Straightening for Rings post heat treatment

[alliedtrans]

Hello

I have a component with OD 228.7 mm with material composition EN 15. We heat treated it in a salt bath furnace with marquenching to achieve a hardness of 53. Now we are in a big fix as the OD distortion is more than 1mm and we have tried straightening with a ring type fixture and using a hammer on the point of distortion as well with no result.

Is there any way I can reduce the distortion to 0.1mm which is acceptable to us as there is a grinding process left.

We routinely straighten 20MnCr5 using ring type fixtures but this component has a smaller wall thickness and bigger OD.


Please Help!

 

[gearcutter]

Unfortunately there isn't a whole lot that can be done at this point of the process.
Only 1mm of distortion on a part that size and geometry is a pretty good result.
It's a very common problem that requires precise control of the manufacturing process, from start to finish. Even then, there isn't any one technique that will guarantee a distortion free part.
The best way of helping get repeatability of parts is by using a quenching press or by allowing enough material be left for a post-temper finish machining operation.


Ron Volmershausen
Brunkerville Engineering
Newcastle Australia

http://www.aussieweb.com.au/email.aspx?id=1194181