Turning 316L tubing

[Mark VIII]

Has anyone ever turned this material before? We are using 55 deg boring inserts with a .0312 nose radius. Inserts keep blowing out. Tip breaks off. We have run the range on feeds speeds and depths with no luck. 

[Goldorak]

your geometry is ok but for stainless you need the good insert with the appropriate coating and the speed and feed need to be on the spot

 

tell us what you actually use to get some usable information 

[Mark VIII]

Kennametal KCP10 grade dcmt3252LF

DOC varied .01-.05

Feed varied .006-.017

sfpm varied 300-800

 

Before that we tried Kennametal dnmg432rn grade KCP25B

 

 

 

 

[Goldorak]

We cut a lot of 316 (nearly 50% of our production)

A few weeks ago we test the SECO CNMG432-MF4 CP2500 with success, 350-400 SFM .012 IPR and .15 DOC was the sweet spot on our Okuma Crown

unfortunately we never had any success with Kenna ISO turn inserts no matter the shape or the grade we have tested, surprisingly, they beat everyone in milling application for this material ...  

 

Iscar and Sumitomo makes pretty good inserts too for stainless but SECO can go a bit faster for approximately the same tool life ans price 

[Colin Gilchrist]

When you look at a MFG's insert designation, pay attention to the letters after the insert size numbers.

CNMG432-MF

The first letter "M" in the -MF designates that the primary material this insert is designed for is Stainless Steel. The 2nd letter will be R, M, or F. Which stands for the primary type of Operation (Rough, Medium, or Finish). So in general, -MF would be for Stainless Finishing. -MM should be a Stainless Medium operation. And -MR would be stainless  roughing.

[Orvie]

316L.pdf

[Mark VIII]

Thanks for the help guys!