Power Transmission Review Flashcards
The LEAD and the PITCH of a WORM are the same when:
If it has a single start
In what shaft positions are the cross dial sweep readings taken and recorded?
In four planes at 12, 3, 6, and 9 o’clock
When checking backlash you should place the dial indicator button on the worm wheel tooth:
At the pitch line
If the input power is on the sun gear and the carrier is locked to the sun, the output will be a forward reduction?
False (Reverse low)
Driver: Sun, Driven: Carrier, Held, Ring. Final Output?
Reduction (low)
Driver: Sun, Driven: Ring, Held, Carrier. Final Output?
Reverse (low)
Driver: Carrier, Driven: Ring, Held, Sun. Final Output?
Overdrive (normal)
Driver: Carrier, Driven: Sun, Held, Ring. Final Output?
Overdrive (high)
Driver: Ring, Driven: Carrier, Held, Sun. Final Output?
Reduction
Driver: Ring, Driven: Sun, Held, Carrier. Final Output?
Reverse (overdrive)
Driver, Driven and held. Two members are locked together
Direct drive
In a planetary system if none of the planetary members are held, what is the result of the Final output?
Neutral
One advantage when using the cross dial method is?
It eliminates error caused by axial float
TorF. The pinion gear is usually the smallest gear in the set.
True
Which dialing alignment procedure has concerns with shaft end float error?
Rim and face alignment
Why is a good mesh pattern important to the life of a gearbox?
So that there is even distribution of load on the teeth
When performing CROSS DIAL alignment, the distance between dial indicators should never be less than:
4”
The backlash setting in worm and worm wheel reducers that frequently start, stop and reverse should be?
A minimum value
How much backlash should there be between spur gears with a diametral pitch of 8?
0.005” Backlash=0.040/DP
In a speed increasing gearbox: Output speed (Increases or Decreases) and output Torque (increases or decreases)
Output speed increases, output torque decreases
When checking for coupling rim runout, the high spot on the rim causes the dial to:
Move to a positive value
What are shims used for in a gearbox?
To adjust mesh pattern and end float
When single helical gears mesh, the thrust developed in a driven gear in relation to the thrust developed in the drive gear is always in which direction. (Direction and plane (axial or radial))
Opposite direction axially
Gear tooth clearance can be mathematically worked out by the following.
Whole depth-working depth
Why is residual magnetism dangerous to rebuilt gearboxes?
Attracts iron particles to wear surfaces
Before a precise alignment is started, the machines should be roughly lined up horizontally within how close of true position.
10 mils (0.25mm)
TorF. A drive using helical gears can have the gears set up for the are overhung
True
Before starting to take a set of cross dial sweep readings it is suggested that: (Where to zero the A and B Dials)
“A” be zeroed at the top and B at the bottom
Overhauled gearboxes should be fitted with magnetic drain plugs and
Visual oil sight glasses
Two gears will only MESH if they have the SAME:
Diametral pitch
Rim dial runout readings are taken with the dial button reading on
Rotated rim
A SUN gear is one of the components of a _______ gear set?
Planetary
Hold-down bolts can be necked down to:
?????
What type of gear is conical in shape (Cone shaped)
Bevel
In order to have accurate FACE READINGS, it is very important to arrest:
Axial Float
TorF. A gearbox has a 10:1 reduction by a 1 hp electric motor at 1750 RPM. The output from the gearbox will be 10 hp at a speed of about 175 rpm.
False (HP is constant)