This is how turbo turbine shaft wheel’s grooves are machined?
Typically, every turbo turbine wheel shaft will have a one or two grooves on the shaft.
One is for oil slinger groove.
The other is where pistion rings go into, sealing the engine oil inside turbo CHRA/core from leaking out into turbine housing/side.
Robot picking and retrieving turbine wheel shafts for machining
How is turbo turbine wheel made?
Face milling stainless steel turbo turbine housing inlet flange