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First Semester (BSMT) > MT101 Principal dimensions and structural parts > Flashcards

MT101 Principal dimensions and structural parts Flashcards

1
Q

is the length of a ship along the waterline from the forward surface of the stem, or main bow perpendicular member, to the after surface of the stern post, or main stern perpendicular member

A

Length between perpendiculars

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2
Q

is a vertical line extending from the point at which the stem of the vessel is intersected by the design load waterline on the profile view.

A

forward perpendicular

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3
Q

has been located to the outside plate or forward side of the stem

A

forward perpendicular

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4
Q

is the line perpendicular to the constructed waterline and the rudder post

A

Aft Perpendicular

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5
Q

is the length measured at the existing waterline from forward to aft end of the ship. It varies with the draft of the ship

A

waterline length (originally Load Waterline Length, abbreviated to LWL)

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6
Q

is the length measured between the extreme ends of the ship from forward to aft

A

Length over all

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7
Q

A middle parts of the ship

A

MIDSHIP

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8
Q

is a vertical line passing through the mid point of the LBP

A

MIDSHIP or AMIDSHIPS

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9
Q

is the distance taken at midship of vessel from port to starboard ( right to left).

A

Beam ( Breadth)

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10
Q

is the vertical distance from deck to waterline

A

Freeboard

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11
Q

is measured at the middle of the length, from the top of the keel to the top of the deck beam at the side of the uppermost continuous deck

A

Depth

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12
Q

is the vertical distance measured along the ship sides from the bottom of the keel to the waterline

A

Draft

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13
Q

outward curvature of a ships hull surface above the waterline

A

flare

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14
Q

is the narrowing of a ship’s hull with greater distance above the water-line.

A

Tumblehome

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15
Q

it is present when the beam at the uppermost deck is less than the maximum beam of the vessel

A

Tumblehome

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16
Q

is 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 centerline above the height of deck at side

A

Camber

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17
Q

is measured from the base line to the heel of the upper deck beam at the ship’s side amidships

A

Depth moulded

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18
Q

is measured at the midship section is the maximum moulded breadth of the ship

A

Breadth moulded

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19
Q

is taken from the lowest point of the keel to the summer load line.

A

Extreme draft

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20
Q

represents extreme draft

A

Draft marks

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21
Q

is the rise of the bottom shell plating above the baseline , this rise is measured at the line of the moulded beam

A

Rise of floor or Dead rise

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22
Q

is a horizontal line drawn at the top of the keel plate.All vertical moulded dimensions are measured relative to this line.

A

Base line

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23
Q

is a curvature of decks in the longitudinal direction.measured as the height of deck at side at any point above the height of deck at side amidships

A

sheer

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24
Q

is the section of the hull where the mid-ship cross section remains the same over a number of stations

A

Parallel Middle Body

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25
Q

is not seen on all ship types and is most apparent on tankers,Container ships, and Bulk Cargo carriers

A

Parallel Middle Body

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26
Q

The immersed body of the vessel aft of the parallel middle body

A

run

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27
Q

The immersed body of the vessel forward of the parallel middle body.

A

entrance

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28
Q

is a storage place where the cargo is loaded and stored safely

A

CARGO HOLD

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29
Q

is a cover for the cargo holds for the protection of the cargo from the various natural and atmospheric conditions

A

HATCH COVER

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30
Q

These are the tanks made in the ship’s hull or say in the ship’s bottom part to carry the _ i.e. sea water to enable the ship to gain some stability and draft

A

BALLAST TANK

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31
Q

These are the tanks constructed in the ship’s hull to store the ship’s fuel oil i.e. diesel and heavy oil to run the ship’s machinery.

A

BUNKER TANK

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32
Q

is the propulsion machinery spaces of the vessel. To increase a vessel’s safety and chances of surviving damage, the machinery necessary for operations may be segregated into various spaces

A

Engine room, or ER

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33
Q

tank which is at the bow or stern end of a ship and is low in the ship, usually kept empty and dry but sometimes used to carry potable water

A

PEAK TANK

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34
Q

is a ship hull design and construction method where the bottom of the ship has two complete layers of water tight hull surface: one outer layer forming the normal hull of the ship

A

DOUBLE BOTTOM TANK

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35
Q

is an opening in the deck of a vessel to provide access below leading to a hold, compartment, or cellar.

A

Hatchway

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36
Q

is a space between two continuous decks in the hull of a vessel, as between a shelter deck and a freeboard deck

A

Tween deck

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37
Q

is an upright wall within the hull of a ship which separate the hull into different rooms and compartments.

A

BULKHEAD

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38
Q

is a temporary enclosure built within, or in pairs across, a body of water and constructed to allow the enclosed area to be pumped out, creating a dry work environment for the major work to proceed

A

cofferdam (also called a coffer)

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39
Q

is a room, building, or compartment in which pumps are housed or from which they are controlled

A

Pump room

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40
Q

is a tank intended primarily for the carriage of liquids or gases and includes appurtenances, reinforcements, fittings, and closures

A

Cargo tank

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41
Q

a tank in an oil tanker which is used to collect the oil and water mixtures from cargo tanks after tank washing

A

Slop tank

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42
Q

STRUCTURAL PARTS OF THE SHIP

A

smokestack or funnel. stern. propeller and rudder. portside and starboard side. anchor. bulbous bow. bow. deck. superstructure

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43
Q

is the smokestack or chimney on a ship used to expel boiler steam and smoke or engine exhaust.They are also commonly referred to as stacks

A

FUNNEL

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44
Q

is the back or aft-most part of a ship or boat, lies opposite the bow, the foremost part of a ship

A

STERN

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45
Q

is a rotating fan-like structure which is used to propel the ship by using the power generated and transmitted by the main engine of the ship

A

PROPELLER

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46
Q

is a device used to steer a ship, boat, submarine, hover craft or aircraft

A

RUDDER

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47
Q

is a device, normally made of metal, used to connect a vessel to the bed of a body of water to prevent the craft from drifting due to wind or current

A

ANCHOR

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48
Q

can either be temporary or permanent

A

anchors

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49
Q

The word derives from Latin _, which itself comes from theGreek ἄγκυρα _

A

ancora. ankura

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50
Q

is a protruding bulb at the bow (or front) of a ship just below the waterline

A

BULBOUS BOW

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51
Q

modifies the way the water flows around the hull, reducing drag and thus increasing speed, range, fuel efficiency, and stability

A

bulb

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52
Q

is the front most part of a ship which cuts the water along its sides as the ship proceeds.

A

bow

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53
Q

is a permanent covering over a compartment or a hull of a ship

A

deck

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54
Q

is the horizontal structure that forms the “roof” of the hull, strengthening it and serving as the primary working surface

A

primary or upper deck

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55
Q

upward extension of an existing structure above the main deck (baseline)

A

superstructure

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56
Q

are very important to a ships safety

A

principal structures

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57
Q

both depends on a ships structure and should never be taken for granted

A

life and property

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58
Q

principal structural member of the ship

A

hull, keel, decks, bulkheads

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59
Q

is the main body of ship exclusive of mast superstructure and forecastle

A

hull,

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60
Q

is the longitudinal structure along the centerline at the bottom of a vessel’s hull, on which the rest of the hull is built, in some vessels extended downward asa blade or ridge to increase stability

A

KEEL

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61
Q

the main structural member and backbone of a ship or boat, running longitudinally along the centre of the bottom of the hull from stem to stern

A

keel

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62
Q

It may be made of timber, metal, or other strong, stiff material. Traditionally it constituted the principal member to which the ribs were attached on each side and to which the stem and sternpost were also attached.

A

keel

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63
Q

Another type of main keel—properly, the _ —is a vertical downward extension of the boat’s hull, narrowly V-shaped;

A

“full keel,” or “ballast keel”

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64
Q

it is usually ballasted or weighted for stability and lateral resistance

A

“full keel,” or “ballast keel”

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65
Q

Vertical partition walls which subdivide the ship interior into water tight compartments

A

Bulkheads

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66
Q

reduce the extent of seawater flooding in case of damage and provide additional stiffness to the hull girder. They can be flat or corrugated

A

Bulkheads

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67
Q

technically defined as the area built up over the sternpost, extending upwards from the counter rail to the taffrail.

A

stern

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68
Q

lies opposite the bow, the foremost part of a ship. Originally, the term only referred to the aft port section of the ship, but eventually came to refer to the entire back of a vessel.

A

stern

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69
Q

TYPES OF SHIPS

A

General Cargo* Oil, Chemical and Gas Tankers* Bulk Carriers* Combination Carriers* Container* RO-RO / CAR CARRIER* Passenger

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70
Q

is any sort of ship or vessel that carries cargo, goods, and materials from one port to another.

A

general cargo (cargo ship or freighter)

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71
Q

are usually specially designed for the task, often being equipped with cranes and other mechanisms to load and unload, and come in all sizes

A

Cargo ships

72
Q

is a merchant ship designed for the bulk transport of oil.

A

oil tanker, also known as a petroleum tanker

73
Q

two basic types of oil tankers

A

crude tanker and the product tanker

74
Q

move large quantities of unrefined crude oil from its point of extraction to refineries.

A

Crude tankers

75
Q

generally much smaller, are designed to move refined products from refineries to points near consuming markets

A

Product tankers

76
Q

is a type of tanker ship designed to transport chemicals in bulk

A

chemical tanker

77
Q

As defined in _ , chemical tanker means a ship constructed or adapted for carrying in bulk any liquid product listed in chapter 17 of the International Bulk Chemical Code.

A

MARPOL Annex II

78
Q

is a merchant ship specially designed to transport unpackaged bulk cargo, such as grains, coal, ore, and cement in its cargo holds. It is commonly known as loose cargo

A

bulk carrier, bulk freighter, or bulker

79
Q

is a ship designed to be capable of carrying wet or dry cargoes.The idea is to reduce the number of empty (ballast) voyages, in which large ships only carry a cargo one way and return empty for another.

A

ore-bulk-oil carrier, also known as combination carrier or OBO

80
Q

are cargos hips that carry all of their load in truck-size intermodal containers, in a technique called containerization

A

Container ships

81
Q

They are a common means of commercial intermodal freight transport and now carry most seagoing non-bulk cargo

A

Container ships

82
Q

are vessels designed to carry wheeled cargo, such as cars, trucks, semi-trailer trucks, trailers, and railroad cars, that are driven on and off the ship on their own wheels or using a platform vehicle, such as a self-propelled modular transporter.

A

Roll-on/roll-off (RORO or ro-ro) ships

83
Q

use a crane to load and unload cargo

A

lift-on/lift-off (LoLo) vessels

84
Q

is a merchant ship whose primary function is to carry passengers. The category does not include cargo vessels which have accommodations for limited numbers of passengers

A

Passenger Ship

85
Q

is a type of vessel that maneuvers other vessels by pushing or pulling them either by direct contact orby means of a tow line

A

tugboat or tug

86
Q

is a boat or ship used to catch fish in the sea, or on a lake or river.

A

FISHING VESSEL

87
Q

refers to the practice of loading barges(lighters) aboard a bigger vessel for transport.

A

lighter aboard ship (LASH) system

88
Q

It was developed in response to a need to transport lighters, a typeof (usually but not always) unpowered barge, between inland waterways separated by open seas

A

LASH SHIP

89
Q

are typically towed or pushed around harbors, canals or rivers and cannot be relocated under their own power.

A

lighters

90
Q

are cargo vessels used to transport cattle, sheep, goats, cows, buffaloes, etc.

A

Livestock carriers

91
Q

They are crucial links in the world’s food supply chain where several nations profit from exporting cattle at higher rates, and many countries access good quality meat and other extractives

A

Livestock carriers

92
Q

of a ship is its width at its widest point

A

Beam

93
Q

is the distance between planes passing through the outer extremities of the ship

A

maximum beam(BMAX)

94
Q

is the maximum width where the hull intersects the surface of the water.

A

Beam at waterline (BWL)

95
Q

is a force which tends to break or shear a beam across (perpendicular to)its major axis

A

Shear force

96
Q

at any point on abeam is the total moment tending to alter the shape of the beam

A

Bending moment

97
Q

are forces pushing one part of a body in one direction, and another part of the body in the opposite direction

A

Shear Force

98
Q

is the algebraic sum of the vertical forces acting to the left or right of a cut section along the span of the beam

A

Shear Force

99
Q

When two external parallel forces act in opposite directions on any part of a structure to break it apart or shear it, the forces are known as

A

shearing forces

100
Q

are measured in tonnes.

A

shearing forces

101
Q

the stress that may break or shear the structure apart

A

Shearing stress

102
Q

is the reaction induced in a structural element when an external force or moment is applied to the element causing the element to bend

A

bending moment

103
Q

is the algebraic sum of the moment of the forces to the left or to the right of the section taken about the section

A

bending moment

104
Q

is the amount of bending caused to the ship’s hull by external forces

A

bending moment

105
Q

When the ship’s ends are supported by crests of a wave known as

A

sagging

106
Q

positive bending

A

sagging

107
Q

When the ship is riding the crest of a wave at its midships, the bending moment is known as

A

hogging

108
Q

negative bending

A

hogging

109
Q

are measured in tonne- metres

A

BENDING MOMENT

110
Q

is the straining of a ship heavily loaded amidships and more lightly forward and aft, causing the bow and stern to be higher than the middle section

A

SAGGING

111
Q

is the straining of a ship lightly loaded amidships and more heavily forward and aft, causing the bow and stern to be lower than the middle section

A

hogging

112
Q

are usually expressed in terms of percentage, with 100% being the ceiling limit.

A

Stresses

113
Q

must be kept to the minimum as practicable and must never exceed 100%. It is recommended that as far as possible, _ be maintained below 90% or thereabout.

A

Hull stresses

114
Q

may be reduced by adjusting the vessels Ballast / Fuel condition

A

High stresses

115
Q

Ship floating at rest in still water

A

Static forces

116
Q

Two major forces acting

A
  • the weight of the ship acting vertically down- buoyancy acting up
117
Q

refers to a constant force applied to a stationary object

A

static force

118
Q

is too weak to move an object because it is being countered by equally strong opposite forces

A

static force

119
Q

is the pressure exerted by a fluid at hydrostatic equilibrium on the contact surface due to gravity

A

Hydrostatic pressure

120
Q

is due to the motion of the ship and the sea the structural stresses, caused by the above forces

A

DYNAMIC FORCES

121
Q

DYNAMIC FORCES to which the ship structure is subjected may be categorized as:

A

Longitudinal stresses (hogging and sagging) Transverse stresses (racking and the effects o water pressure) Local dynamic stresses (panting and pounding)

122
Q

LONGITUDINAL STRESSES

A

Hogging and sagging

123
Q

If the buoyancy in midship is greater the ship will

A

Hogging

124
Q

If the buoyancy in midship region is lesser the weight of the ship will

A

sagging (sag)

125
Q

TRANSVERSE STRESSES

A

Racking and WATER PRESSURE

126
Q

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

A

Racking

127
Q

acts perpendicular to the shell of the ship, increasing with depth.

A

Water pressure

128
Q

The effect is to push the ship’s sides in and the bottom up. It is resisted by frames, bulkheads, floor and girders

A

Water pressure

129
Q

LOCAL DYNAMIC STRESSES

A

panting and pounding

130
Q

is an in and out motion of the plating in the Bow of a ship and it cause by unequal water pressure as bow passes through successive waves

A

Panting

131
Q

The effect is particularly evident at the bows as the ship pushes its way through the water.

A

Panting

132
Q

refers to the ability for the body to move freely in that particular motion.

A

degree of freedom

133
Q

These six freedoms are divided into two categories

A

three translational degrees, and three rotational degrees

134
Q

three translational degrees arising out of ship motions

A

heaving, swaying, surging

135
Q

The forward and aft linear motion(along x) of a ship is called

A

surging

136
Q

he vertical up and down linear motion (along y) of a ship is called

A

heaving

137
Q

The side to side linear motion(along z) of a ship is called

A

swaying

138
Q

The rotational motion of a ship about longitudinal axis is called

A

rolling

139
Q

The rotational motion of a ship about vertical axis is called

A

yawing

140
Q

The rotational motion of a ship about transverse axis is called

A

Pitching

141
Q

when a materials bent and it can with stand that bending without getting fractured, it is known as a

A

tough material

142
Q

It requires a lot of cycles of bending before the material actually fails

A

Toughness

143
Q

this refers to the property of the material to get deformed before it actually fails due to tension

A

Ductility

144
Q

This property is dependent on temperature and decreases with rise in temperature

A

Ductility

145
Q

a material tends to crack under compression or when its shape is changed due to operations such as extrusion, forging and so forth

A

Malleability

146
Q

increases with temperature as against ductility which follow the reverse trend

A

malleability of a metal

147
Q

also known as join ability, of a material refers to its ability to be welded

A

weldability

148
Q

weldability, also known as

A

joinability

149
Q

are also very critical to it’s over all strength , durability and toughness

A

welds

150
Q

is the ability of a material to absorb energy and plastically deform without fracturing

A

Toughness

151
Q

is the amount of energy per unit volume that a material can absorb before rupturing

A

material toughness

152
Q

refers to the breakdown or degradation of metallic materials due to an electrochemical reaction when the surrounding environment

A

Marine corrosion

153
Q

is defined as the ability of a material to resist plastic deformation, usually by indentation.

A

Hardness

154
Q

The term hardness may also refer to resistance to:

A

Scratching, Abrasion, Cutting, Penetration

155
Q

is the maximum stress that a material can withstand while being stretched or pulled

A

Ultimate tensile strength(UTS)

156
Q

are a large family of metals. All of them are alloys in which iron is mixed with carbon and other elements.

A

Steels

157
Q

are described as mild, medium- or high-carbon steels

A

Steels

158
Q

is the construction of ships and other floating vessels. It normally takes place in a specialized facility known as a shipyard

A

Shipbuilding

159
Q

follow a specialized occupation that traces its roots to before recorded history

A

Shipbuilders, also called shipwrights

160
Q

is the most common material.It is to meet rather strict requirements: strength, flexibility, high manufacturability, weldability, cost, reparability, etc

A

Shipbuilding steel

161
Q

is commonly used for plates of main deck, corrugation bulkhead, collision bulkhead, sheer strake, double-bottom tank top, cross deck etc.These are areas subjected to high stresses which ordinary strength steel cannot support

A

High tensile steel

162
Q

was used in the deck and bottom structure, but lately it has also been used in side-structure and transverse element

A

High tensile steel

163
Q

is defined as the load put on a piece of material or a structure.

A

Stress

164
Q

is defined as the permanent deformity or weakness caused by excessive stress

A

Strain

165
Q

A measure of the ability of a material to withstand a longitudinal stress, expressed as the greatest stress that the material can stand without breaking

A

TENSILE STRENGTH

166
Q

The widest point and the width of the vessel is the

A

BEAM

167
Q

Is a force which tend to break or shear a beam across (perpendicular to} its major axis.

A

SHEAR FORCE

168
Q

It is the total moment tending to alter the shape of the beam

A

BENDING MOMENT

169
Q

When the ship’s end are supported by the crest of a wave known

A

SAGGING or positive bending

170
Q

When the ship is riding the crest of a wave at its midships the bending moment is known as

A

HOGGING or negative bending

171
Q

When ship is floating at rest in still water is called

A

STATIC FORCE

172
Q

The 2 major forces acting on static force is

A

weight of the ship acting vertically down and buoyancy acting up.

173
Q

A pressure acted by the fluid at hydrostatic equilibrium on the contact surface due to gravity is

A

HYDROSTATIC PRESSURE

174
Q

There are six freedom divided into 2 categories; Give two translational ship motion?

A

heaving, swaying and surging.

175
Q

shown as a horizontal line

A

latitude

176
Q

shown as a vertical line;

A

longitude

First Semester (BSMT) (22 decks)

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