Material starting form for stub axle

[Saints-94]

I am unsure whether I am posting in the right place, but was hoping someone could help me out.

I was wondering if anyone knows the shape of the material at the beginning of the manufacturing process of a stub axle, and how the shape will vary depending on the quantity of products being made (eg. one off, small batch and mass production). Only looking for basic ideas, nothing too in-depth.

See image of stub axle below.

 

[Nidum]

Machined from solid . Usually from long lengths of close to size plain bar .
Machined from forging . Very close to final shape and size - minimal metal removal to finish .
Machined from steel casting . Same as forging .

 

[Saints-94]

Machined from solid . Usually from long lengths of close to size plain bar .
Machined from forging . Very close to final shape and size - minimal metal removal to finish .
Machined from steel casting . Same as forging .

Thanks for your response.

However, I have been advised that cast form is inapproriate due to its high structural integrity. Are there any alternatives?

 

[Nidum]

However, I have been advised that cast form is inapproriate due to its high structural integrity.

Not quite sure what you are saying there - can you explain a bit more ?

There are certainly other ways to make stub axles and similar components .

One that works well but is seldom used in production is the two part assembly where the actual axle is friction welded to the flange .

What is your interest in this subject ?

 

[BvU]

However, I have been advised that cast form is inappropriate due to its high structural integrity. Are there any alternatives?

You mean the device needs to be stronger than cast iron ? (or do you mean that cast form has high structural integrity which you don't want )

The thing resembles a bolt - so http://blog.mechguru.com/machine-design/7-steps-manufacturing-process-bolts-screws-stud-fasteners/ is where I'd look.

 

[Baluncore]

For quantity production.
For maximum strength to weight ratio, a stub axle needs to be forged from steel. Forging will allow the stretched fibres in the steel to follow the lines that will carry load when in operation. You could start with a short round bar. Upset or spread one end to make the flange, while thinning and lengthening the shaft. Once the basic shape has been formed it will need to be annealed to relieve stress and hard spots, then machined and finally surface hardened.

For small quantity production it could be turned from a rectangular block of steel in a lathe. That would be slow and wasteful.

You might also consider fabricating it from a flat square block with the round bar pressed into a central through hole. The bar would then be welded on the back of the flat plate with a deep V groove. That would not be the strongest for weight solution as the press fit would be at a stress concentration.

 

[Dr.D]

For small quantities only, you might start with a weldment (short shaft inserted through a block, full penetration weld on all edges) and then machine to final shape.

For larger quantity, a forging is the way to go.