Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Mech Theory 4 > Mech Theory 4 > Flashcards

Mech Theory 4 Flashcards

1
Q

What are the energy statements for boiling liquids

A

As pressure increases, volume decreases and more energy is needed to boil a liquid

As pressure decreases, volume increases and less energy is required to boil a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Three ways heat can be transferred

A

Convection
Conduction
Radiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Sensible heat

A

Heat required to change temperature but not state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Latent heat

A

Heat required to change the state but not temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Super heat

A

When the temperature goes above the boiling point

Every degree of temperature above then gains 1 degree of superheat
For example 101c = 1c of superheat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define sub cooling

A

When a substance cools and condences into liquid and drops below its boiling point it is sub cooled, for every degree below its boilling point it gains one degree of super cooling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name the four components in the 4 part refrigiration cycle

A

Compressor
Condensor
Thermal expansion valve (TEV)
Evaporator

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

TEV?

A

Thermal expansion valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does the compressor do

A

Pumps the refrigerant around the system and raises the temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does the condenser do

A

Uses sea water to cool the refrigirant to change its state from a gas into a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does the thermal expansion valve do

A

Used to slow the rate of the refrigerant flow and lowers the pressure and temperature of the liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What does the evaporator do

A

Very cold liquid enters the evaporator and changes the liquid into a gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the uses of water

A
  • Drinking
  • Washing
  • Cooking
  • Cleaning
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the methods of defrosting

A

Natural defrosting
Hot gas defrosting
Electrical heating coils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the methods of leak detection

A 
Oil slicks 
IRLDS (Infra red leak detection)
Spectrolyne dye and UV lamp
Snoop
Halogen leak detector
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

3 types of fridges

A

Freezers
Walk in veg stores
Ready to use fridge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Montreal summit

A

To reduce ozone damaging gases
CFC
HCFC
Halon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Kyoto summit

A

To reduce green house gases
HFC
PFC
CO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Hydroscopic?

A

Absorbs water from the atmosphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Three types of refrigerant oil

A

OM70
Suniso 3GS
SW 68

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Methods of topping up oil

A

Sump filling plug
Hand pump
Dazing pot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What colour is the fresh water hose and what should you do before connecting it to the ship

A

BLUE

clean the hose by flushing it out with fresh water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

When are chlorine leaks checked

A

Daily

Before embarking

24
Q

Why must chlorine be added to the water tank and NOT during reverse osmosis procedure

A

Because it can cause irreversible damage to the membrane

25
Q

Types of filters

A 
Panel filters 
Supply filters 
Grease filters 
Lint filters 
Dust filters 
Flameproof gauzes
26
Q

Special areas with ventilation requirements

A 
Galleys 
Store rooms
Auxiliary machinery spaces 
Sewage treatment spaces 
Magazines
27
Q

ATU? And what are the % of air it runs at

A

Air Treatment Unit

33% fresh air
67% Re-Circulated air

28
Q

Before entering the refrigeration machinery room you must

A

Inform the rating in charge
No smoking
Breathing apparatus available
Exhaust fans running

29
Q

3 parts of the AFU

A

Pre particulate filter
Particulate filter
Gas filter

30
Q

Pre particulate filter

A

Paper filter which removes course particles

31
Q

Particulate filter

A

Glass fibre filter made to remove bacteria by entrapment

32
Q

Gas filter

A

To remove all known chemical warfare agents

33
Q

When will phosgene gas be created

A

If it is exposed to high temperatures

34
Q

What is given off if fruit and veg decomposes

A

CO2

35
Q

What are the procedures for entering refrigeration compartments

A
  • Exhaust fans running
  • No smoking
  • Inform a senior rate
  • Tag in and out
36
Q

1 major difference of refrigeration and chilled water plant

A

refrigeration has a chiller instead of a evaporator

37
Q

What are the uses of ventilation

A
  • electronic equipment

- galley ventilation

38
Q

Condition of refrigerant as it flows through each compartment

A

HOT-WARM-VERY COLD- COOL

HIGH PRESSURE X2-LOW PRESSURE X2

GAS-LIQUID-LIQUID-GAS

39
Q

4 refrigeration hazards

A
  • Heavier than air, so it displaces oxygen
  • Phosgene gas
  • Frost bite
  • Decomposing fruit and veg (CO2)
40
Q

Types of oil used

A

OX30 RED
OX40 GREEN
OM33 YELLOW/ORANGE

41
Q

Desirable properties of hydraulic oil

A
  • Incompressible
  • Good lubrication
  • Good sealing properties
42
Q

What does Demulsibility mean

A

When the water can be separated from a fluid

43
Q

Why are anti oxidants added to oil

A

To stop sludge and gum

44
Q

List 6 hydraulic pumps

A
  • Integral gearwheel
  • External gearwheel
  • Vane
  • Lobe
  • Radial piston
  • Axial piston
45
Q

Purpose of a drain leg

A

Returns oil that has been used for lubrication, sealing and cooling

46
Q

What does an actuator do

A

Converts hydraulic energy into mechanical motion

47
Q

4 advantages of a hydraulic system over an electric system

A
  • Easily reversible
  • Infinite speed range
  • High torque low speed
  • Reliable
48
Q

State 4 types of filters

A
  • Panel
  • Supply
  • Lint
  • Dust
49
Q

When would a bleed valve be operated

A

If the pressure is more than 2 WG

50
Q

What is a citadel

A

Whole ship shelters from chemical, nuclear and biological warfare and makes it air type

51
Q

Parts of the desalination

A
  • SW inlet
  • Membrane
  • O seal
  • Permeable water
  • Concentrate
52
Q

Type of filter

A

Bag filter 60 MICRONS

53
Q

CCV - concentration control valve

A

Controls the back pressure and of what quality

54
Q

Fresh water tests

A
  • CHEMets
  • Visual
  • Taste
55
Q

What system is hydroscopic referring to

A

Refrigerant oils

56
Q

Refrigerant oils

A
  • OM70
  • Suniso 3GS
  • SW 68
57
Q

Hydraulic oils

A
  • OM30 Red Sub
  • OM33 Yellow T42s
  • OX40 Green T45s

Mech Theory 4 (1 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions