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truck tails shafts lengths 2
- Thread starter alequip
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GregLocock
Automotive
what rpm does it run at the truck's maximum speed?
what material is it made from?
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376
what material is it made from?
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376
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- #3
LionelHutz
Electrical
A drive shaft will turn into a skipping rope as it reaches a critial rpm. I've seen the formulas for calculating the rpm on the internet before. Try a Google search.
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2
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GregLocock
Automotive
It is not as simple as that. The skipping rope shape is longer than just the distance between the UJs and the inertia of the driveshaft is greater than just the tube because of the mass of the UJs.
So, yes, you will be able to find an equation for the critical speed of a shaft on the internet, but if it hasn't been adjusted to take those two effects into account then it will be misleading, and will overprdict the safe rpm.
I would suggest looking at a book that discusses driveshafts explicitly, a power transmission specialist may have one, the SAE certainly had a driveline manual, but I can't remember if it includes whirl speeds.
You also need to make sure that you run at significantly less than the critical speed, as the resonant peak has shoulders. I'd suggest 30% would be a good starting point.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376
So, yes, you will be able to find an equation for the critical speed of a shaft on the internet, but if it hasn't been adjusted to take those two effects into account then it will be misleading, and will overprdict the safe rpm.
I would suggest looking at a book that discusses driveshafts explicitly, a power transmission specialist may have one, the SAE certainly had a driveline manual, but I can't remember if it includes whirl speeds.
You also need to make sure that you run at significantly less than the critical speed, as the resonant peak has shoulders. I'd suggest 30% would be a good starting point.
Cheers
Greg Locock
New here? Try reading these, they might help FAQ731-376
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