23-200-0105A
Basic Mechanical Engineering
Dr. Harikrishnan S
Assistant Professor
Division of Mechanical Engineering
Syllabus
Syllabus…
Machine Tools
Machine Tool Operations
• A machine, which performs the material removal operations with tools, to produce
desired shape and size of the work- piece is known as machine tool
Types of Machine Tools
1. Lathe
2. Shaping machine
3. Drilling machine
4. Milling machine
5. Grinding machine
6. Slotting machine
7. Planer machine
Tools used
• Single Point Cutting Tool: One cutting
edge(used in lathe)
• Multipoint Cutting Tool: Number of teeth or
cutting edges on the periphery
LATHE
• It is a general purpose machine tool , which removes excess material from
the work piece, in the form of chips, by rotating the work piece against a
single point cutting tool
Working Principle
• Hold the work piece and to rotate it about an axis
• Cutting toll is fed either parallel or perpendicular to the axis of the work piece
removes material from the rotating work to give the required size and shape
• Tool is moved parallel to the axis of rotation of the work piece gives a cylindrical
surface
• Tool is moved perpendicular to the axis of rotation of the work piece gives a flat
surface
Components of Lathe
1. Bed
2. Headstock
3. Tailstock
4. Carriage
5. Lathe centre
6. Feed mechanism
1. Bed
• Base foundation of the lathe
• Headstock, tailstock, carriage…etc are
mounted on the bed
• Provides strength & rigidity to the machine
• Top of the bed is provided with guides or
ways for carriage & tailstock
• Material- Cast Iron
2. Headstock
• Permanently mounted on the bed at the left
end
• Spindle is supported in headstock, spindle is
a hollow cylindrical shaft supported by
bearings
• Work holding devices such as face plate,
driving plate or chucks may be mounted on
the spindle nose
• Headstock has a gear box for changing the
speed of rotation
• of spindle and thereby the speed of rotation of
work piece
• Spindle is driven by a motor
3.Tailstock
• It is mounted on the bed at the right
end and can be clamped at any
convenient position
• It supports one end of the work piece
• It is also used for holding a tool for
performing operations such as drilling,
reaming…etc
4. Carriage
• Carriage consists of several parts that
serves to support the cutting tool and to
control the action of the cutting tool
• It can be moved along the bed ways
provided at the top of the bed
5. Lathe Centre
• Lathe centres are
tapered components fit into
spindles provided in the headstock
and tailstock
• Centre connected to the
headstock is called live
centre(rotates with the spindle)
• Centre connected to the
tailstock is called dead
centre(does not rotate, only support
the work piece)
6. Feed mechanism
• Movement of tool relative to the work
piece is termed as feed
a. Longitudinal feed: tool is moved
parallel to the axis of rotation of
work piece
b. Cross feed: tool is moved
perpendicular to the axis of
rotation of work piece
c. Angular feed: tool is moved at an
angle to the axis of rotation of
work piece
Lathe Operations
Turning Operation
Taper Turning Operation
Facing Operation
Chamfering Operation
Thread Cutting
Spinning Operation
Grooving Operation
Drilling Operation
Boring Operation
Knurling Operation
Tools used
• Single Point Cutting Tool: One cutting
edge(used in lathe)
• Multipoint Cutting Tool: Number of teeth or
cutting edges on the periphery
HMT
Drilling
Operation
Drilling Operation
• Operation of making holes in a workpiece
by forcing a rotating tool called a drill
against it.
• Drill:- Multipoint cutting tool
• Drill is a cylindrical bar with helical
grooves cut or formed in the body of the
drill
• To provide cutting edges and permit
removal of chips
• To allow the cutting fluid to reach the
cutting edges.
Drilling Machine
Drill chuck and key
Operations using Drilling Machine
Drilling Operation
• Operation of producing a circular hole using a drill
by removing metal from the workpiece
• Drill bit is a multi-point cutting tool
• It cuts by applying pressure and rotation of the
drill, forms chips at the cutting edge
Boring Operation
• Enlarging an already existing hole by means of an
adjustable single-point tool
• Single point tool traversed through the hole and
parallel to the axis of the rotation removes metal
and thus increases the diameter of the hole
Boring tool
Reaming Operation
• Operation of finishing and sizing an
already existing hole
• The tool used is called the
reamer which has multiple cutting
edges
• This operation removes a
very small amount of metal from
the drilled hole
Reamer
Milling
Operation
Milling Operation
• Process of removal of metal by feeding the work piece against rotating
multi-point cutter
• As the cutter rotates, each cutting edge removes small amount of
material from the work piece
Milling Cutters
Milling Machine
Types of Milling
1. Plane Milling
2. Slot Milling
3. Gear Milling
Plane Milling
• Production of flat surfaces with the milling cutter axis parallel to the
surface being milled
Plane Milling Cutter
Slot Milling
• T-slot cutter is used
• First of all a plain slot is cut on the work piece using an
end milling cutter. Then the T-slot cutter is fed from one
end of the workpiece
• Neck portion of the cutter passes through the already
milled plain slot
Gear Milling
• Process by which gears are produced using gear cutters
• Profile of the cutter corresponds to the tooth space of the gear
Gear Cutter
Gear Cutters
Thank You
