Brainscape's Knowledge GenomeTM

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


See full index

ME-175-22-03 > Lub oil and transmission theory 2 > Flashcards

Lub oil and transmission theory 2 Flashcards

1
Q

what are the two main uses of a gearbox?

A
  1. to change the speed of rotation from the prime mover
  2. to change direction of the rotation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is the max ratio limit for a single gear reduction?

A

15:1

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

what is a pinion?

A

the gear that is driving.

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

what is a wheel?

A

the gear being driven.

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

what is the advantage of a dual tandem gear reduction ?

A

halves the load so smaller pinions can be used

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

why are quill shafts important?

A

to flex with the gears to counteract flexing of the boat which would cause de-meshing of gears.

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

what are the 3 ancillaries of a gearbox?

A

Shaft brake
thrust block
turning gear

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

what is a straight spur gear?

A

the teeth area parallel to the shaft it rotates on.
used in low speed applications as they are single contact gears so make lots of noise.

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

what is a helical gear?

A

the teeth are at a angle to the shaft allowing for multiple teeth contact making the stronger and quitter but the teeth push the gears away creating friction.

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

why do we need thrust bearing with helical gear

A

to prevent the gears moving which causes friction.

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

what problem does double helical gears fix?

A

they remove the need for thrust bearings as they are counteract the thrust of the other side of the gear.

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

why do we use worm wheels and some of the characteristics?

A

they allow driving of shafts at 90 degrees to each other
high gear reduction
self locking
good for manual turning gears

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

what pressure does the pressure switch kick in at and when is it tested?

A

18.5psi or less
and tested every 24hrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the job of the serckstat?

A

to regulate the lubricant temperature.

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

what are the 8 components of a gearbox

A

pinions
wheels
input/ output
casing
thrust bearings
bearings
sump (holds oil)
Shafts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what is the purpose of the shaft brake?

A

to stop the shaft and hold it still

17
Q

what are the checks done on a shaft brake?

A

on application
no fire risk exists
all brake pads are applied
shaft is stationary
on removal
all pads are clear
there are no fire dangers exists
the shaft is rotating

18
Q

what is the purpose of thrust blocks?

A

to absorb any thrust from the shaft when the ship flexes and moves ahead and stern

19
Q

what is the purpose of turning gear?

A

to manual turn the gearbox over for maintenance and to align the shaft for dry docking.

20
Q

what is the purpose of the Plummer block and how is it lubricated?

A

to support the shaft with out absorbing thrust from it. lubricates the shaft and its self using dynamic lubrication(Michell principle)

21
Q

what is dynamic lubrication?

A

the picking up of oil from a sump by having the shaft spin off centre slightly causing a wedge of oil to form

22
Q

what are the purpose of bulkhead glands and how is it lubricated?

A

to maintain a water and air tight seal between compartments
lubricated with grease and grease nipples

23
Q

what is the purpose of the stern seal?

A

to maintain water tight integrity as the shaft passes through the ships hull.
has a emergency inflatable(uses LP air) seal if the main one fails

24
Q

what is the purpose of the A brackets and how is it lubricated?

A

to support the shaft out side of the hull
have a main and intermediate bracket
lubricated using seawater (hydrodynamic lubrication)

25
Q

what are the 3 sections of a shaft?

A

thrust shaft (links gear box to the intermediate shaft)
intermediate shaft
tail shaft

26
Q

how is the thrust shaft connected to the intermediate shaft?

A

using flanges, nuts and bolts

27
Q

what is the purpose of the SKF coupling?

A

used to connect the intermediate shaft and tail shaft
consist of a inner and outer sleeve that use a interference fit to hold the shaft and is then fully seated with high pressure oil.

28
Q

what are the two difference types of propeller?

A

fixed propeller
controllable pitch propeller

29
Q

what are the parts of the Plummer block?

A

a casing
dipstick (not Hallie’s)
journal pads
oil cooler

ME-175-22-03 (15 decks)

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