1. A Study of Fixture Layout and Clamping Force for a Ti-6Al-4V Disk in a Vertical Turning Lathe Numerically Controlled Machine Maureen Fang Sept 17, 2009

2. Overview Vertical Turning Lathe (VTL) Machine Fixture-Disk Assembly Cutting Forces Finite Element Models in ANSYS Initial Fixture Layout Deflections within Disk Questions

3. Vertical Turning Lathe (VTL) Machine

4. Fixture-Disk Assembly Clamp Plate Disk Inner Diameter=0.457m (18 in) Outer Diameter=0.508m (20 in) Height=0.0508m (2 in) Locator

5. Machining an Outer Diameter Cutting Tool

6. Cutting Forces Orientations

7. Cutting forces calculation Flow Diagram

8. Input Variables Tool Geometry Machining Parameters

9. Cutting Forces Results are generated by Matlab codes for both oblique and orthogonal cutting Orthogonal cutting has only two cutting forces components Tangential force is the dominate component. Tangential Force Orthogonal Cutting

10. Finite Element Model in ANSYS Number of elements32000 Number of Nodes38720 Degree of Freedom per Node6 Type of ElementsBrick Material of Workpiece Ti-6Al- 4V Modulus of Elasticity110 GPa Poisson Ratio0.34

11. Deflections during a complete cut The “U” shape curve presents the magnitude of deflection changes as the cutting tool travels from the top to the bottom surface of the disk. The displacement vector sum is largest at the top. The subsequent models will have the cutting forces applied at the top surface.

12. Initial Fixture Layout

13. Circumferential locations Circumferential locations of one set of clamp and locator with respect to cutting forces

14. Displacement Vector Sum A B C

15. Displacement Components Z-component = axial direction Y-component = circumferential direction

16. Contour Plots from ANSYS

17. Questions