300 lm/W 16 lm/W 70 lm/W Illustration: © Johan Jarnestad ...
ME2258-LM
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Transcript of ME2258-LM
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EXERCISE NO. 1
SHEAR ANGLE MEASUREMENT
AIM :
To measure the shear angle to the given conditions.
TOOLS AND EQUIPMENTS REQUIRED :
Lathe, Single point turning tool, Micrometer.
PROCEDURE :
1. The workpiece is held in the chuck.
2. The known depth of cut is given (uncut chip thickness, t1).
3. The chip is taken for thickness inspection. Find the mean chip thickness, t2.
4. Calculate the chip thickness ratio, rc = t1 / t2
5. Calculate the shear angle for the given rake angle of the tool.
rc cos
tan = -----------
1 - rc sin where, - rake angle.
1. Repeat the same procedure to get few more readings and calculate the
mean shear angle.
2. Repeat the experiment for different depth of cuts.
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NOTE :
1. The value of Shear angle depends on the cutting conditions, tool geometry,
tool material and work material.
2. If the Shear angle is small, the plane of the shear is large, the chip is
thicker, more force is required to remove the chip.
3. If the shear angle is large, the plane of shear will be shorter and the chip is
thin. Hence, less force is required to remove the chip.
Workpiece
t1
t2
Tool
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CHIP THICKNESS :
LC = Least Count
SL. NO.
DEPTH PITCH SCALE HEAD SCALE HEAD SCALE CHIP
OF CUT READING COINCIDENCE READING THICKNESS
t1 (mm) (PSR) (HSC) HSR = HSC*LC t2 = PSR + HSR
1 0.25
2 0.25
3 0.25
4 0.25
1 0.50
2 0.50
3 0.50
4 0.50
SHEAR ANGLE :
SL. NO.
UNCUT CHIP CHIP SHEAR ANGLE
CHIP THICKNESS THICKNESS AVERAGE
THICKNESS RATIO SHEAR ANGLE
t1 (mm) t2 (mm) rc = t1 / t2
1 0.25
2 0.25
3 0.25
4 0.25
1 0.50
2 0.50
3 0.50
4 0.50
RESULT :
Thus the shear angle is found for different depth of cuts.
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EXERCISE NO. 2
MACHINING AN INTERNAL KEYWAY USING SLOTTING MACHINE
Aim :
To machine an internal keyway in the given workpiece to the dimensions as
shown in the figure using Slotting Machine.
Ø62Ø50
25
Tools Required :
Slotting Machine, Scriber, Divider, Steel Rule.
Procedure :
1. The given workpiece is measured for its initial dimensions.
2. With the help of scriber mark the keyway dimensions in the workpiece.
3. Fix the workpiece in the vice of the slotting machine.
4. After fixing the workpiece and the slotting tool, allow the ram to vertically
reciprocate.
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 workpiece is now checked for final dimensions.
Result :
Thus, internal keyway is machined in the given workpiece to the dimensions
as shown in the figure using Slotting Machine.
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EXERCISE NO. 3
SURFACE GRINDING
AIM :
To grind the workpiece to the given tolerance using surface grinding machine.
TOOLS AND EQUIPMENTS REQUIRED :
Surface Grinding machine, Micrometer.
PROCEDURE :
1. The given workpiece is checked for its initial dimensions.
2. The permanent magnet worktable is cleaned thoroughly.
3. Keep the workpiece over the worktable and push the lever to “ON” position
to hold the workpiece.
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 workpiece respectively.
6. Finally, the finished workpiece is checked for the given dimensions.
RESULT :
Thus the given workpiece is ground to the given tolerance using surface
grinding machine.
70
50
70
50
10 9±0.01
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EXERCISE NO. 4
ASSEMBLY OF BOLT & NUT (ASSEMBLY – I)
AIM :
To machine and assemble a Bolt & Nut to the given dimensions using
required machines.
301040
30
18
Chamfer 45° x 2
M 25.4 x 3.75
TOOLS AND EQUIPMENTS REQUIRED :
Lathe, Turning tool, Parting tool, Threading tool, Vernier caliper.
PROCEDURE :
1. The given workpiece is checked for its initial dimensions.
2. The workpiece is chucked and turned for the required dimensions.
3. The external thread is made on the workpiece.
4. The internal thread is made on another workpiece.
5. Check for the mating of internal and external threads formed.
RESULT :
Thus, a Bolt & Nut assembly is machined as per the given dimensions and
assembled using the required machines.
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EXERCISE NO. 5
ASSEMBLY OF DIE & PUNCH (ASSEMBLY – II)
AIM :
To machine and assemble a Die & Punch to the given dimensions using
required machines.
5
Ø55
1020
Ø50
5
Ø40
Ø40
Ø55
Ø50
10 20
TOOLS AND EQUIPMENTS REQUIRED :
Lathe, Vernier caliper.
PROCEDURE :
1. The given workpieces are checked for its initial dimensions.
2. The workpiece is chucked in lathe and machined to the projection
dimensions as given in the figure.
3. The other workpiece is machined for recess dimensions as given in the
figure.
4. Mate both the workpieces.
RESULT :
Thus, a Die & Punch assembly is machined as per the given dimensions and
assembled using the required machines.
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EXERCISE NO. 6
ASSEMBLY OF FLANGE COUPLING (ASSEMBLY – III)
AIM :
To machine and assemble the Flange Coupling as shown in the figure using
required machines.
TOOLS AND EQUIPMENTS REQUIRED :
Drilling machine, Drill set, Tap set, Bolts & Nuts, Vernier Caliper.
PROCEDURE :
1. The given workpieces are checked for its initial dimensions.
2. The center of the workpieces are marked and the Pitch Circ le Diameter is
marked in both the workpieces.
3. The first workpiece is drilled and tapped to the dimensions as shown in the
figure.
4. The second workpiece is drilled to the dimensions as shown in the figure.
5. Both the workpieces are mated together by using bolts and nuts.
6. Thus a Flange Coupling assembly is made using required machines.
8 mm tap, 4 holes
70 10 mm tap
50
PCD 35 mm
9 mm dia.,
4 holes
70 10 mm dia.
50
PCD 35 mm
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RESULT :
Thus, a Flange Coupling is machined as per the given dimensions and
assembled using the required machines.
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EXERCISE NO. 7
CAPSTAN LATHE
AIM :
To machine the workpiece to the given dimensions using capstan lathe.
TOOLS AND EQUIPMENTS REQUIRED :
Capstan Lathe, Stopper, drill chuck, counter sink bit, drill bit, turning tool,
parting off tool, Vernier Caliper.
PROCEDURE :
1. Prepare the tooling layout for the given workpiece.
2. Set the tools in their respective positions of the tool stations.
3. The workpiece is chucked and checked for the rotation.
4. The adjustment to the length of feed for each tool is adjusted by rotating
the adjustment screws.
5. Feed the tools in the required sequence to machine the given workpiece.
RESULT :
Thus the given workpiece is machined to the given dimensions using capstan
lathe.
18
20
12
18
12
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EXERCISE NO. 8
SPUR GEAR MILLING
AIM :
To machine a spur gear to the given module and number of teeth in the given
workpiece.
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.
Ø50
Ø18
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5. The cutter is mounted on the arbor. The cutter is centred 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 * 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.
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EXERCISE NO. 9
MACHINING OF HEXAGON IN SHAPING MACHINE
Aim :
To machine a hexagon in the given workpiece to the dimensions as shown in the figure using Shaping Machine.
Tools Required :
Shaping Machine, Scriber, Divider, Steel Rule, Chalk piece, Bevel Protractor.
Procedure :
1. The given workpiece is measured for its initial dimensions.
2. With the help of scriber, mark the hexagon dimensions in the workpiece.
3. Fix the workpiece in the vice of the shaping machine.
4. After fixing the workpiece and the shaping tool, allow the ram to
reciprocate.
5. Start the shaping process by giving the required depth by lowering the tool.
6. Slowly increase the depth of cut and repeat the procedure to make the
hexagon shape. 7. The workpiece is now checked for final dimensions.
Result :
Thus, a hexagon is machined in the given workpiece to the dimensi ons as
shown in the figure using Shaping Machine.
29 15