best way to manufacture tapered tubes? 1

[tronics21]

Hi,
I am working for a small engineering company with less with 20 employees.

We are trying to manufacture a some number(~5000pc) of tapered tubes(~10" length) in China.
They are going to be either stainless steel or aluminium. We haven't decided which way is the best.

I was thinking about die casting aluminium tapered tubes and anodizing them
but soon realized that cast aluminium cannot be anodized due to high silicon contents.

Now I am looking for alternative options. Maybe we are going to power coat cast aluminium tubes or use stainless steel.
I am not sure which way is the best to go...

I cannot tell you exactly what they are going to be used for but tapered tubes are going to be fit in each other like those plastic cups.
Can anyone give me any advice on this matter?

Thank you!

 

[BillPSU]

It is quite interesting that you have decided that China will make the part yet you have no clue on how to make the part and what equipment is required. Ask your China company for help.

 

[ornerynorsk]

Swaging or some variant thereof. As one who sources "a lot" of components both locally and offshare, let me share a word of caution with you. China is wonderful at duplicating parts, and manufacturing very straightforward parts. If you are still in the experimental stage, don't know the material, don't know the process, and haven't thought through the consequences and contingencies of a project gone awry, you may want to do some homework first, BEFORE contacting a Chinese vendor.

You will be told that yes, they can do it, no problem. This is SOP with Chinese companies. 8 months later you'll be cursing them and cursing yourself for not doing a little more due diligence. I have some top notch work done in China, don't get me wrong, but you need to be able to specify and verify every aspect of your component in the process.

It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.

 

[hendersdc]

Hydroforming could be a good option for you.

Doug

 

[KENAT]

There may be ways to anodize the cast aluminum depending on various factors but yes can be tricky.

What kind of dimensions are these 'tubes'? I assume fairly thick walled if you're considering casting them.

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