Test 3 Flashcards
(136 cards)
1
Q
What is the formula for safe working load?
A
Breaking strain divided by safety factor
2
Q
Where is the safe working load marked on a crane?
A
On the heel of the boom.
3
Q
How often is cargo gear surveyed or recertified?
A
Surveyed every five years, and re-certified annually
4
Q
What are the three motions of pedestal cranes?
A
Slew, luff, hoist
5
Q
What does a runner/whip do?
A
Controls the vertical position of the load
6
Q
What does a topping lift do?
A
Controls the height of a conventional (yard and stay) boom
7
Q
What does a luffing wire do?
A
Controls the height of the pedestal crane boom
8
Q
What is slewing?
A
The motion of a pedestal crane rotating at the base
9
Q
What is luffing?
A
The motion of a pedestal crane in which the boom itself moves up and down
10
Q
What is hoisting?
A
The motion of the cable or wire actually raising the load
11
Q
What is “out reach” referred to as in regards to US Coast Guard license questions?
A
Load radius
12
Q
How is slewing accomplished on a pedestal crane?
A
By ring gear and slewing motors.
13
Q
What are the three types of slewing cranes?
A
Conventional, low type, heavy lift.
14
Q
What’s the difference between a conventional and low type crane?
A
A conventional crane boom is raised by luffing wire, and low type crane boom is raised by hydraulic cylinders.
15
Q
What is level luffing?
A
Raising or lowering the boom without appreciable rise or fall of the cargo hook.
16
Q
When is level luffing most important?
A
When the careful movement of a load near ground level is required.
17
Q
What two instances Can level luffing not be achieved?
A
With conventional yard and stay cargo gear, or low type pedestal crane
18
Q
What is the safety factor of cargo gear?
A
Five
19
Q
What happens when a boom or crane is lowered?
A
Out reach increases, and the SWL decreases
20
Q
What are the factors affecting cargo gear selection in a vessel design?
A
Preferences of potential charters Cargo handling capabilities of anticipated ports of call Likelihood of project cargo bookings Additional weight of cargo gear itself Stability considerations
21
Q
Cargo gear has a high
A
Vertical center of gravity
22
Q
What type of ships carry project cargo?
A
Heavy lift ship’s
23
Q
What is safety factor?
A
The ratio of strength to an expected load
24
Q
Project cargo is
A
Too heavy or large to be carried on conventional cargo ships. Has special carriage requirements
25
What is luffing sometimes referred to as?
Topping the boom
26
What is the average maximum pulling capacity of a drum winch ?
10–25 tons
27
What is the term used to describe when a pedestal crane is secured?
Cradled
28
On a slewing crane what causes brakes to be applied if there’s a loss of power?
A zero voltage device
29
An automatic shut down if any part of the crane experiences overload is a
Overload safety
30
A switch which stops the crane if the hoist is raised too high is a
Hoist limit
31
What stops the crane if less than three wraps are left around the drum?
Empty drum
32
What stops the boom from going to high or low?
Limit switch
33
What kind of cargo is typical for a gantry crane?
Containers or bulkers
34
What are advantages to side loaders?
Minimal impact on stability, more direct cargo movement, cover dock possibilities.
35
What are disadvantages to a side loader?
Hull strength reduction “hull girder”, elevators take space, less weight capability, smaller parcels
36
Who tests and certifies cargo gear?
The classification society
37
What cargo gear is included for testing?
The crane structural assembly, rigging, wire ropes, sheaves, cargo hook, loose gear such as shackles slings and spreaders.
38
What type of material is used for a stopper?
The same type of material as the mooring line, except in the case of wire, we use a chain stopper.
39
While inbound or outbound in pilot waters, and anchor is always
Lowered from the hawse and ready to let go
40
Who typically stands by anchor ready to let go for emergencies?
The chief mate, or a licensed deck officer and a boatswain or AB
41
Holding power comes from
Weight of the anchor and the scope of the chain
42
What kind of anchors are mostly used on seagoing vessels?
Stockless
43
The scope of a chain is usually
5 to 7 times the depth of the water
44
Where must a ship be positioned when heaving an anchor?
Directly over the anchor
45
What is SOG?
Speed over the ground
46
What is the term used to describe the anchor secured into the Haus pipe?
Anchors home
47
What is located in the Haus pipe to remove mud?
Water washdown jets
48
A machine used to handle anchors and typically has drums for mooring line handling is known as a
Windlass
49
A drum on a windlass is referred to as a
Gypsy head
50
A deeply grooved drum on the winless with sprockets and pockets which engage the links of the anchor chain is the
Wildcat
51
What prevents a chain from fouling on the wildcat
A stripping bar
52
A capstain head, drum or gypsy head are all
Drums fitted to the windless
53
A riding Pawl is a
One way device when set
54
When a pawl is down
The chain cannot pay out but can be heaved in
55
When is the only time a riding pawl will be raised?
When the anchor is dropped or lowered
56
A shot of chain is equal to
15 fathoms or 90 feet
57
Arranging a mooring line on deck in long bites with half turns at the ends of the bites is known as
Faking
58
What’s the largest non cargo space aboard ship?
Engine room
59
What are the the cycles in order on a four stroke?
Intake
Compression/ignition
Power/expansion
Exhaust
60
When does combustion occur?
At TDC
61
What type of ignition is diesel?
Compression
62
What type of ignition is gas?
Spark
63
Ic engines aboard ship are usually started with
Compressed air, hydraulics or electric
64
Main engines and generators are started with
Air
65
Emergency generators may be started by
Hydraulic or battery power
66
Classification societies require enough air capacity for
12 starts, including reversals
67
Right handed propellers produce forward thrust when turning
Clockwise
68
Left handed propellers produce forward thrust when turning
Counter clockwise
69
The distance a propeller will advance in one revolution
Pitch
70
Units of pitch
Feet
71
Pitch is determined by
Angle formed by blade and axis of hub
72
The least refined fuel oil is
HFO- heavy fuel oil
73
Marine diesel oil is
More refined than HFO and has a lower viscosity
74
What is the cleanest fuel?
Natural gas
75
What type of fuel is not used for large engines?
Gasoline
76
What are the requirements of MARPOL Annex VI?
EST emission control areas
Worldwide limits on NOx and SOx
EST preclusions for deliberate emissions of ozone depleting substances
EST fuel quality standards (sulphur by content)
Ushered exhaust gas scrubber technology into marine engineering
77
Two types of combustion air
Naturally aspirated
| Supercharged
78
PM=
Particulate matter
79
Emission control areas
```
Mediterranean
Baltic
Black
Red
Gulfs
North
Antarctic s of lat 60
Caribbean
```
80
Where is automation found aboard ship?
```
HVAC
Fuel oil transfer
Bilge
Waste water treatment
Iron mike
```
81
Any change in the magnetic field of a coil of wire will cause an electromagnetic force to be induced into the coil.
Faraday’s first law
82
A device that converts mechanical energy to electrical energy for use in an external circuit
Generator
83
Hydraulic flow ~
Electrical current
84
Hydraulic pressure ~
Electrical voltage
85
Hydraulic resistance ~
Electrical resistance
86
Describe the flow of energy
Fuel to generators to main/aux buss to transformers to loads
87
What’s at various junctions?
Circuit breakers
88
Transformers do what two things?
Step up or down voltage
89
A buss is a
Distribution node
90
What two things do busses do?
Receive energy from generators and distribute to loads
91
What are 5 prominent propulsion modes?
```
Rudder/propeller
Kort nozzle
Azipod- mover in pod
Cycloidal
Z-drive mover in hull
```
92
The comparison of theoretical distance traveled to observed distance traveled is
Propeller slip
93
How do you calculate slip?
1-(observed distance/calculated distance) x 100%
Or
1-(actual travel/pitch travel) x 100%
94
Formation of vapor bubbles (voids) in water near moving propeller is known as
Cavitation
95
A propellers tendency to cause the ship to rotate about the vertical axis at slow speeds ahead or astern is known as
Wheel or walking effect
96
Which direction will a right handed propeller walk a vessel?
Stern to starboard and bow to port
97
When backing, a right hand propeller walks the vessel
Stern to port and bow to starboard
98
Fixed pitch propellers advantages
Less apt to damage
No rotation when no power
Less dangerous for mooring
Less risk of propeller entangled in mooring lines
99
Fixed pitch propeller disadvantages
Too many rpms during adverse weather
| Limited range of rpms for maneuvering and power
100
Controllable pitch propeller advantages
```
Propel at all engine speed
Quick change from ahead/astern
Improve efficiency
Main engine runs at optimum rpm
Easily combined with shaft generator
Stops with max power
Changing one blade is possible
```
101
Controllable pitch disadvantage
```
Vulnerable to damage due to hydraulic components and seals
Oil pollution
Creep at 0 pitch
Unusual handling characteristics
Loss of steering in neutral position
Difficult to repair
Price
Still turns at all stop
```
102
What type of propeller is most likely to foul a mooring line?
Controllable pitch
103
What is a nozzle on a propeller?
The shroud
104
A thrust bearing is designed to
Transmit the thrust of the propeller to the vessel
105
Bow and stern thrusters are
Great at speeds less than 3 kt
Can be a propeller in a fixed transverse tunnel
Can be retractable or swiveling
Can be cycloidal
106
The perfect propulsion system for precise maneuvering even under adverse conditions
Vogt-Schneider cycloidal propulsion
107
The VSP magnitude and direction of thrust is
Infinitely variable
108
With VSP the magnitude of thrust is determined by the
Rotational speed of the disk
109
With VSP the direction of thrust is determined by the
Blade angle
110
Stabilizers can reduce rolling up to
80-90%
111
What on a ship utilizes faradays law?
Shipboard generators
112
Phases for dc power
None
113
Phases for ac power
Single and 3
114
Dc power is found
In nature
Ie static electricity
Lightning
115
Dc current can be produced by
Battery-and stores
Dc generators
Fuel cell
Solar cell
116
Dc is preferable for
Emergency lighting and winch motors
117
Can we utilize static electricity?
No
118
Which current is used for most power loads?
Ac
119
All electrical generators produce
Ac current
120
The rate at which the polarity is reversed is called
Frequency
121
Frequency=
(#poles x rpm) divided by 60
122
Frequency is determined by
Speed and construction of the generator
123
Common shipboard frequency
```
60 Hz (U.S)
50 Hz (Europe)
```
124
Essentially, three single phase generators have been placed in one machine
3 phase ac
125
Which phase is common for machinery?
3
126
Which phase is common for lights and electronics?
Single
127
Advantages to 3 phase
```
Universally for transmission of ac
Higher power to weight ratio of alternators
Cheaper
Less line to transmit
Self starting
Instantaneous power is steadier
Better power factor
Less ripple effect when rectified into ac
```
128
UPS
Uninterrupted power supply
129
Ups consists of a
Battery, battery charger, and inverter to convert dc to ac.
130
A ups provides
Temporary electrical power in case of main power disruption
131
An emergency generator is typically a
Small diesel generator
132
Main components in ships electrical power system
```
Fuel
Heat
Generators
Electrical busses
Transformers
Circuit breaker
Loads
```
133
Reverse power relays
Prevent generators from becoming motorized if one fails
134
Name three electrical protection devices
Fuses circuit breakers and reverse power relays
135
Dc frequency =
0
136
Typical ac loads on ship
```
HVAC
Bridge electronics
Accommodations
Lighting
3 phase motors
```
