1. EAST MECHANICAL DEPARTMENT
RAPID MANUFACTURING
PROCESS
RAPID MANUFACTURING
PROCESS
BHUBANESWAR,KHURDA

2. PRESENTED BY AMAN KUMAR PANDA
MECHANICAL,GRP –ME1.(A)

3. THE COMMON MACHINE OPERATION
STATIC MACHINE ELEMENT
IN EXTRA ORDINARY SCIENCE

4. Common Machining Operations
Kalpakjian

5. Parts of an “Engine” Lathe
Kalpakjian

6. Typical “Engine” Lathe
Watchmaker’s lathe
Typical “Engine” Lathe
Turret Lathe
Big “Engine” Lathe

7. Really Big “Engine” Lathes
60 feet c-c

8. CNC Lathe: aka “Turning Center”
(carriage is mounted toward back, “upside down”)

9. Machining
Parameters
DeGarmo

10. Machining: Turning Depth of Cut = DOC = (Dbefore – Dafter) / 2
Cutting Speed = Speed of metal moving towards cutting tip
Usually called “Surface Feet per Minute”, SFPM, SFM
Each cutting tool & workpiece material combo has a max SFM for decent tool wear.
HSS & alum: 800 SFM
HSS & 1020 steel: 110 SFM
HSS & 1090 steel: 80 SFM
HSS & hard 4140: 30 SFM
TC & 1020 steel: 1000 SFM
SFM = r*w
= D * RPM * (π/12)
≈ D * RPM / 4
RPMmax = 4 * SFM / D
(most useful machining formula)
E.g., find RPM for turning
2” dia steel:
RPM ≈ 4*110/2 = 220
RPM may need to be less due to chatter!
Most relations are similar
for milling, but D=cutter dia.
Kalpakjian

11. Cutting
Forces
DeGarmo

12. Orthoganal
Model
(2-force)
DeGarmo

13. Orthoganal
Model
(2-force)
DeGarmo

14. Chip formation: chip types
DeGarmo
Kalpakjian

15. Merchant’s Model
(Simplified 2-force)
DeGarmo

16. Chatter
Vibrational resonance of entire machining system, especially workpiece-cutter.
Causes poor surface finish, fast tool wear, noise
Factors: stiffnesses of workpiece, cutter, machine
cutting params: speed, feed, DOC
cutter geometry: rake, clearances
Solutions:
Change the cutting params
esp. speed
Increase stiffnesses
Kalpakjian

17. Heat rise in Cutting
Kalpakjian

18. Temperature of Cutting Tip
Kalpakjian/Vieregge

19. Temperature of Cutting Tip
Kalpakjian / Chao & Trigger

20. Max Temperatures of Cutting Materials
Kalpakjian

21. Machining Time of Cutting Materials
Kalpakjian/Sandvik

22. Coated Carbide Cutting Inserts: The norm for production machining
Layers are 2-10 microns thick:
TiN: titanium nitride (low friction, gold appearance)
TiCN: titanium carbonitride (wear resistance)
Al2O3: Alumina (chemical stability, wear resistance)
Tungsten Carbide substrate (~shock and wear resistance)
Kalpakjian/Kennametal

23. Cutter Shape
and Geometry
Kalpakjian

24. Machining Costs
Kalpakjian

25. References