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FAKULTI KEJURUTERAAN MEKANIKAL UNIVERSITI TEKNIKAL MALAYSIA MELAKA. FORMAT REPORT. REPORT 1. Title and Front Cover 2. Objective 3. Brief of project (1 page) 4. Working method and procedure existing project. For CNC include programming. - PowerPoint PPT PresentationTRANSCRIPT
1
FORMAT REPORT
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
REPORT 1. Title and Front Cover2. Objective3. Brief of project (1 page)4. Working method and procedure existing project. For CNC include
programming.5. Working method and procedure for proposed project (new project
proposed by student. (For CNC include programming)6. Discussion
-Problem encountered-Countermeasure-Suggestion
7. Safety precaution 8. Conclusion9. Appendix (if any) Report not more 30 pages comb binding; 1.5 line spacing; font size
12. Submit date: Last working day of Report Week. Penalty will be
imposed for late submission.
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FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
FUNDAMENTAL OF MACHINING
Fundamental Of Machining
3
Fundamental Of Machining
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Chapter Outline
1. Mechanics of Cutting
2. Cutting Forces and Power
3. Temperatures in Cutting
4. Tool Life: Wear and Failure
5. Surface Finish and Integrity Machinability
4
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Cutting processes remove material from the surface of a workpiece by producing chips. Some of the more common cutting processes are as follow:
1. Turning, in which the workpiece is rotated and a cutting tool removes a layer of material as it moves to the left.
2. Cutting-off operation, where the cutting tool moves radially inward and separates the right piece from the bulk of the blank.
5
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Cutting processes remove material from the surface of a workpiece by producing chips. Some of the more common cutting processes are as follow:
3. Slab-milling operation, in which a rotating cutting tool removes a layer of material from the surface of the workpiece.
4. End-milling operation, in which a rotating cutter travels along a certain depth in the workpiece and produces a cavity.
6
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Fig BELOW shows some examples of common machining operations.
7
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Fig BELOW shows the schematic illustration of the turning operation showing various features.
8
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Next Fig shows the schematic illustration of a two-dimensional cutting process, also called orthogonal cutting:
(a) Orthogonal cutting with a well-defined shear plane, also known as the Merchant model. Note that the tool shape, depth of cut, and the cutting speed, V, are all independent variables
(b) Orthogonal cutting without a well-defined shear plane.
9
INTRODUCTION
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
10
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
The factors that influence the cutting process are outlined in Next Table.
In order to appreciate the contents of this table, let’s now identify the major independent variables in the cutting process as follows: (a) tool material and coatings; (b) tool shape, surface finish, and sharpness; (c) workpiece material and condition; (d) cutting speed, feed, and depth of cut; (e) cutting fluids; (f) characteristics of the machine tool; and (g) workholding and fixturing.
11
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
12
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Dependent variables in cutting are those that are influenced by changes in the independent variables listed above, and include:
(a) type of chip produced, (b) force and energy dissipated during
cutting, (c) temperature rise in the workpiece, the
tool, and the chip, (d) tool wear and failure, and (e) surface finish and surface integrity of the
workpiece.
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Fig below (a) shows the schematic illustration of the basic mechanism of chip formation by shearing. (b) Velocity diagram showing angular relationships among the three speeds in the cutting zone.
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sin1
costan
r
r
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Cutting Ratio It can be seen that the chip thickness, tc, can be
determined by knowing the depth of cut, to and α and Φ.
The ratio of to / tc is known as the cutting ratio (or chip-thickness ratio), r, and is related to the two angles by the following relationships:
cos
sin
c
o
t
tr
15
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Cutting Ratio The reciprocal of r is known as the chip-
compression ratio or factor and is thus a measure of how thick the chip has become compared to the depth of cut; hence, the chip-compression ratio always is greater than unity.
The depth of cut also is referred to as the undeformed chip thickness.
16
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Cutting Ratio The reciprocal of r is known as the chip-
compression ratio or factor and is thus a measure of how thick the chip has become compared to the depth of cut; hence, the chip-compression ratio always is greater than unity.
The depth of cut also is referred to as the undeformed chip thickness.
17
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Shear Strain The shear strain, , that the material undergoes can
be expressed as
Note that large shear strains are associated with low shear angles or with low or negative rake angles.
tancotOC
OB
OC
AO
OC
AB
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Shear Strain The shear angle has great significance in the
mechanics of cutting operations. It influences force and power requirements, chip
thickness, and temperature. This analysis yielded the expression
where β is the friction angle and μ is related to the coefficient of friction, at the tool–chip interface by the expression μ = tan β .
2245
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Shear Strain Among the many shear–angle relationships developed,
another useful formula that generally is applicable is
The coefficient of friction in metal cutting generally ranges from about 0.5 to 2, indicating that the chip encounters considerable frictional resistance while moving up the tool’s rake face.
45
20
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Velocities in the cutting zone Since mass continuity has to be maintained,
A velocity diagram also can be constructed, where from trigonometric relationships, we obtain the equation
cos
sin
or
VV
VVtVVt
c
rccco
sincoscoscs VVV
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Velocities in the cutting zone
where Vs is the velocity at which shearing take place in the shear plane.
Note also that
These velocity relationships will be utilized further when describing power requirements in cutting operations.
V
V
t
tr c
c
o
22
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cutting The four main types are:
1. Continuous
2. Built-up edge
3. Serrated or segmented
4. Discontinuous
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingContinuous chips Continuous chips usually are formed with ductile
materials, machined at high cutting speeds and/or high rake angles.
The deformation of the material takes place along a narrow shear zone called the primary shear zone.
Continuous chips may develop a secondary shear zone because of high friction at the tool–chip interface; this zone becomes thicker as friction increases.
24
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttinga) Continuous chip in
cutting brassb) Secondary shear
zone in cutting copper
c) Built Up edge in cutting sintered tungsten
d) Serrated chip in cutting S.steel
e) Discontinuous chip in cutting brass
25
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingContinuous chips Deformation in continuous chips also may
take place along a wide primary shear zone with curved boundaries.
This problem can be alleviated with chip breakers (to follow) or by changing parameters, such as cutting speed, feed, depth of cut, and by using cutting fluids.
26
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingBuilt-up edge chips A built-up edge (BUE) consists of layers of
material from the workpiece that gradually are deposited on the tool tip—hence the term built-up.
Built-up edge commonly is observed in practice. It is a major factor that adversely affects surface
finish, however, a thin, stable BUE usually is regarded as desirable because it reduces tool wear by protecting its rake face.
27
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingBuilt-up edge chips The tendency for BUE formation can be reduced
by one or more of the following means:
1. Increase the cutting speeds
2. Decrease the depth of cut
3. Increase the rake angle
4. Use a sharp tool
5. Use an effective cutting fluid
6. Use a cutting tool that has lower chemical affinity for the workpiece material
28
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingSerrated chips Serrated chips are semicontinuous chips with
large zones of low shear strain and small zones of high shear strain, hence the latter zone is called shear localization.
Metals with low thermal conductivity and strength that decreases sharply with temperature (thermal softening) exhibit this behavior, most notably titanium.
29
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingDiscontinuous chips Discontinuous chips consist of segments that may be
attached firmly or loosely to each other. Discontinuous chips usually form under the following
conditions:
1. Brittle workpiece materials, because they do not have the capacity to undergo the high shear strains involved in cutting.
2. Workpiece materials that contain hard inclusions and impurities or have structures such as the graphite flakes in gray cast iron.
3. Very low or very high cutting speeds
30
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingDiscontinuous chips
4. Large depths of cut.
5. Low rake angles.
6. Lack of an effective cutting fluid.
7. Low stiffness of the toolholder or the machine tool, thus allowing vibration and chatter to occur.
31
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingDiscontinuous chips Because of the discontinuous nature of chip
formation, forces continually vary during cutting.
Consequently, the stiffness or rigidity of the cutting-tool holder, the workholding devices, and the machine tool are important in cutting with serrated chips as well as with discontinuous chips.
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingChip Curl In all cutting operations performed on metals,
as well as nonmetallic materials such as plastics and wood, chips develop a curvature (chip curl) as they leave the workpiece surface.
Among factors affecting the chip curl are:1. The distribution of stresses in the primary and
secondary shear zones.
2. Thermal effects.
3. Work-hardening characteristics of the workpiece material.
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingChip Curl4. The geometry of the cutting tool.
5. Cutting fluids. Generally, as the depth of cut decreases, the radius
of curvature decreases; that is, the chip becomes curlier.
Also, cutting fluids can make chips become more curly (the radius of curvature decreases), thus reducing the tool–chip contact area and concentrating the heat closer to the tip of the tool. As a result, tool wear increases.
34
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingChip Breakers Continuous and long chips are undesirable as
they tend to become entangled and severely interfere with machining operations and also become a potential safety hazard.
Next Fig(a) shows the schematic illustration of the action of a chip breaker. Note that the chip breaker decreases the radius of curvature of the chip and eventually breaks it. (b) Chip breaker clamped on the rake face of a cutting tool. (c) Grooves in cutting tools acting as chip breakers. Most cutting tools used now are inserts with built-in chip-breaker features.
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cutting
36
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingChip Breakers Chip breakers have traditionally been a piece of
metal clamped to the tool’s rake face, which bend and break the chip.
However, most modern cutting tools and inserts now have built-in chip-breaker features of various designs.
Next Fig shows the chips produced in turning: (a) tightly curled chip; (b) chip hits workpiece and breaks; (c) continuous chip moving radially away from workpiece; and (d) chip hits tool shank and breaks off.
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cutting
38
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cutting
Chip Breakers In interrupted-cutting operations (such as
milling), chip breakers generally are not necessary, since the chips already have finite lengths.
39
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingControlled contact on tools Cutting tools can be designed so that the tool–chip
contact length is reduced by recessing the rake face of the tool some distance away from its tip.
This reduction in contact length affects chip-formation mechanics.
Primarily, it reduces the cutting forces and, thus, the energy and temperature.
Determination of an optimum length is important as too small a contact length would concentrate the heat at the tool tip, thus increasing wear.
40
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Types of chips produced in metal cuttingCutting nonmetallic materials A variety of chips are encountered in cutting
thermoplastics, depending on the type of polymer and process parameters, such as depth of cut, tool geometry, and cutting speed.
Many of the discussions concerning metals also are applicable generally to polymers.
Because they are brittle, thermosetting plastics and ceramics generally produce discontinuous chips.
41
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique Cutting The majority of machining operations involve tool
shapes that are three-dimensional, thus the cutting is oblique.
Whereas in orthogonal cutting, the chip slides directly up the face of the tool, in oblique cutting, the chip is helical and at an angle i, called the inclination angle.
Next Fig(a) shows the schematic illustration of cutting with an oblique tool. Note the direction of chip movement. (b) Top view, showing the inclination angle, i. (c) Types of chips produced with tools at increasing inclination angles.
42
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique Cutting
43
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique Cutting Note that the chip in previous Fig flows up the rake
face of the tool at angle (chip flow angle), which is measured in the plane of the tool face.
Angle αi is the normal rake angle, and it is a basic geometric property of the tool.
This is the angle between line oz normal to the workpiece surface and line oa on the tool face.
The effective rake angle, αe is
ie ii sincossinsin 221
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MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique Cutting Next Fig shows the schematic illustration of a
right-hand cutting tool. The various angles on these tools and their effects on machining.
Although these tools traditionally have been produced from solid tool-steel bars, they have been replaced largely with Next Fig inserts made of carbides and other materials of various shapes and sizes.
45
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique Cutting
46
MECHANICS OF CUTTING
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Oblique CuttingShaving and skiving Thin layers of material can be removed from
straight or curved surfaces by a process similar to the use of a plane to shave wood.
Shaving is useful particularly in improving the surface finish and dimensional accuracy of sheared parts and punched slugs.
47
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Knowledge of the cutting forces and power involved in machining operations is important for the following reasons:• Data on cutting forces is essential so that:a. Machine tools can be properly designed to minimize distortion of the machine components, maintain the desired dimensional accuracy of the machined part, and help select appropriate toolholders and workholding devices.b. The workpiece is capable of withstanding these forces without excessive distortion.• Power requirements must be known in order to enable the selection of a machine tool with adequate electric power.
48
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Fig Below (a) shows the Forces acting in the cutting zone during two-dimensional cutting. Note that the resultant force, R, must be colinear to balance the forces. (b) Force circle to determine various forces acting in the cutting zone.
49
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
The thrust force, acts in a direction normal to the cutting speed.
These two forces produce the resultant force, R, as can be seen from the force circle.
Note that the resultant force can be resolved into two components on the tool face: a friction force, F, along the tool-chip interface and a normal force, N, perpendicular to it. It can also be shown that
cos
sin
RN
RF
50
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Note also that the resultant force is balanced by an equal and opposite force along the shear plane and is resolved into a shear force, and a normal force.
It can be shown that these forces can be expressed as follows:
cossin
sincos
tcn
tcs
FFF
FFF
51
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Because the area of the shear plane can be calculated by knowing the shear angle and the depth of cut, the shear and normal stresses in the shear plane can be determined.
The ratio of F to N is the coefficient of friction, μ, at the tool–chip interface, and the angle β is the friction angle.
The magnitude of μ can be determined as
tan
tan
tc
ct
FF
FF
N
F
52
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Thrust force A knowledge of the thrust force in cutting is important
because the tool holder, the workholding devices, and the machine tool must be sufficiently stiff to support this force with minimal deflections.
We also can show the effect of rake angle and friction angle on the direction of thrust force by noting from previous Fig. that
tan
sin
ct
t
FF
RF
53
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Thrust force A knowledge of the thrust force in cutting is important
because the tool holder, the workholding devices, and the machine tool must be sufficiently stiff to support this force with minimal deflections.
We also can show the effect of rake angle and friction angle on the direction of thrust force by noting from previous Fig. that
tan
sin
ct
t
FF
RF
54
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Power Power is the product of force and velocity. Thus, the
power input in cutting is
This power is dissipated mainly in the shear zone (due to the energy required to shear the material) and on the rake face of the tool (due to tool–chip interface friction).
The power dissipated in the shear plane is
VFcPower
ssVFshearingforPower
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Vwt
VFu
o
sss
cFVfrictionforPower
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Power Letting w be the width of cut, the specific energy for
shearing, us, is given by
Similarly, the power dissipated in friction is
and the specific energy for friction, uf is
oo
cf wt
Fr
Vwt
FVu
56
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Power The total specific energy, ut thus is
Because of the many factors involved, reliable prediction of cutting forces and power still is based largely on experimental data, such as those given in Next Table.
The sharpness of the tool tip also influences forces and power. Because it rubs against the machined surface and makes the deformation zone ahead of the tool larger, duller tools require higher forces and power.
fst uuu
57
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
58
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Measuring cutting forces and power Cutting forces can be measured using a force
transducer (typically with quartz piezoelectric sensors), a dynamometer or a load cell (with resistance-wire strain gages placed on octagonal rings) mounted on the cutting-tool holder.
It is possible to calculate cutting force from the power consumption during cutting, provided that the mechanical efficiency of the machine tool is known or can be determined.
59
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Example :Relative energies in cutting
In an orthogonal cutting operation, to = 0.13 mm, V = 120 m/min, α = 10º and the width of cut=6 mm. It is observed that tc = 0.23 mm, Fc = 500 N and Ft = 200 N. Calculate the percentage of the total energy that goes into overcoming friction at the tool-chip interface.
60
CUTTING FORCES & POWER
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
Solution The percentage of the energy can be expressed as
%32or32.0
500
565.0286Percentage
N28632sin539
32
10539cos500
N539500200
cos
sin
565.0
22
23.013.0
energyTotalenergyFriction
F
FFR
RF
RF
r
ct
c
tt
FFr
VFFV
c
o
cc
c
61
THE END
FAKULTI KEJURUTERAAN MEKANIKALUNIVERSITI TEKNIKAL MALAYSIA MELAKA
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