or other fixed moorings. It consists of:

- anchors
- chains
- chain stoppers
- windlass/winches

14. What is the equipment number (EN) and what is it used for?

Equipment number = EN.

It is used to determine the minimum weights and dimensions of anchors, chains, ropes ...

The EN can be found on the Midship Section drawing.

15. Which 4 elements are used in the formula of the equipment number?

Standard EN number is calculated as following:

EN = D 2/3 + 2x (HxB) + 0.1 A

(D = Displacement, H = Height above load line, B = Breath, 2HB = Influence of frontal winds, A = Lateral surface ship above water, influnece of side winds.)

EN used by Register Holland (and better suited for sailing vessels with high rigging) is calculated with the equation:

EN = D 2/3 + 2x O rd + O rig + 0.1 A

(O rd = athwart-ship's hull surface, O rig = rigging surface)

16. What are the two main groups of anchor types?

stocked anchors (old fashion) and stockless anchors (on sea going vessels)

17. Mention 6 parts of the stock-less anchor.

Components of a stock-less anchor:

- shank
- ring/shackle
- arm
- flukes
- pivot
- shoulder or horn

18. Mention 4 types of stock-less anchors.

Types of stock-less anchors:

- Spek anchor (always correct position of hawse)
- Pool Anchor
- d'Hone anchor
- Danfort anchor
- Delta anchor (HHP = high holding power anchor, for offshore and dredging)

19. Mention 6 parts of the stocked anchor.Components of a stocked anchor:

- ring/shackle
- shank
- crown with arm and flukes
- stock with acorn
- breast
- wedge

20. An anchor chain is composed by several lenghts called shackles. How long is a shackle?

The Anchor chain has a different number of lengths = shackle (or shot).

Regularly each shackle has a length of 15 fathoms = 15 x 1.83 m = 27.45 m. Nowadays are also used shackles of 30 (2x 15) x 1.83 m = 54.90 m

21. What is stud-link chain and mention 2 advantages of this chain type.

An anchor chain, called stud-link chain, consists of links with studs to prevent the chain from twisting and the links from pounding on adjacent links.

The studs further strengthen the chain up to 15%. (Rec.: The length of a standard link is 6 times its diameter and width is 3.6 times its diameter.)

22. What part of the windlass prevents the chain from getting stuck to the gypsy wheel?

Chain shackels are inter-connected by a Kenter shackle (with detachable link). The end links of a shackle are without stud. Each shackle consists of an odd number of links to get the Kenter shackle in a horizontal position at the gypsy wheel of the winch / windlass.

When raising the anchor and the rope end, the first link of the anchor chain should be in a vertical position at the gypsy wheel through wich all kenter shackles will follow in horizontal position at the gypsy wheel ... and cannot be trapped in the gypsy wheel.

23. What is a Kenter shackle and what is the function?

Chain shackels are inter-connected by a Kenter shackle (with detachable link). The round part of the shcakle is placed towards the anchor to prevent obstruction during running out the anchor. (Rec.: The anchor shackle is connected to a bending shackle and an end link. A swivel is placed between end-link and chain to reduce kinking or twisting of the chain.)

A Kenter shackle is made of two C-shape half links with a removable stud, locking pin and lead plug to lock the pin (see figure 65 on page 68).

24. How much chain length is needed in normal circumstances for the anchor to hold?

At normal circumstances : length of anchor chain = 30 fathom (= 54.90 m) + water depth are needed.

25. What is the maximum wear and tear that can be allowed for the anchor chain?

Thickness of the anchor chain is the diameter of the thinnest part of the link.

More than 10% wear and tear is not allowed. (Rec.: An anchor chain made of U2 or U3 steel quality should be certified before use.)

26. What does the expression ,,to encircle the chain”mean?

"To encircle the chain" =
When the part of the chain that is often used, has wear and tear, we change that part with a part not often used

(Rec.: Max. allowable
thickness reduction 10 %)


27. What is the bitter end and how is it used?

The end of the chain, the bitter-end is secured to an end connection in the chain locker, with release outside the locker. (Rec.: A red hammer is compulsory to be available near the bitter-end in case of emergency.)

28. What is a chain stopper and how is it used?

The Chain stopper is positioned between the hawse pipe and winch. It is used when ...

1.) letting go the anchor
2.) raising the anchor and bring it back in the hawse.

Its function:
- absorbing the pull of the chain by diverting it to the hull and prevent damage to the winch
- locks the chain and prevents it from uncontrollabla running out in case the band brake is slipping.

29. What is a devil’s claw?

The devils claw is an extra security. It acts as a perament stopper.

It is used between the winch and chain. It is a claw to be put on a link of the chain and tightened by a turn-buckle. (see figure 69 on page 70).

30. What are the two main groups of anchor winches?

horizontal shaft and vertical shaft windlass with electrical engine or hydraulic and electrical-hydraulic or steam propulsion.

... with claw (clutch) coupling.
... with pinion.

31. What is the minimum (chain) speed for weighing the anchor?

10 m / min. is the minimum speed of weighing the anchor.

32. How can we walk out the anchor?

Walking out (and heave) the anchor is done by powered gypsy wheel. Letting go anchors wihtout power is only controlled by the band brake. (Rec.: To connect or disconnect the gypsy wheel to the main shaft, a clutch or a toothed wheel pinion is fitted.)

33. How do we determine how much anchor chain has been paid out?

The anchor chain is marked, by colour markings or wire markings.

Colour markings (one shackle) ...
- Kenter shackle painted red and
- one link on each side painted white for the next shackles.

Wire markings (one shackle) ...

34. What does the expression mean: ,,the gypsywheel is clutched in”?

A winch must be capable to to operate both anchor chains independently and when the gypsy whell is in use, then the claw is cluthced in and the warping drums may not be in operation.

35. Why is the chain locker high and narrow?

The locker is high and narrow to make it self stowing.

36. Make a sketch of an anchor winch with an horizontal shaft and mention 6 main components.main components of an anchor winch:

Scetch of an anchor winch
- base
- driving shaft (e.g. connected with an electric/hydraulic engine)
- gypsy wheel
- drum clutch (with control lever)
- warping drum
- (drum) band brake
- hand driven wheel (with spikes)

37. Which 9 actions have to be taken to weigh anchor and to make it ready for a long voyage?

Make the anchor ready for sea (house the anchor):

1. Briefing of the crew: ""How much cable is out? ... Stand by for heaving up. ... Put the windlass in gear. ... How is the cable leading? Heave up port / starboard / both cable(s). ... How much weight is on the cable? ... Stop heaving. ... How many shackles are left (to come in)? ... Attention! Turn in cable(s).""

2. Wear safety goggles

3. Check if friction band brake is tight.

4. Start deck wash pump and hydraulic pump or electrical engine on forecastle

5. Open chain stopper and devil's claw

6. Clutch in the gypsy wheel to connect it with the main shaft (or use the toothed wheel pinion)

7. Untight the friction band brake

8. House anchor in hawse and secure (see 9. -12.)

9. Tighten again friction band brakes.

10. Secure with chain stopper and devil's claw to absorb the pull of the chain by diverting it to the hull and prevent damage of the winch and to prevent it from uncontrollable running out in case the band brake is slipping.

11. Release ocean lashings

12. Close spill pipes (e.g. with cement)

13. leave anchorage place, switch off anchor light and haul down the anchor ball.

38. Which 9 actions have to be taken to make the anchor ready for dropping coming from a long voyage?

Make the anchor ready for dropping (coming from a long voyage):

1. Briefing of the crew: ""Stand by port / starboard / both anchor(s) for letting go. ...  Walk out the anchor(s). ... We are going to anchorage. ... We will let go port / starboard / both anchor(s). ... Put ... shackles in the water / in the pipe / on deck.""

2. Check if friction band brake is tight.

3. Open spill pipe (from cement)

4. Release ocean lashings

5. Start deck wash pump and hydraulic pump or electrical engine on forecastle

6. Open chain stopper and devil's claw

7. Manoever the ship to the anchorage place

8. Wear safety goggles

9. Untight the friction band brake. - Use the brake to control the running speed of the chain.
- If dropping the anchor without power (just by gravity) bring the anchor shank out of the hawse pipe first in which it was stowed. The gypsy wheel is clutched out.
- When the bottom is rocky or relative deep water, bring anchor out with power. This will prevent anchor damage or foul anchor. The gypsy wheel must be clutched in before the friction band brake is being untight.

10. After dropping the anchor: Tighten the band brake, secure with chain stopper and devil's claw to absorb the pull of the chain by diverting it to the hull and prevent damage of the winch and to prevent it from uncontrollable running out in case the band brake is slipping.

11. Switch on Anchor lights / Hoist the Anchor ball. Check the anchor position by bearings.

39. Can you mention a way of using the anchor as a tool for manoeuvring the ship

Ship's anchors can be used not only for berthing but also during maneuvering through channels and other similar areas with restriction in movement.

Dredging anchors is a method which is used to assist a ship in maneuvering during unavailability or inability of tugs to assist as required.

40. What are the 3 main reasons for quality-loss of steel?reasons for quality loss of steel:

- corrosion
- mechanical wear + tear
- erosion by (bubble) cavitation

41. What is electro-chemical corrosion?

Rust is an example of electro-chemical corrosion.

Rust = Fe2 O3 (iron oxide) ... a slow and not aggressive process of reaction between oxygen and iron. (Rec.: The iron gives up electrons, while the oxygen gains electrons.)

42. What is galvanic corrosion?

Pitting is an example of galvanic corrossion, as an aggressive process (compared to electro-chemical corrosion).

- 2 different metals (galvanic couple) are located together in a corrosive electrolyte (e.g. like salt water).
- electroloyte is a substance which ionizes when dissolved in an ionizing solvent like water
- a galvantic couple forms between two dissimilar metals.

43. What are the measures that can be taken to avoid galvanic corrosion?

metals are classified into a galvanic series. This represents the electrical potential the metal develops in a given electrolyte against a standard electrolyte.

The first metal in this series are more likely to corrode quickly than the next in the series.

44. What is cathodic protection?The method of passive cathodic protection = use of sacrificial anodes:

- the most based metal (like magnesium, aluminium, zinc, iron) becomes the anode (= positive)
- the most precious (nobel) metal (like silver and gold) becomes the cathode (= negative)

See also ICCP = Impressed cathodic protection system on page 74.

45. What is a sacrificial anode?

The anode (or sacrificial metal) corrodes and deteriorates faster than it would alone, while the cathode deteriorates more slowly than it would otherwise, by the continuous flow of current from base to precious metal. This process generates dissolving ions from the less noble metal in the water.

46. What are the 4 main components of paint?

Paint contains 4 components:

- binding agent
- solvent
- pigment
- additives for drying, filling and flowing.

47. Based on different bindings, which 3 paint types can we classify?

3 paint types based on different binding agents:

- conventional paint, based on linseed oil (also red lead and boat varnish)
- chlorine latex paint
- epoxy paint based on epoxy resin

48. Which 2 maingroups of chemical drying paint can we distinguish

Beside physical drying paint and oxidative drying paint there exist chemical drying paint.

The chemical drying paints are sub-divided in:
- Alkyd resin paint
- two component paint

49. Which 2 two-component paints do you know?

Two-component paints:

- PU ... Poly-urethane paint ... very resistant to water, dirty air and (all kind of) chemicals at processing temp of min. 15° Cels.

Expensive and very sensitive to humidity => minimum 3 layers to be painted in a dry indoor environment. Layers are tough and lifespan is 2x longer than conventional pints layers.

- Epoxy ... high mechanical and chemical resistances at normal processing temp (btw. 10-25° Cels.)

Even in thin film, it will resist (under water) to oils, most acids, saline environments while guaranteeing a high scratch resistance and long lasting chemical resistance in boat bilges, tanks, interiors and maintenance inspections.

50. What are the inspection-intervals of the hull of a non-passenger vessel?

Complete hull of a non-passenger vessel must be examined at least twice every 5 years. (While the complete hull of passenger vessel must be examined at least once every 12 months.)

The maximum time lapse between two inspections of a hull of a non-passenger vessel should not exceed 36 months.

(Rec.: Authorities from the ILenT division ""shipping"" are authorized to demand shorter hull inspection periods for old or bad maintained vessels. Inspection regulations don't mentoin dry docking. A so called ""in water survey"" is possible when the underwater hull is coated with a special paint system like epoxy tar. Between 30 and 36 months the hull must be examined by divers, specifically at earlier applied markings. Dry docking is compulsory for an extensive inspection after 60 months.)

According the SOLAS convention regular surveys are required. These regulations are incorportaed in the Netherlands Merchant Shipping Legislatoin for ships to get a safety certificate.

51. Mention 3 different systems to bring the toxin of the anti-fouling in contact with the fouling.

3 different systems to bring the toxin in contact with the fouling:

- tough layer from which the biocide releases slowly. (Rec.: After some time the toxic effect decreases, so an excess of toxin is needed.)

- Soft layer from which the biocide attached to the binding agent. (Rec.: This binding agent dissolves slowly.)

- Self-polishing layer. The outer layer continuously fell of which gives an optimal control of the biocide release.

52. Which number code is used to indicate the health risk of paint during use?

By the Dutch Painting Board a code is invented because many harmful elements are used during painting.

The code is with a character and a number, like A-1, C-0 or D-1.

(Number 0 = Non-volatile elements are not harmful.)
Number 1 = Non-volatile elements are harmful to swallow or to inhale with sanding dust.

53. Which character code is used to indicate the health risk of paint during use?

By the Dutch Painting Board a code is invented because many harmful elements are used during painting.

The code is with a character and a number, like A-1, C-0 or D-1.

(Character A = No specific precautions needed.)
Character B = Inhalation of fumes can be harmful. Ventilation needed.
Character C = Inhalation of fumes is harmful. Ventilate when using a brush. Remove fumes by suction when spraying.
Character D = Inhalation of fumes is dangerous. Use face guard.

54. Which 7 actions have to be taken to make the ship ready for docking?

"Ready for docking" means:

- tanks + holds to be cleaned and free of gas.
- certificate ""gas proof"" (by labor inspection) before (a) entry and cleaning of enclosed space  (like tanks) (b) welding and cutting starts. - Validation: 12 hours.
"permit to work" (PTW) by safety office before starting high risk work
- to clean the ship following Marpol. E.g. no chains and lines/ropes stored on deck. Mark obstacles on deck by white or yellow strips or paint.
- cranes or derricks parked in the jib
- deck and tweendeck pontoons closed for safety and rain
- clean and lock toilets, not connected to sewage tank
- to prepare dock list for all duties
- 2nd check if cutting and welding can be executed safely
- check there is no fire risk on the other side of a bulkhead
- appropriate trim before entering the dock

55. Which information has to be presented to the dockmaster before the ship enters the dock?

Informations for the dockmaster (before the ship enters the dock):

- docking plan: it shows where the ship can be supported by the keel blocks. The place of the longitudinal and transverse bulkheads, position of shell openings, drain plugs, keel floor plates etc. are displaced in this plan, too.

- Draft fore and aft

- Length, breadth and displacement

- Rise of the floor, to prepare the keel blocks

- Date of cargo and ballast still on board, to place additional keel blocks

56. Describe anchor and chain maintenance during the docking periode.

During the maneuver "entering the dock" the anchors are ready and standby. When the ship is just about to enter the dock, the anchors must be secured. Lines or steel wires to handle the vessel are ready to use. The dock master supervises from now on the operation. The time should be noted in the logbook. The main engine will be stopped.

57. What do the abbreviations MARPOL and SOPEP mean?

The International Convention for the Prevention of Pollution from Ships, 1973 as modified by the Protocol of 1978 (MARPOL 73/78, MARPOL is short for marine pollution and 73/78 short for the years 1973 and 1978) is one of the most important international marine environmental conventions.

The Shipboard Oil Pollution Emergency Plan, or SOPEP, is a prevention plan carried on board tankers >150 GT and other vessels >400 GT. In this plan you get an overview of possible procedures in case of an oil spill."
+++


Attached Files
.pdf   Question Catalogue 2017-2018_SHIBU with complete answers - chapter 4.pdf (Size: 113.62 KB / Downloads: 7)
Reply
#9
The existing Flash card set for FIBU is updated. - Direct download as ZIP file here. This updated version (dated on 30/03/2018) contains all answers given by our teacher Cees K. with email on 28th March 2018)

Good luck for the re-examen on 7th April 2018.  Smile
Reply
#10
... with request the answers which have been not clear from myself (see "red text marks") are being answered today by our teacher Cees K.

------ email message ------------

Subject: Re: EZS - SHIBU ... KZV re-examen on 7th April
Date: Wed, 28 Mar 2018 18:15:26 +0200
From: Ceeskapteijn <...@gmail.com>
To: ...@...

...

Hereby answers to questions mentioned:

CH.1 Q17: Manganese, Mn.(page 11)

CH.2 Q7:   escape routes, lifesaving equipment, firefighting equipment, etc.etc. (have you never seen a safety plan?)
        Q19: If the waterplane is for example L=20,B=6, area is 120 m2, draught increases with 0,01 m.
                displacement is 1,2 m3 (20x6x0,01)
        Q20: top layer of the box spar and bottom layer (page 21 top)
        Q41: Certificate of class. (page 23)
        Q42: Safety certifcate , int. tonnage certificate, Int.Loadline certificate (page 23)

CH.3 Q26: look at fig.26 page 33 and fig. 27 on page 34
        Q34 ; shockfast =epoxycompound (not in the book) in stead of steel plate.
        Q44: to avoid spaces difficult to maintain.
        Q68: firefighting, sewage, bilge, ballast .

CH.4 Q26: When the part of the chain that is often used, has wear & tear,
                we change that part with a part not often used.
                (max. allowable thickness reduction 10 %)

Most answers are in the book, you have to look  them up.

Lot of succes!

Greetings,
Cees Kapteijn
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)