Driveshaft/halfshaft design 1

[amorrison]

General question.

Why are driveshafts/halfshafts engineered the way they are?

Say for a 100-200hp vehicle(2wd or 4wd)the driveshaft to the rear diff is ~1.5inch in diameter and hollow while the halfshafts to the front wheels of a 2wd are ~3/4 inch in diameter and solid. The larger hollow shaft has less torque load than the smaller diameter hahfshafts.

Length?,wrapup?,material?,rotational jerk(impact loads)?

 

[MikeHalloran]

Critical speed.


Mike Halloran
Pembroke Pines, FL, USA

 

[GregLocock]

incidentally both your estimated ODs are very small, I'm more used to numbers like 2 1/2 (for a two piece) and 1 1/4 respectively.

Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.

 

[amorrison]

Thankyou Greg.

I was hoping a guy like you would also answer the gist of the question. (;<))

Regards

 

[GregLocock]

Mike's point was entirely right, propshafts are (often) designed for whirl, halfshafts for torque capacity. Halfshafts are often made from the well titled axle-steel, whereas you can make propshafts from aluminium, steel, MMC or carbon fibre, and no doubt there are other examples.


Cheers

Greg Locock

SIGlease see FAQ731-376 for tips on how to make the best use of Eng-Tips.