Cause of the ring climbing and how to solve it.


1. Cause of the ring climbing
There are some reasons for the ring’s climbing up and down(Rippling).
In this case the bad shape of the preform is the main cause of the ring’s rippling.
I explained the process of making preform at my blog before.
The process of making preform is cogging→upsetting→punching→piercing as I explained at that post.
When you press the punch too much and don’t make the preform flat, you will have this bad shape of preform.


When the axial roll press down the preform, the other side of the preform will go up. It’s not easy to make the ring stable if this happened.
2. Result of the ring climbing
You can see a gap between the stacked rings. And you need to add more excess material for the ring. It makes the ring expensive

3. How to solve this problem
If you have to press the punch deeply to save the material, you have to make the preform flat after piercing it.
The quality of the preform is very important. It affects the quality of the ring product.
I always emphasize the importance of the preform quality to the press worker.
If you’ve made this bad shape of preform already and you don’t have time to modify it and roll it, I recommend that you’d better turn the preform upside down.
 

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