machining and machine tool (Types of milling machine)
- 2. Contents • Basic functions & purposes • Classifications • Kinematic system & working principle • Applications
- 3. Functions of Milling M/c • Producing flat surfaces at any orientation • Inclined surfaces • Special contours on m/c elements
- 4. Principles • Up milling: – More clamping forces – No effect with back clash in screw-nut systems • Down milling – Proper clamping is ensured – back clash affects the process & product
- 5. Major uses • Making flat surfaces (diff. orientations) • Slots and steps • Slitting • Rotary turning • Threads • Helical surfaces • Gushing in drills
- 6. Classifications • Purpose • Configuration • Spindle orientation • Automation • CNC
- 7. According to purpose – General purpose : • most versatile, non-automated • Low vol. of production – Single purpose : • specific operation , automated to some degree • Lot production – Special purpose : • Making special features using attachments • Batch production (automatic)
- 8. According to configuration • Knee type : – Non-automated – Piece production – Small size m/c
- 9. -contd. • Bed type : – Rigid & robust – Vertical spindle – Depth is given to cutter – Batch wise production
- 10. - contd. • Plano miller: – Many cutters simultaneously can work – (for large jobs having many plane surfaces) – Fast production
- 11. Contd. • Rotary table type: – Open / closed type – Work table rotates – High productivity – More than 1 spindle
- 12. According to spindle orientation- Contd. horizontal Vertical spindle Universal head
- 13. Base Ram Arbour Speed chain Feed chain Over running clutch
- 14. Milling cutters
- 15. classifications • Profile sharpened cutters – surface geometry doesn’t depend on tool shape – Slab or plain milling cutter – Side milling cutter – Slitting cutters – End milling cutter – Face milling cutter
- 16. Plain or slab milling cutter • Hollow straight HSS cylinders • 4 to 16 straight or helical flutes Feed
- 17. Side milling cutters • Large cutting teeth on periphery • Each tooth has peripheral cutting edge – Single sided milling cutter – Double sided milling cutter
- 18. Slitting cutters • Only one peripheral cutting edge • Cutter is larger in φ & thin • Large nos. but smaller in size • Only for slitting
- 19. End mills & shell mill
- 20. Face milling cutter • Larger φ:80 to 800 mm • Coated or uncoated carbide inserts • For larger jobs like lathe bed, planer beds
- 21. Contd. • Form relieved cutters – surface generated is the replica of the tool shape – Form cutters – Gear milling cutter – Spline shaft cutter – T-slot cutter – Thread milling cutter
- 22. characteristics • Flank surface is Archimedean spiral shape • Tooth are sharpened by grinding the rake face • To make 2D or 3D contours
- 23. Form cutters • Made of HSS or carbides
- 24. Gear teeth milling cutter Disc type cutter End mill type form cutter
- 25. Spline cutter • To make spline shaft • The cutter has the same shape to be produced • Indexing helps to generate the spline over the circumference
- 26. Thread milling • Short thread • Long thread