Transmissions Flashcards
Gearbox ancillaries
Shaft brake
Thrust block
Turning gear
What are plumber blocks used for?
Plumber blocks are used to support the weight of the shaft within the ship without absorbing any thrust
What are plumber blocks made of ?
Michelle white metal
When is the plumber block affective after?
Effective after 50 RPM
What does a serkstat do?
Ensures the oil is kept at optimum temperature by allowing the oil through the heat exchanger
Too hot = too thin
Too cold = too thick
Shaft break checks?
Ensure no fire risks are present
All break pads are applied
The shaft is stationary
After removal
All pads are disengaged no fire danger exists
The shaft is turning
When can the shaft break be applied?
When the engine is at idle speed
What type of gear teeth are there?
Straight spur
Helical
Double helical
Worm wheel
What is the use of the transmission/ gearbox ?
Transit power from the prime mover to the shaft
Allow for variations in speed and power
Allow change in ahead and astern thrust
What is the max reduction in the RN ?
15:1 step down
What is the thrust block?
Designed to absorb the force generated up the shaft due to the action of the propeller
This is situated just after the gearbox
Consists of a color on both sides and fitted with Michelle white metal pads
What is the turning gear used for?
Mounted to the gear case and provides a drive which will slowly turn the shaft so the propellor can get in the correct position for harbour
What is a skf coupling
So The tail shaft can be removed with out taking the whole shaft out
What is a quill shaft
A thin solid shaft machines so it will take the same torque that a large shaft would take
Acts like a torsion bar twisting across its length
Bulk head gland
To maintain water tight integrity as the shaft passes through the compartment
Designed to be flexible to distortion because of damage occurring from collisions
