MADURAI INSTITUTE
OF ENGINEERING &
TECHNOLOGY
Pottapalayam Sivagangai District-630611.
DEPARTMENT OF MECHANICAL ENGINEERING
10122 ME407 MANUFACTURING
TECHNOLOGY LABORATORY - II
As per the Anna University Syllabus
from 2011-2012
Prepared by
Mr.R.BALAJI
Mr.S.PUNGAIYA
LIST OF EXPERIMENTS
S.NO
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EXPERIMENTS
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PAGE NO
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SIGNATURE
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I
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INTRODUCTION OF
SHAPING MACHINE
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INTRODUCTION OF
DRILLING MACHINE
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III
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INTRODUCTION OF
GRINDING MACHINE
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IV
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INTRODUCTION OF
SLOTTING MACHINE
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V
|
INTRODUCTION OF
MILLING MACHINE
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VI
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INTRODUCTION OF
LATHE MACHINE
|
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INTRODUCTION OF SHAPING MACHINE
The main functions of shaping machines
are to produce flat surfaces in different planes. The basic principle of
generation of flat surface by shaping machine. The cutting motion provided by
the linear forward motion of the reciprocating
tool and the intermittent feed motion provided by the slow transverse
motion of the job along with the bed result in producing a flat surface by
gradual removal of excess material layer by layer in the form of chips. The
vertical infeed is given either by descending the tool holder or raising the
bed or both. Straight grooves of various curved sections are also made in
shaping machines by using specific form tools. The single point straight or
form tool is clamped in the vertical slide which is mounted at the front face
of the reciprocating ram whereas the work piece is directly or indirectly
through a vice is mounted on the bed.
• Shaping
machines
It
is already mentioned that shaping
machines are neither productive nor versatile. However, its limited
applications include :
Δ Machining
flat surfaces in different planes. Fig. 4.4.7 shows how flat surfaces are
produced in shaping machines by single point cutting
tools in (a)
horizontal, (b) vertical and (c) inclined planes.
Δ Making features like slots, steps etc. which
are also bounded by flat
surfaces. Fig. 4.4.8 visualises the
methods of machining (a) slot, (b) pocket (c) T-slot
and (d) Vee-block in shaping machine by single
point tools.
Δ Forming grooves bounded by short width curved
surfaces by using
single point but form tools. Fig. 4.4.9
typically shows how (a) oil grooves and
(b) straight tooth of spur gears can be
made in shaping machine.
Δ Some other machining applications of shaping
machines are cutting
external keyway and splines, smooth
slitting or parting, cutting teethof rack for
repair etc. using simple or form type
single point cutting tools.
Some unusual work can
also be done, if needed, by developing and
using special attachments.
EX: NO: Date:
MACHINING OF SQUARE IN SHAPING MACHINE
Aim
To machine a square in the given work
piece to the dimensions as shown in the figure using shapping machine.
Tools and equipments required
Shaping machine
Scriber
Divider
Steel rule
Chalk piece
Bevel protractor
Procedure
1) The
given work piece is measured for its initial dimension.
2) With
the help of scriber, mark the hexagon dimensions in the work piece.
3) Fix
the work piece and the shaping tool allow the ram to reciprocate.
4) Start
the shaping process by giving the required depth by lowering the tool.
5) Slowly
increase the depth of cut and repeat the procedure to make the square shape.
6) The
work piece is now checked for final dimensions.
Result
Thus a square was machined in the
given work piece to the dimensions as shown in the figure using shaping machine.
INTRODUCTION
OF DRILLING MACHINE
Drilling machines are generally
or mainly used to originate through or blind straight cylindrical holes in
solid rigid bodies and/or enlarge (coaxially) existing (premachined) holes.
• of different diameter ranging
from about 1 mm to 40 mm
• of varying length depending
upon the requirement and the diameter of the drill
• in different materials
excepting very hard or very soft materials like rubber, polythene etc.
Application
of drilling machines
Drilling machines of different
capacity and configuration are basically used for originating cylindrical holes
and occasionally for enlarging the existing holes to full or partial depth. But
different types of drills are suitably used for various applications depending
upon work material, tool material, depth and diameter of the holes.
Radial drilling machine
This usually large drilling
machine possesses a radial arm which along with the drilling head can swing and
move vertically up and down as can be seen in Fig. 4.2.4. The radial, vertical
and swing movement of the drilling head enables locating the drill spindle at
any point within a very large space required by large and odd shaped jobs.
There are some more versatile radial drilling machines where the drill spindle
can be additionally swivelled and / or tilted.
EX: NO: Date:
DRILLING
HOLES ON PCD ON THE WORK PIECE
Aim
Aim of this practice is to
machine holes on pitch circle drawn on a given work piece.
Tools and equipments required
Radial Drilling machine
Drill bit
Dot punch
Tap
Chalk piece and Hammer
Compass.
Procedure
1) Draw A pitch circle on the
given work piece using a compass.
2) Separate its circumference
by the number of holes to be cut.
3) Each interval has to be
drilled on this pitch circle.
4) A punch is made to identify
the place to be drilled.
5) Work piece is fixed on the
radial drilling machine and holes are made.
Result
Thus drilling operation is performed on the PCD
Drawn on the work piece.
INTRODUCTION
OF GRINDING MACHINE
Grinding Machines are also
regarded as machine tools. A distinguishing feature of grinding machines is the
rotating abrasive tool. Grinding machine is employed to obtain high accuracy
along with very high class of surface finish on the workpiece. However, advent
of new generation of grinding wheels and grinding machines, characterised by
their rigidity, power and speed enables one to go for high efficiency deep
grinding (often called as abrasive milling) of not only hardened material but
also ductile materials.
Conventional grinding machines can be broadly classified as:
(a) Surface grinding machine
(b) Cylindrical grinding machine
(c) Internal grinding machine
(d)
Tool and cutter grinding machine
Surface grinding machine:
This machine may be similar to a
milling machine used mainly to grind flat surface. However, some types of
surface grinders are also capable of producing contour surface with formed
grinding wheel.
Basically there are four
different types of surface grinding machines characterised by the movement of
their tables and the orientation of grinding wheel spindles as follows:
• Horizontal spindle and
reciprocating table
• Vertical spindle and
reciprocating table
• Horizontal spindle and rotary
table
• Vertical spindle and rotary
table
Horizontal spindle reciprocating table grinder
This machine with various motions required for
grinding action. A disc type grinding wheel performs the grinding action with
its peripheral surface. Both traverse and plunge grinding can be carried out in
this machine.
A: rotation
of grinding wheel B: reciprocation of worktable C: transverse feed D: down feed
EX: NO: Date:
SURFACE GRINDING OPERATION
Aim
To grind the work piece to the given tolerance using surface
grinding machine.
Tools And Equipments Required
Surface Grinding machine
Micrometer
Procedure
1)
The given
work piece is checked for its initial dimensions.
2)
The
permanent magnet worktable is cleaned thoroughly.
3)
Keep the work
piece over the worktable and push the lever to “ON” position to hold the work
piece.
4)
The
required depth of cut is given by raising the table.
5)
The
reciprocating and cross feed is given to grind the required length and width of
the work piece respectively.
6)
Finally,
the finished work piece is checked for the given dimensions.
Result
Thus the
given work piece is ground to the given tolerance using surface grinding
machine.
INTRODUCTION OF SLOTTING MACHINE
Slotting machines can simply be
considered as vertical shaping machine where the single point (straight or
formed) reciprocates vertically (but without quick return effect) and the workpiece,
being mounted on the table, is given slow longitudinal and / or rotary feed as
can be seen. In this machine also the length and position of stroke can be
adjusted. Only light cuts are taken due to lack of rigidity of the tool holding
ram for cantilever mode of action. Unlike shaping and planing machines,
slotting machines are generally used to machine internal surfaces (flat, formed
grooves and cylindrical). Shaping machines and
slotting machines, for their low productivity, are generally used, instead of
general production, for piece production required for repair and maintenance.
Like shaping and slotting machines, planing machines, as such are also becoming
obsolete and getting replaced by plano-millers where instead of single point
tools a large number of large size and high speed milling cutters are used.
The schematic view of slotting
machine is typically.The vertical slide holding the cutting tool is
reciprocated by a crank and connecting rod mechanism, so here quick return
effect is absent. The job, to be machined, is mounted directly or in a vice on
the work table. Like shaping machine, in slotting machine also the fast cutting
motion is imparted to the tool and the feed motions to the job. In slotting
machine, in addition to the longitudinal and cross feeds, a rotary feed motion
is also provided in the work table.
The intermittent rotation of the
feed rod is derived from the driving shaft with the help of a four bar linkage
as shown in the kinematic diagram.It is also indicated how the intermittent
rotation of the feed rod is transmitted to the leadsrews for the two linear
feeds and to the worm – worm wheel for rotating the work table. The working
speed, i.e., number of strokes per minute, Ns may be changed, if necessary by
changing the belt-pulley ratio or using an additional “speed gear box”,
whereas, the feed values are changed mainly by changing the amount of angular
rotation of the feed rod per stroke of the tool. This is done by adjusting the
amount of angle of oscillation of the paul The directions of the feeds are
reversed simply by rotating the tapered paul by 180o as done in shaping
machines.
•
Slotting machine
Slotting machines are very similar to shaping
machines in respect of
Machining
principle, tool-work motions and general applications. However, relative to
shaping machine, slotting machines are characterized by :
Δ Vertical tool reciprocation with down stroke
acting
Δ Longer stroke length
Δ Less strong and rigid
Δ An additional rotary feed motion of the work table
Δ Used mostly for machining internal surfaces.
The
usual and possible machining applications of slotting machines are :
ο Internal
flat surfaces
ο Enlargement
and / or finishing non-circular holes bounded by a
number of flat surfaces.
ο Blind
geometrical holes like hexagonal socket.
ο Internal
grooves and slots of rectangular and curved sections.
ο Internal
keyways and splines, straight tooth of internal spur gears,
internal curved surface of circular section, internal oil grooves etc.
which are not possible in shaping machines.
However, it has to be borne in mind that
productivity and process capability of slotting machines are very poor and
hence used mostly for piece production required by maintenance and repair in
small industries. Scope of use of slotting machine for production has been
further reduced by more and regular use of broaching machine
EX: NO: Date:
MACHINING OF INTERNAL KEYWAY USING SLOTTING
MACHINE
Aim
To
machine an internal keyway in the givens work piece to the dimensions as shown
in fig using slotting machine.
Tools and equipments required
Slotting machine
Scriber
Divider
Steel
rule
Procedure:
1) The given work piece
is measured for its initial dimensions
2) With the help of
scriber mark the keyway dimensions in the work piece.
3) Fix the work piece in
the vice of the slotting machine.
4) After fixing the work
piece and the slotting tool allow the ram to vertically reciprocal.
5) Start the slotting
process by giving the required depth by horizontally moving the vice
6) Slowly increase the
depth of cut and repeat the procedure to make the required shape.
7) The work piece is
checked for final dimensions.
Result:
Thus
the internal keyway is machined in the given work piece to the dimensions.
INTRODUCTION OF MILLING MACHINE
The basic function of milling machines is to produce
flat surfaces in any orientation as well as surfaces of revolution, helical
surfaces and contoured surfaces of various configurations. Such functions are
accomplished by slowly feeding the workpiece into the equispaced multiedge
circular cutting tool rotating at moderately high speed as indicated in Fig.
4.3.1. Upmilling needs stronger holding of the job and downmilling needs
backlash free screw-nut systems for feeding.
Milling machines of various type
are widely used for the following purposes using proper cutting tools called
milling cutters :
• Flat surface in vertical,
horizontal and inclined planes
• Making slots or ribs of various
sections
• Slitting or parting
• Often producing surfaces of
revolution
• Making helical grooves like
flutes of the drills
• Long thread milling on large
lead screws, power screws, worms etc and short thread milling for small size
fastening screws, bolts etc.
• 2-D contouring like cam
profiles, clutches etc and 3-D contouring like die or mould cavities
• Cutting teeth in piece or batch
production of spur gears, straight toothed bevel gears, worm wheels, sprockets,
clutches etc.
• Producing some salient features
like grooves, flutes, gushing and profiles in various cutting tools, e.g.,
drills, taps, reamers, hobs, gear shaping cutters etc.
Classification of milling machines
Milling machines can be broadly
classified;
(a) According to nature of purposes
of use :
• general purpose – most
versatile commonly used mainly for piece or small lot production
• single purpose – e.g.,
thread milling machines, cam milling machines and slitting machine which are
generally used for batch or lot production.
• Special purpose – these
are used for lot or mass production, e.g., duplicating mills, die sinkers,
short thread milling etc.
(b) According to configuration and motion of the work-holding
table / bed
• Knee type : typically
shown in Fig. 4.3.2. In such small and medium duty machines the table with the
job/work travels over the bed (guides) in horizontal (X) and transverse (Y)
directions and the bed with the table and job on it moves vertically (Z) up and
down.
• Bed type : Usually of
larger size and capacity; the vertical feed is given to the milling head
instead of the knee type bed
Machine
parts :
1. column
2. bed
3. cross slide
4. work table
5. ram
6. ram support
7. arbour support
Table feed
motions :
a. longitudinal feed
b. cross feed
c. vertical feed
• Planer type:
These heavy duty
large machines, called plano-miller, look like planing machine where the single point tools
are replaced by one or a number of milling heads; generally used for machining
a number of longitudinal flat surfaces simultaneously, viz., lathe beds, table
and bed of planning machine etc.
• Rotary table type :
Such open or
closed ended high production milling machines possess one large rotary
work-table and one or two vertical spindles as typically shown in Fig. 4.3.5;
the positions of the job(s) and the milling head are adjusted according to the
size and shape of the job.
(c) According to the orientation of the
spindle(s).
• Plain horizontal knee type (Fig. 4.3.6)
This
non-automatic general purpose milling machine of small to medium size possesses
a single horizontal axis milling arbour; the work-table can be linearly fed
along three axes (X,Y, Z) only; these milling machines are most widely used for
piece or batch production of jobs of relatively simpler configuration and
geometry
• Horizontal axis (spindle) and swivelling bed
type
These are very
similar to the plain horizontal arbour knee type machines but possess one
additional swivelling motion of the work-table
• Vertical spindle type
In this machine,
typically shown in Fig. 4.3.7, the only spindle is vertical and works using end
mill type and face milling cutters; the table may or may not have swivelling
features
• Universal head milling machine
These versatile
milling machines, typically shown in Fig. 4.3.8, not only possess both
horizontal milling arbour and the vertical axis spindle, the latter spindle can
be further tilted about one (X) or both the horizontal axes (X and Y) enabling
machining jobs of complex shape.
(d)
According to mechanisation / automation and production rate
Milling machines
are mostly general purpose and used for piece or small lot production. But like
other machine tools, some milling machines are also incorporated with certain
type and degree of automation or mechanisation to enhance production rate and
consistency of product quality. In this respect milling machines can be further
classified as follows :
• Hand mill
(milling machine) - this is the simplest form of milling machine where even
the table feed is also given manually as can be seen in Fig. 4.3.9.
Fig. 4.3.9 Hand mill
milling machine
• Planer and
rotary table type vertical axis milling machines are not that automated but
provide relatively higher production rate
• Tracer
controlled copy milling machine, typically shown in Fig. 4.3.10, are
mechanically or hydraulically operated semi-automatic milling machines used for
lot production of cams, dies etc by copying the master piece
• Milling
machines for short thread milling may be considered single purpose and
automatic machine being used for mass production of small bolts and screws.
EX: NO: Date:
SPUR GEAR MILLING
Aim
To machine gear to the
given module and number of teeth in the given work piece.
Tools and equipments required
Milling
machine
Vernier
caliper
Mandrel.
Procedure:
1. Calculate
the gear tooth proportions.
Blank
diameter = (Z + 2) m
Tooth
depth = 2.25 m
Tooth width = 1.5708 m
Where,
Z =
Number of teeth required
m
= module
2. Indexing
calculation
Index
crank movement = 40 / Z
3. The
dividing head and the tail stock are bolted on the machine table. Their axis
must be set parallel to the machine table.
4. The
gear blank is held between the dividing head and tailstock using a mandrel. The
mandrel is connected with the spindle of dividing head by a carrier and catch
plate.
5. The
cutter is mounted on the arbor. The cutter is centered accurately with the gear
blank.
6. Set
the speed and feed for machining.
7. For
giving depth of cut, the table is raised till the periphery of the gear blank
just touches the cutter.
8. The
micrometer dial of vertical feed screw is set to zero in this position.
9. Then
the table is raised further to give the required depth of cut.
10. The
machine is started and feed is given to the table to cut the first groove of
the blank.
11. After
the cut, the table is brought back to the starting position.
12. Then
the gear blank is indexed for the next tooth space.
13. This
is continued till all the gear teeth are cut.
Calculation
Z = No. of
teeth = 23
m =
module = 2 mm
Blank
Diameter = (Z + 2) m
= (23 + 2) 2
= 50 mm
Tooth Depth =
2.25 m
=
2.25 x 2
=
4.5 mm
Indexing
Calculation = 40 / Z
=
40 / 23
=
1 17/23
Result:
Thus the required gear is machined using the
milling machine to the required number of teeth.
EX: NO: Date:
MACHINE A KEYWAY USING END MILLING CUTTER IN
VERTICAL MILLING MACHINE
Aim:
To machine a cubic mild steel bar and
make a keyway slot on the surface.
Tool required:
Vertical
milling machine,
Vernier
caliper,
Machine
Vice
Procedure:
1) The cubic cast iron or
ms bar is placed in material shaping machine.
2) The blank is placed in
the machine vice after shaping the work.
3) The knee of the
vertical milling machine is move towards the cutter.
4) The machine vice is
move by vertical slotter and then axis is setup on the work piece.
5) The depth of the
vertical milling cutter is given by means of spindle adjustment.
6) The running action of
cutter by using pulley the vertical milling cutter cuts the cubic bar.
7) By moving the work by horizontal
block table.
8) The keyways on the
machine vice work that by move the work table.
9) The work is continuous
on the work by moving the slotter from one region to another gender region.
Result:
Thus
the given work piece is and milled to the given dimension using vertical
milling.
INTRODUCTION OF LATHE
MACHINE
Turning
is a machining process to produce parts round in shape by a single point tool
on lathes. The tool is fed either linearly in the
direction parallel or perpendicular to the axis of rotation of the workpiece,
or along a specified path to produce complex rotational shapes. The primary
motion of cutting in turning is the rotation of the workpiece, and
the secondary motion of cutting is the feed motion.
Cutting conditions in turning
Cutting
speed in turning V in m/s is related to the rotational speed of the
workpiece by the equation:V = πDN where D is the diameter of the workpiece, m;
N is the rotational speed of the workpiece, rev/s.
For machining in machine tools
the job and the cutting tool need to be moved relative to each other.
The tool-work
motions are :
• Formative
motions : - cutting motion
-
feed motion
• Auxiliary
motions : - indexing motion
-
relieving motion etc
In lathes
o Cutting motion
is attained by rotating the job
o Feed motion by
linear travel of the tool
- either axially for longitudinal feed
- or radially for cross feed
It is noted, in general,
• The job gets
rotation (and power) from the motor through the belt-pulley, clutch and then
the speed gear box which splits the input speed into a number (here 12) of
speeds by operating the cluster gears.
• The cutting
tool derives its automatic feed motion(s) from the rotation of the spindle via
the gear quadrant, feed gear box and then the appron mechanism where the
rotation of the feed rod is transmitted
- either to the pinion which being rolled along the
rack provides the longitudinal feed
- or to the screw of the cross slide for cross or
transverse feed.
• While cutting
screw threads the half nuts are engaged with the rotating leadscrew to
positively cause travel of the carriage and hence the tool parallel to the
lathe bed i.e., job axis.
• The feed-rate
for both turning and threading is varied as needed by operating the Norton gear
and the Meander drive systems existing in the feed gear box (FGR). The range of
feeds can be augmented by changing the gear ratio in the gear quadrant connecting
the FGB with the spindle
• As and when
required, the tailstock is shifted along the lathe bed by operating the
clamping bolt and the tailstock quil is moved forward or backward or is kept
locked in the desired location.
• The
versatility or working range of the centre lathes is augmented by using several
attachments like
- Taper turning attachment
- Thread milling attachment
- Copying attachment
EX: NO: Date:
CAPSTAN AND TURRET LATHE
Aim:
To machine the work piece to the given
dimension using capstan lathe.
Tools
required:
Capstan
lathe
Counter sink bit
Drill bit
Stopper
Drill chuck
Procedure:
1) Prepare tooling layout
for the given work piece.
2) Set the tools in the respect
position of the tool rotation.
3) The adjustment to the
lathe of
head for each tool is adjusted by rotating the adjusted
4) Feed the tools in the
required sequences to machine given work piece for the given dimension using
capstan lathe.
Result:
Thus
the tools in the required sequences to machine given work pieces for the given
dimension using capstan lathe.
EX: NO: Date:
MACHINING THE COMPONENTS FOR INTERFACING FIT
ASSEMBLY
Aim:
To
machine the components for interference fit assembly using a lathe and a
drilling machine.
Materials
required:
Mild steel polished rod 32 x 16mm
Tools
required:
Turning tool
Parting off tool
Drill bit
Vernier caliper
Outside caliper
Inside caliper
Procedure:
1) The given work piece
is held originally in the chuck.
2) The single point
cutting tool is set on the tool post.
3) The machine is
switched on.
4) The straight turning
and facing operations are done on the one half the work piece as per the given
dimensions.
5) Then the drill bit of
required drill size is held in tail stock and drilling is done for the required
depth in the work piece.
6) The two parts are
assembled for getting a clearance fit assembly.
Result:
The given work piece as shown in
figure is subjected to machining operations to become a finished work piece.
EX: NO: Date:
MACHINING
THE COMPONENTS FOR CLEARANCE FIT ASSEMBLY
Aim:
To machine the components for
clearance fit assembly using lathe.
Materials required:
Mild steel
Polished round rod 32 x 110mm
Tools required:
Turning tool
Parting
off tool
Drill
bit
Outside caliper
Vernier
caliper
Inside
caliper
Procedure:
1) The given work piece
is hold rigitly in the chuck.
2) The single point cutting
tool is set on the tool post.
3) The machine is
switched on
4) The straight turning
and facing operations are done on the one half if the workpiece as per the
given dimension.
5) The machine is
switched off.
6) The parting tool is
fixed and by parting off operation the work piece is cut into two parts as per
the dimensions
7) Two parts are
assembled per getting a clearance fit assembly.
Result:
The
given workpiece is subjected in machine operations to become a finished
workpiece.
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