Fiat 480 rear axle tube in SG (ductile) iron
Fiat 480 tractor
A large load-bearing housing that carries the rear axle shaft from the final drive out to the wheel.
- Material
- SG (ductile) iron
- Process
- Sand casting with cores
- Machining
- Flange face and spigot turned, bolt-circle holes drilled
- Finish
- Red primer, machined faces bare
About this part
This part takes the weight of the tractor and whatever it is pulling, which is why we pour it in SG iron rather than gray iron: the spheroidal graphite gives the toughness a shock-loaded housing needs. The bolting flange and its spigot are turned so the tube sits square on the transmission, because a flange that is out of true will load the axle shaft unevenly for the rest of its life.
How we make it
- Sand cast with cores in SG (ductile) iron
- Flange face and spigot turned to register
- Bolt-circle holes drilled, bosses tapped
- Dimensional and visual checks; laboratory testing arranged outside when a drawing calls for it
- Finished in red primer, machined faces bare
Why SG iron and not gray iron?
Gray iron damps vibration well but cracks under shock load. An axle housing carries the machine and the implement, so it needs the strength and toughness of SG iron.
Can you make the same tube for a different tractor?
Yes, from a sample or a drawing. Axle housings differ between models, so the pattern is made for yours.
