Lathes are machines that remove metal from a workpiece to shape it. There are many types of lathes including engine, turret, and CNC lathes. A lathe consists of a bed, headstock, carriage, apron, tailstock, and other components. It performs operations like turning, facing, boring, drilling, tapering, and thread cutting. The document provides details on the components, types, operations, and accessories of lathe machines.

1. PRESENTATION ON LATHE MACHINE

2. PRINCIPLE OF LATHE
 Lathe is a machine, which is used to remove
metal from the workpiece to required shape
and size.

3. COMPONENTS OF LATHE

4. TYPES OF LATHES
•Speed Lathe :
It is the simplest type lathe. It is mainly used for metal
spinning, polishing etc.
•Bench Lathe :
It is small sized engine lathe mounted on bench. It is used
for turning small and light weight workpiece.
•Tool Room Lathe :
It is used for production of small tools, gauges, fixtures and
accurate parts in tool room.

5. •Turret Lathe :
These lathes are used in mass production and for
heavy duty workpieces.
•Capsten Lathe :
These lathes are used in mass production used for
light duty workpieces.
•Special Purpose Lathe :
These lathes are modification of engine lathes
developed for machining special types of workpices.

6. •Automatic Lathe
•Engine Lathe
•Tracer Lathe
•Computer Controlled lathe
•Swiss Type Automatic Lathe
•Duplicating Lathe

7. COMPUTER NUMERICALLY CONTROLLED LATHE
 Computer Numerical Controls (CNC)
 Equipped with one or more turrets
 Each turret is equipped with a variety of tools
 Performs several operations on different surfaces of the workpiece

8. TURRET LATHE
Capable of performing multiple
cutting operations on the
same workpiece
 Turning
 Boring
 Drilling
 Thread cutting
 Facing
Turret lathes are very versatile
Types of turret lathes
 Ram-type: ram slides in a
separate base on the
saddle
 Saddle type:
 more heavily
constructed
 Used to machine large
workpeiceces

9. ENGINE LATHE

10. BENCH LATHE AUTOMATIC LATHE

11. PARTS OF LATHE
•Bed : Supports all major components
•Carriage: Slides along the ways and consists of the cross-slide,
tool post, apron
•Headstock : Holds the jaws for the work piece, supplies power to
the jaws and has various drive speeds
•Tailstock : Supports the other end of the workpiece
•Feed Rod and Lead Screw : Feed rod is powered by a set of
gears from the headstock

12. LATHE BED
•Heavy, rugged
casting
•Made to support
working parts of
lathe
•On top section
are machined
ways
•Guide and align
major parts of
lathe

13. HEADSTOCK
 Clamped on left-hand end
of bed
 Headstock spindle
 Hollow cylindrical shaft
supported by bearings
 Provides drive through
gears to work-holding
devices

14. CARRIAGE
 Used to move cutting
tool along lathe bed
 Consists of three
main parts
 Saddle
 Cross-slide
 Apron

15. APRON

16. 16
TAILSTOCK

17. ACCESSORIES
 Chucks :
 Three jaw chuck
 Four jaw chuck
 Collet chuck
 Centres:
 Live centre
 Dead centre
 Tipped centre
 Ball centre
 Mandrels :
 Plain mandrel
 Stepped mandrel
 Collared mandrel
 Screwed mandrel

18.  Chucks :
• Three Jaw Chuck (Self Centering Chuck) :
This chuck is used to hold circular
workpiece and is available in sizes from
100mm to 600 mm.
 Four Jaw Chuck (Independent Chuck) :
It is used to hold rectangular,
sqare and irregular shaped workpieces .
ACCESSORIES

19.  Collet Chuck :
 Pull poerating rod
 Push poerating rod
It is ideal for holding tube and thin
walled workpieces.

20.  Centres:
 Live Centre
 Dead Centre
 Ball Centre
 Pipe Centre
 Half Centre
 Tipped Centre

21.  Mandrels :
 Plain Mandrel
 Collared Mandrel
 Screwed Mnadrel
 Stepped Mandrel

22. LATHE OPERATIONS

23. •Turing
•Facing
•Boring
•Drilling
•Taper
•Camfering
•Grooving
•Forming
•Reaming
•Undercutting
•Thread cutting
•Knurling
LATHE OPERATIONS

24. BORING
 Boring produces circular internal profiles in hollow workpieces
 Boring mills are used for large workpieces
 Holes can be bored up to 20M if needed
 See fig. 22.20
 Machines are available with a variety of features
 Horizontal boring machines
 Jig borers

25. TURNING
 Forces in turning
 Cutting force: acts downward on the tool tip
 Thrust force: acts in the longitudinal direction
 Radial force: acts in the radial direction
 Roughing and Finishing Cuts
 Rough cut: high speed cut with little regard for dimensional
tolerance
 Finishing cut: lower feed rate and depth of cut
 Tool Materials, Feeds, and Cutting Speeds
 Cutting Fluids

26. CONCEPT OF SPEED, FEED AND DEPTH OF CUT
•Cutting speed=Πdn mm/min
1000
•Feed :
•It is expressed in mm/rev
•Depth of cut :
t=D-d mm
2

27. SINGLE POINT CUTTING TOOL GEOMETRY
•Clearance
•Rake
•End cutting
edge angle
•Side cutting
edge angle