Summary Of Results
- Replaced grinding with burnishing
- 30 minutes saved per part
- 6-8 Ra microinch (0.16-0.20 Ra) achieved
THE CHALLENGE
A customer of ours was manufacturing gate valve stems made of Inconel alloy 718 using a Takisawa CNC Lathe. The valve stems were 11.81” (300mm) long, had a diameter of 1” (25.527mm), and required a finish of 16 Ra microinch (0.4 Ra) or better on the main diameter of the stem.
Before contacting us, they had to transfer the part to a CNC grinding machine to achieve the required surface finish which was very time consuming.
Turning Operation prior to burnishing:
- Speed: 450 RPM
- Feed: 0.004”/rev (0.1mm/rev)
- Finish achieved: 48 Ra microinch (1.2 Ra)
OUR SOLUTION
After we assessed their operation, we suggested they use a S2327-00M Single Roll Burnishing Tool made by Elliott Tool Technologies. Here were the statistics after using this burnishing tool:
- Speed: 450 RPM
- Feed: 0.002”/rev (0.05mm/rev)
- Radial load: 0.04” (1mm)
- Finish achieved: 6-8 Ra microinch (0.16-0.20 Ra)