Two piece gear designs

[Brusco]

Where can I find data regarding durability data for two piece gear designs with impact/shock loading?

 

[unclesyd]

Need more information as to the type, size, material, power,
etc.

 

[Brusco]

25 degree PA, 1.0 module, 52mm gear, 20mm pinion, 8620, carburized, 144 Watts (0.20 Hp)

 

[Carburize]

What exactly do you mean by "two piece"?
1)Split in half across a diameter to produce two half gears which are somehow fastened back together in the style used for example on large kiln drives?
or
2)Split through the apex of a double helical?

 

[Brusco]

The gear will have a ID through which the pinion will be pressed into. The press interface will not have any gear teeth and we are looking into a 20-50 micron intereference on a 14mm diameter.

They are both spur gears.

 

[Carburize]

Like my example 2 but spur gears??

 

[Brusco]

Exactly.

 

[scarecrow55]

you could treat the stresses as the thick cylinder theory, I would think any excess torques would seize the parts together anyway

 

[diamondjim]

I think if the gears were stacked together
when cut and then their relationship
ensured by pinning, then you could treat the
gear assembly as one gear. If not, you would
have to derate it by the obviously mismatch
that would occur during the mesh cycle.
If you lined up the high points of each gear
it would be of some help. I assume the gears
will be bolted together and have locating
pins around the bolt circle. Just curious
why the gears were split if it is like
case 2 as carburize suggests and not 2 half
circles.

 

[Carburize]

As others have indicated the big issue will be alignment, if you can key the parts it may be possible to produce a set with the required accuracy, though as diamondjim asked -why is it necessary to introduce this degree of complication for a spur gear?

 

[Brusco]

Well, the 20-50 micron press gives me a safety factor of 35 for static loading, my concern is more the impact loading and doing analyzing dynamic loading effects on the interface. We currently have no plans to key or pin the interface.