An Experiment Study Of The Effect Of Cutting Speed, Depth Or Cut And Feed Rate To Roundness In CNC Lathe.
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
AN EXPERIMENT STUDY OF THE EFFECT OF CUTTING
SPEED, DEPTH OF CUT AND FEED RATE TO ROUNDNESS IN
CNC LATHE
This report submitted in accordance with requirement of the Universiti Teknikal
Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering
(Manufacturing Process) with Honours.
by
MOHD HAFIZ BIN ISMAIL
FACULTY OF MANUFACTURING ENGINEERING
2009
TEKNIKATMATAYSIAMETAKA
UNIVERSITI
TAJUK:Studyon Effectof CuttingSpeed,Depthof Cut and FeedRateto
Roundness
2OO8|2O09
Semester2
SESI
PENGAJIAN:
Saya MOHDHAFIZBINISMAIL
Laporan
PSMini disimpan
di Perpustakaan
Universiti
membenarkan
mengaku
kegunaan
sepertiberikut:
TeknikatMataysia
Metaka(UTeM)dengansyarat-syarat
TeknikalMalaysia
Metakadanpenutis.
1. TesisadalahhakmitikUniversiti
Melakadibenarkan
membuatsatinan
UniversitiTeknikalMataysia
z. Perpustakaan
penutis.
pengajian
izin
sahajadengan
untuktujuan
bahanpertukaran
membuatsalinantesisini sebagai
3. Perpustakaan
dibenarkan
pengajian
tinggi.
antarainstitusi
4. *Sitatandakan(r/)
z
n
!
(Mengandungi
maklumatyangberdarjahkesetamatan
yangtermaktubdi dalam
Malaysia
ataukepentingan
RASM|
19721
AKTARAHSTA
yangtelahditentukan
maktumat
TERHAD
TERHAD (Mengandungi
otehorganisasi/badan
di manapenyetidikan
dijatankan)
SULIT
TIDAKTERHAD
6nP*$H$ffii1"'**
UnivcaitlTclnikrlMalrPh lldaka
fQrungEertunci1200,AYerKcnh
75450ideleka
BandarTenqqara,
81000Kutai.Johor.
!-
i
I
rarikh: ti /r /oal
Tarikh:
. Jika tesisini SULITatauTERHAD,
sitalampirkansuratdaripadapihakberkuasa/organisasi
sebagaiSULITatauTERHAD.
sekatisebabdan tempohtesisini pertudikelaskan
denganmenyatakan
TEKNIKALMALAYSIAMELAKA
UNIVERSITI
AyerKeroh,75450Melaka
KarungBerkunci'1200,
Tel : 06-2332421.Faks: 06 2332414
Email: fkp@kutkm.edu.mv
PEMBUATAN
FAKULTIKEJURUTERAAN
Rujukan Kami (Our Ref) :
Rujukan Tuan (Your Ref):
14 Mei 2009
Pustakawan
UTeM
Perpustakawan
Metaka
UniversitiTeknikatMataysia
HangTuahJaya,
75450,Melaka
Saudara,
SULIT/TERHAD
LAPORANPROJEK
LAPORANPSMSEBAGAI
PENGKELASAN
(MANUFACTURING
PEMBUATAN
PROCESS):
KEJURUTERMN
SARJANA
MUDA
MOHDHAFIZBINISMAIL
bahawalaporanPSMyangtersebutdi atas bertajuk
Sukacitadimaklumkan
DEPTH
OF
OFTHEEFFECT
OF CUTTING
SPEED,
EXPERIMENT
STUDY
'AN
lN CNCLATHE'mohondikelaskan
CUTAND FEEDRATETO ROUNDNESS
untuktempohLIMAtahundaritarikhsuratini.
sebagai
SULIT/TERHAD
Terimakasih.
Sekiandimaktumkan.
Yangbenar,
SUIAIMAN
En.Moh
Pensyarah
,
Pembuatan
.
FakuttiKejuruteraan
xotto.
Aritrn suuurr
lcnryanh
F.kultiXquruEnrnlcrnluahn
Univcr3iti
Tatnitrl M.t ysh lHrkr
Xarung
lcrkunci12f0,Apr Xcmh
t5450tiGtkr
DECLARATION
I hereby, declaredthis report entitled "AN EXPERIMENT STUDY OF THE
EFFECT OF CUTTING SPEED, DEPTH OF CUT AND FEED RATE TO
ROUNDNESSIN CNC LATHE" is the resultof my own researchexceptas cited
in references.
Signature
Author's Name
MOHD HAF
Date
14MAY 2009
TN ISMAIL
APPROVAL
This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a
partial fulfillment of the requirements for the degree of Bachelor of Manufacturing
Engineering (Manufacturing Process)with Honours. The member of the supervisory
committee is as follow:
(Signatureof Supervisor)
EN MOHD AMRI BIN SULAIMAN
(Official Stamp of Supervisor)
ro|0' Attl lltl slttAlf,rtl
lcnelrrlt
F.k$ Kdru$n$ lrn$urhn
Univsnitifaksikalt||l.t!i' f&{'' '
lfiuttg fcilufi$ 1200'Atu fcill
75f50lftl*.
ABSTRACT
This project entitled “An Experiment Study of The Effect of Cutting Speed, Depth of cut
and Feed rate to roundness in CNC lathe” is contain about the effect of parameter on
roundness and to get the best parameter setting for the CNC lathe machine in term of
roundness. This project objective to investigate the contribution of the feed rate, cutting
speed and depth of cut in CNC lathe machine at FKP machine shop laboratory by
conducting several machining process and then analyzed the roundness of the finish
product using CNC Roundness tester machine.
The overall effectiveness of this project needs methodology to collect the data,
calculating the data and analyze the data. The collecting data is at all samples after the
machining operation. After get the result, the data will test using CNC Roundness tester
machine using least Square Circle Method. Then, the result will analyze using Design of
Experiment (DOE) to get the contribution of parameter in roundness.
Finally, this study will also produce the best parameter setting and also verify the most
effect parameter on roundness that need to be controlled. With this study and
implementation on the machine it can the quality of the roundness.
i
DEDICATION
For my beloved mother and father
ii
ACKNOWLEDGEMENT
First and foremost, I would like to express my highest appreciation to my
supportive supervisor, Mr Amri bin Sulaiman for his supervision and support in
completing this thesis.
Next I would like to dedicate my thankfulness and acknowledge to laboratory
technicians, who has been so warmth and kind to provide sincere assistance and good
cooperation during the training period. Their cooperation is much appreciated. . In
addition, I would like to convey thanks to Miss Liew Pay Jun for her assistance, which
really spends her time to teach me a lot of knowledge regarding to the DOE.
Last but not least, I would like to convey my appreciation to all the staff of
Faculty of Manufacturing Engineering, FKP, my friend and colleagues for their support
and their help in the project. Thank you.
iii
TABLE OF CONTENT
Abstract
i
Dedication
ii
Acknowledgement
iii
Table of content
iv
List of table
vii
List of figure
viii
CHAPTER 1 1
INTRODUCTION
1
1.1 OBJECTIVE
2
1.2 SCOPE
2
1.3 PROBLEM STATEMENT
3
CHAPTER 2
4
LITERATURE REVIEW
4
2.1 CNC lathe machine
5
2.1.1 CNC Lathe Machine Model Haas SL-20
5
2.1.2 Machine specification
7
2.1.3 Fundamental of CNC lathe cutting (Graham T.smith, 2002)
8
2.2 Roundness
8
2.2.1 Roundness measurement
9
2.2.1.1 Method in Measure Roundness
2.2.1.2
Least Square Method
9
11
2.3 Cutting Parameter
12
2.3.1 Feed Rate
12
2.3.2 Cutting speed
14
iv
2.3.2.1
Effect of Work Speed on Geometrical Characteristic
2.3.3 Depth of Cut
16
2.4 Material
16
2.4.1 Aluminum
2.4.1.1
14
16
Aluminum characteristic
17
2.4.2 Aluminum 6061
18
2.4.2.1
Chemical Composition for Aluminum 6061
18
2.4.2.2
Mechanical Properties
19
2.5 Design of Experiment (DOE)
19
2.5.1 DOE overview
19
2.5.2 Factorial design
20
2.5.3 Implementation of factorial design
21
2.6 Mahr Formtester MMQ44 (Mahr GmbH, 2007)
22
CHAPTER 3
24
METHODOLOGY
24
3.1 Flow Chart
25
3.2 Material
27
3.2.1 Material Selection
27
3.3 Machining Setup Parameters
27
3.3.1 Parameter Setup by Applying Two Level Factorial Method
27
3.3.2 Data Table
28
3.3.3 Methodology for DOE
29
3.4 CNC Lathe Machine Set-up
30
3.4.1 Specimens Preparation
30
3.4.2 Parameter Setting
31
3.4.3 Machining Procedure
31
3.4.4 Methodology of Machining Operation Using the CNC lathe machine
32
3.5 Analysis
32
3.5.1 Methodology of Roundness Measurement
32
3.5.2 Procedure to measure the roundness using CNC Roundness
33
v
3.6 Data Analysis
34
3.6.1 Design of Experiment (DOE)
35
3.7 Gantt Chart Of The Study For PSM 1
36
3.8 Gantt Chart Of The Study For PSM 2
37
CHAPTER 4
38
RESULT AND ANALYSIS
39
4.1 Result of roundness of Aluminum 6061
40
CHAPTER 5
45
DISCUSSION
45
5.1 Roundness Numerical result analysis
47
5.2 Roundness graphical result analysis
48
5.3 Finding from the result
50
CHAPTER 6
51
CONCLUSION
51
6.1 Conclusion
51
6.2 Recommendation
52
REFERENCES
53
APPENDICES
55
vi
LIST OF TABLE
2.1
The machine specification of CNC lathe machine Model SL-20
7
2.2
Cutting speed for various material
15
2.3
Mechanical properties for aluminum 6061
18
2.4
Example of 2k factorial design
22
3.1
The arrangement of the high and low using full Factorial design
28
3.2
The arrangement of the high and low value using full Factorial design
28
3.3
DOE matrix
35
3.4
Gantt chart of the study for Projek Sarjana Muda 1 (PSM 1)
36
3.5
Gantt chart of Projek Sarjana Muda 2 (PSM 2)
37
4.1
Roundness result for sample A
39
4.2
Roundness result for sample B
39
4.3
Optimum parameter effect
40
vii
LIST OF FIGURE
2.1
CNC lathe machine SL-20 Series
6
2.2
View for CNC lathe machine SL-20 series
6
2.3
The diagram shows the trace and Y, the distance from the spindle
center to the trace at the angle
9
2.4
Problem with plug gauge method
10
2.5
The least square circles diagram on roundness material
12
2.6
The cutting forces reduce with the increasing of cutting speed
16
2.7
Schematic diagram of the main feature of just one configuration
for roundness testing machine
23
3.1
The flow chart of the project
26
3.2
Provided Aluminum 6061 Dimension
27
3.3
Plan for DOE
30
3.4
The flow chart of machining methodology
32
3.5
The CNC Roundness – Formtester MMQ44 manufactured by Mahr at
the Metrology Laboratory
3.6
33
Work piece been placed on chuck and probe been place near the
work piece surface
34
4.1
Pareto chart of the effect for sample A
40
4.2
The Pareto Chart of the Effects for sample B
40
4.3
The Normal Probability Plot of the Effects for sample B
41
4.4
The Normal Probability Plot of the Effects for sample B
41
4.5
The Main Effects Plot (data means) for sample A
42
4.6
The Main Effects Plot (data means) for sample B
42
4.7
The Interaction Plot (data means) for sample A
43
4.8
The Interaction Plot (data means) for sample B
43
4.9
The cube plot (data means) for sample A
45
viii
4.10
The cube plot (data means) for sample B
45
5.1
Roundness average against number of experiment
47
5.2
Sample main effect plot for sample B
49
5.3
Sample interaction plot for sample B
49
ix
CHAPTER 1
INTRODUCTION
The purpose of this report is to study on three main controllable parameter that has to be
consider in CNC lathe in term of roundness. The three main parameters are speed, depth
of cut and feed rate. This study also determines which parameter has the big influence in
roundness. In order to get the result several work piece will go through machining
operation. The material that use is Aluminum 6161. During the operation the parameter
will be change in every sample. The parameter are been setup by applying the Design of
Experiment (DOE). After machining, the sample will be test using MAHr CNC
Roundness Tester Machine. After that, all the roundness result will be compare again
three parameters. From the result it will produce the standard parameter and from that
also can know the parameter that effects the most in roundness.
1
1.1
I.
OBJECTIVE
To investigate the contribution of feed rate, cutting speed and depth of cut in
CNC lathe machine.
II.
To analyzed the roundness of the finish product using CNC Roundness tester
machine
III.
To find the best parameter for aluminum 6061 and determine the relationship
between the parameter and the roundness using Design of Experiment (DOE)
IV.
To identify the parameter that effect the most in roundness
1.2
SCOPE
Scope of this project is conducting a machining operating using the CNC lathe machine
to study the parameter in term of roundness. The machine that be used is CNC Lathe
Machine Model Haas SL-20 manufactured by HAAS Automation Inc. The parameters
that involve in this analysis are depth of cut; cutting speed and feed rate are set followed
to the Design of Experiment (DOE).The material that used is solid cylinder aluminum
6061 with 30mm diameter. The other parameters are constant such as coolant and many
more. The roundness test will be using the Mahr Formtester MMQ44 at the metrology
lab and method that be used of each sample is least Square Circle Method. The result
analysis will be done base on Factorial Design analysis using Minitab software.
2
1.3
PROBLEM STATEMENT
Roundness is one of geometrical tolerance that needs to be maintain when machining
cylindrical part. To obtain good tolerance of roundness three controllable parameter
need to be controlled. The parameters are depth of cut, speed (rpm) and feed rate that is
setup by the operator in the program. However, the value of parameters depends on the
size of the work piece to be machined. These controllable parameters are usually
adjusted to get the fine quality of roundness.
Before this there are no appropriate parameters when cutting the aluminum 6061 in term
of roundness. Hence, this study will develop the appropriate parameter for the CNC
lathe machine model SL-20 for this material.
This experiment also tries to get which parameter that affects the most in cutting
aluminum 6061. There is previous research that related to this study and therefore on
this experiment try to verify those research.
3
CHAPTER 2
LITERATURE REVIEW
A literature review was conducted to gain knowledge about the roundness and parameter
that effect in roundness using CNC lathe. There were a lot of articles about the cutting
parameter and roundness but only the little is related with these researches. In additional
to the literature search done at the library, discussion with those familiar with this
project and gathered more articles from internet. Even the gathered research article is not
directly to this project, it still helping reader for understanding these researches and also
for their study. The literature review will include in the machine, roundness, material,
parameter, Design of Experiment and roundness tester.
4
2.1
CNC lathe machine
2.1.1 CNC Lathe Machine Model Haas SL-20
For this PSM project will use CNC lathe model SL-20 series from Haas Automation that
available in FKP laboratory. CNC lathes are designed to meet the needs of modern
machine shops, now and long into the future. The SL Series offers a wide range of
capacities, and our space-saving Big Bore option increases capacity further while
retaining the original footprint. The SL-20, with a max turning capacity of 10.3" x 20"
and an 8.3" chuck, has a bar capacity of up to 2.0".
SL- 20 high-performance turning centers also feature massive headstock castings with
symmetric ribs for rigidity and thermal stability; on-the-fly wyes-delta switching for
peak performance throughout the rpm range; and embedded chip trays and high-volume
coolant systems for efficient chip removal. For control features advanced tool
management, single-button features, 15-inch color LCD monitor and a USB port. With
this feature it raised CNC turning to new levels of reliability, ease and productivity.
To simplify the ordering process, first determine the size of lathe needed to meet job
requirements, and then select the options, such as a hydraulic tailstock, versatile live
tooling, the automated Servo Bar 300 bar feeder, or the Big Bore option for larger bar
capacity in the original footprint. Options may be ordered in pre-packaged groups, or
selected individually for a custom configuration (Haas Automation Inc. 2008).
5
Figure 2.1 : CNC lathe machine SL-20 Series(Haas Automation Inc. 2008).
Figure 2.2: View for CNC lathe machine SL-20 series (Haas Automation Inc. 2008).
6
2.1.2 Machine specification
Table 2.1: The machine specification of CNC lathe machine Model SL-20 (Haas Automation Inc. 2008).
MAIN SPINDLE
AVAILABILITY
TURNING
DIAMETERS
TURNING LENGTHS
MAXIMUM SWING
CHUCK DIAMETER
BAR CAPACITY
NOSE: A2-5
Standard
NOMINAL:--
MAXIMUM:--
NOMINAL:10.000
"
MAXIMUM:10.000 "
5.300 "
STANDARD:-MAXIMUM:-0.875
DRIVE MOTOR (HP): 8.0
HEADSTOCK - SPINDLE 1
NOSE: A2-6
BORE: 3.000 "
SPEED: 50 - 4000 RPM
DRIVE MOTOR (HP): 20.0
OPTIONS (top speed):
OPTIONS:
3400 RPM
30.0
5000 RPM
7000 RPM
RANGE: 1
INDEX INCREMENT (degrees): 0.001
DIRECTION
TURNING
DIAMETERS
TURNING LENGTHS
Horizontal
NOMINAL:8.000 "
MAXIMUM:8.200 "
NOMINAL:15.000
"
MAXIMUM:16.300 "
OPTION: 17.500
23.000 "
MAXIMUM SWING
CHUCK DIAMETER
BAR CAPACITY
STANDARD:8.300
"
STANDARD:2.000
"
MAXIMUM:10.000 "
MAXIMUM:2.500 "
MAX. NUMBER OF SIMULTANEOUS CUTTING TOOLS: 1
MACHINE NET WEIGHT(pounds):9000
7
2.1.3 Fundamental of CNC lathe cutting (Graham T.smith, 2002)
There are two main factors influence a cutting process, which are independent variables
and dependent variables. The dependent variables that are influences by changes in the
independent variables such as:
Force and energy dissipated in the cutting process.
Temperature rise in the workpiece, the chip, and the tool.
Wear and failure of the tool.
Surface finish produced on the workpiece after machining.
The major independent variables in the cutting process are follows:
2.2
Tool material, coating, and tool condition.
Tool shape, surface finish, sharpness.
Work pieces material, condition, and temperature.
Cutting parameter such as speed, feed rate, and depth of cut.
Cutting fluid.
The characteristic of machine tool, such as its stiffness and damping.
Work holding and fixtures.
Roundness
In all manufacturing process roundness is one of the important things. In order to get the
best roundness it affected by lot of factors like cutting tool, depth of cut, cutting speed,
feed rate, type of material, coolant and many more. Roundness or out of roundness can
be as the radial deviation of the actual profile from the ideal roundness. When the
parameters are not selected properly it will effect the roundness of the product. If the
8
speed increase and feed decreases, loss of precision in roundness tends to increase
(Engineering statistic handbook, 2007)
2.2.1 Roundness measurement
The measurement of roundness can be made by two ways. The first way is to use
Coordinate measuring machine (CMM) and the second one is using MAHr Roundness
Tester Machine. Using roundness tester machine the machine will compare the
roundness from the product with actual sample roundness result. Three measurement of
roundness were taken at different location.
2.2.1.1 Method in Measure Roundness
Measurements of roundness require 360° traces of the workpiece made with a turntabletype instrument or a stylus-type instrument. A least squares fit of points on the trace to a
circle define the parameters of noncircularity of the workpiece. A diagram of the
measurement method is shown below (Engineering statistic handbook, 2007).
Figure 2.3: The diagram shows the trace and Y, the distance from the spindle center to the trace at the
angle (Engineering statistic handbook, 2007)
9
They are four reference circles are internationally accepted for roundness measurements.
They are:
i. Maximum radius inscribing circle (MIC);[6] The MIC is the largest circle just
contained by the profile of a work piece. It is also known as the plug gauge circle and is
intended for shafts (Guru S.M and Tsai D.M, 1998).
A circle is drawn within all the data and is expanded until it is constrained by
three valleys (David Whitehouse, 2002).
The center obtains by this method need not to be unique (David Whitehouse,
2002).
For this method there is ambiguity if there are two equally good centers like
in the dumbbell shape (David Whitehouse, 2002).
Two maximum
circumscribing circles
of same amplitude but
different centers
Figure 2.4: Problem with plug gauge method (Engineering statistic handbook, 2007)
ii. Minimum radius circumscribing circle (MCC) (Guru S.M and Tsai D.M, 1998).
The MCC is the smallest circle that just contains the profile of a work piece.
It is also known as the ring gauge circle and is intended for holes (Guru S.M
and Tsai D.M, 1998).
A circle is drawn around all the data and then shrunk onto to the data to get
the minimum size circle (David Whitehouse, 2002).
This has to have just three point of contact between the data and the circle
(David Whitehouse, 2002).
10
AN EXPERIMENT STUDY OF THE EFFECT OF CUTTING
SPEED, DEPTH OF CUT AND FEED RATE TO ROUNDNESS IN
CNC LATHE
This report submitted in accordance with requirement of the Universiti Teknikal
Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering
(Manufacturing Process) with Honours.
by
MOHD HAFIZ BIN ISMAIL
FACULTY OF MANUFACTURING ENGINEERING
2009
TEKNIKATMATAYSIAMETAKA
UNIVERSITI
TAJUK:Studyon Effectof CuttingSpeed,Depthof Cut and FeedRateto
Roundness
2OO8|2O09
Semester2
SESI
PENGAJIAN:
Saya MOHDHAFIZBINISMAIL
Laporan
PSMini disimpan
di Perpustakaan
Universiti
membenarkan
mengaku
kegunaan
sepertiberikut:
TeknikatMataysia
Metaka(UTeM)dengansyarat-syarat
TeknikalMalaysia
Metakadanpenutis.
1. TesisadalahhakmitikUniversiti
Melakadibenarkan
membuatsatinan
UniversitiTeknikalMataysia
z. Perpustakaan
penutis.
pengajian
izin
sahajadengan
untuktujuan
bahanpertukaran
membuatsalinantesisini sebagai
3. Perpustakaan
dibenarkan
pengajian
tinggi.
antarainstitusi
4. *Sitatandakan(r/)
z
n
!
(Mengandungi
maklumatyangberdarjahkesetamatan
yangtermaktubdi dalam
Malaysia
ataukepentingan
RASM|
19721
AKTARAHSTA
yangtelahditentukan
maktumat
TERHAD
TERHAD (Mengandungi
otehorganisasi/badan
di manapenyetidikan
dijatankan)
SULIT
TIDAKTERHAD
6nP*$H$ffii1"'**
UnivcaitlTclnikrlMalrPh lldaka
fQrungEertunci1200,AYerKcnh
75450ideleka
BandarTenqqara,
81000Kutai.Johor.
!-
i
I
rarikh: ti /r /oal
Tarikh:
. Jika tesisini SULITatauTERHAD,
sitalampirkansuratdaripadapihakberkuasa/organisasi
sebagaiSULITatauTERHAD.
sekatisebabdan tempohtesisini pertudikelaskan
denganmenyatakan
TEKNIKALMALAYSIAMELAKA
UNIVERSITI
AyerKeroh,75450Melaka
KarungBerkunci'1200,
Tel : 06-2332421.Faks: 06 2332414
Email: fkp@kutkm.edu.mv
PEMBUATAN
FAKULTIKEJURUTERAAN
Rujukan Kami (Our Ref) :
Rujukan Tuan (Your Ref):
14 Mei 2009
Pustakawan
UTeM
Perpustakawan
Metaka
UniversitiTeknikatMataysia
HangTuahJaya,
75450,Melaka
Saudara,
SULIT/TERHAD
LAPORANPROJEK
LAPORANPSMSEBAGAI
PENGKELASAN
(MANUFACTURING
PEMBUATAN
PROCESS):
KEJURUTERMN
SARJANA
MUDA
MOHDHAFIZBINISMAIL
bahawalaporanPSMyangtersebutdi atas bertajuk
Sukacitadimaklumkan
DEPTH
OF
OFTHEEFFECT
OF CUTTING
SPEED,
EXPERIMENT
STUDY
'AN
lN CNCLATHE'mohondikelaskan
CUTAND FEEDRATETO ROUNDNESS
untuktempohLIMAtahundaritarikhsuratini.
sebagai
SULIT/TERHAD
Terimakasih.
Sekiandimaktumkan.
Yangbenar,
SUIAIMAN
En.Moh
Pensyarah
,
Pembuatan
.
FakuttiKejuruteraan
xotto.
Aritrn suuurr
lcnryanh
F.kultiXquruEnrnlcrnluahn
Univcr3iti
Tatnitrl M.t ysh lHrkr
Xarung
lcrkunci12f0,Apr Xcmh
t5450tiGtkr
DECLARATION
I hereby, declaredthis report entitled "AN EXPERIMENT STUDY OF THE
EFFECT OF CUTTING SPEED, DEPTH OF CUT AND FEED RATE TO
ROUNDNESSIN CNC LATHE" is the resultof my own researchexceptas cited
in references.
Signature
Author's Name
MOHD HAF
Date
14MAY 2009
TN ISMAIL
APPROVAL
This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a
partial fulfillment of the requirements for the degree of Bachelor of Manufacturing
Engineering (Manufacturing Process)with Honours. The member of the supervisory
committee is as follow:
(Signatureof Supervisor)
EN MOHD AMRI BIN SULAIMAN
(Official Stamp of Supervisor)
ro|0' Attl lltl slttAlf,rtl
lcnelrrlt
F.k$ Kdru$n$ lrn$urhn
Univsnitifaksikalt||l.t!i' f&{'' '
lfiuttg fcilufi$ 1200'Atu fcill
75f50lftl*.
ABSTRACT
This project entitled “An Experiment Study of The Effect of Cutting Speed, Depth of cut
and Feed rate to roundness in CNC lathe” is contain about the effect of parameter on
roundness and to get the best parameter setting for the CNC lathe machine in term of
roundness. This project objective to investigate the contribution of the feed rate, cutting
speed and depth of cut in CNC lathe machine at FKP machine shop laboratory by
conducting several machining process and then analyzed the roundness of the finish
product using CNC Roundness tester machine.
The overall effectiveness of this project needs methodology to collect the data,
calculating the data and analyze the data. The collecting data is at all samples after the
machining operation. After get the result, the data will test using CNC Roundness tester
machine using least Square Circle Method. Then, the result will analyze using Design of
Experiment (DOE) to get the contribution of parameter in roundness.
Finally, this study will also produce the best parameter setting and also verify the most
effect parameter on roundness that need to be controlled. With this study and
implementation on the machine it can the quality of the roundness.
i
DEDICATION
For my beloved mother and father
ii
ACKNOWLEDGEMENT
First and foremost, I would like to express my highest appreciation to my
supportive supervisor, Mr Amri bin Sulaiman for his supervision and support in
completing this thesis.
Next I would like to dedicate my thankfulness and acknowledge to laboratory
technicians, who has been so warmth and kind to provide sincere assistance and good
cooperation during the training period. Their cooperation is much appreciated. . In
addition, I would like to convey thanks to Miss Liew Pay Jun for her assistance, which
really spends her time to teach me a lot of knowledge regarding to the DOE.
Last but not least, I would like to convey my appreciation to all the staff of
Faculty of Manufacturing Engineering, FKP, my friend and colleagues for their support
and their help in the project. Thank you.
iii
TABLE OF CONTENT
Abstract
i
Dedication
ii
Acknowledgement
iii
Table of content
iv
List of table
vii
List of figure
viii
CHAPTER 1 1
INTRODUCTION
1
1.1 OBJECTIVE
2
1.2 SCOPE
2
1.3 PROBLEM STATEMENT
3
CHAPTER 2
4
LITERATURE REVIEW
4
2.1 CNC lathe machine
5
2.1.1 CNC Lathe Machine Model Haas SL-20
5
2.1.2 Machine specification
7
2.1.3 Fundamental of CNC lathe cutting (Graham T.smith, 2002)
8
2.2 Roundness
8
2.2.1 Roundness measurement
9
2.2.1.1 Method in Measure Roundness
2.2.1.2
Least Square Method
9
11
2.3 Cutting Parameter
12
2.3.1 Feed Rate
12
2.3.2 Cutting speed
14
iv
2.3.2.1
Effect of Work Speed on Geometrical Characteristic
2.3.3 Depth of Cut
16
2.4 Material
16
2.4.1 Aluminum
2.4.1.1
14
16
Aluminum characteristic
17
2.4.2 Aluminum 6061
18
2.4.2.1
Chemical Composition for Aluminum 6061
18
2.4.2.2
Mechanical Properties
19
2.5 Design of Experiment (DOE)
19
2.5.1 DOE overview
19
2.5.2 Factorial design
20
2.5.3 Implementation of factorial design
21
2.6 Mahr Formtester MMQ44 (Mahr GmbH, 2007)
22
CHAPTER 3
24
METHODOLOGY
24
3.1 Flow Chart
25
3.2 Material
27
3.2.1 Material Selection
27
3.3 Machining Setup Parameters
27
3.3.1 Parameter Setup by Applying Two Level Factorial Method
27
3.3.2 Data Table
28
3.3.3 Methodology for DOE
29
3.4 CNC Lathe Machine Set-up
30
3.4.1 Specimens Preparation
30
3.4.2 Parameter Setting
31
3.4.3 Machining Procedure
31
3.4.4 Methodology of Machining Operation Using the CNC lathe machine
32
3.5 Analysis
32
3.5.1 Methodology of Roundness Measurement
32
3.5.2 Procedure to measure the roundness using CNC Roundness
33
v
3.6 Data Analysis
34
3.6.1 Design of Experiment (DOE)
35
3.7 Gantt Chart Of The Study For PSM 1
36
3.8 Gantt Chart Of The Study For PSM 2
37
CHAPTER 4
38
RESULT AND ANALYSIS
39
4.1 Result of roundness of Aluminum 6061
40
CHAPTER 5
45
DISCUSSION
45
5.1 Roundness Numerical result analysis
47
5.2 Roundness graphical result analysis
48
5.3 Finding from the result
50
CHAPTER 6
51
CONCLUSION
51
6.1 Conclusion
51
6.2 Recommendation
52
REFERENCES
53
APPENDICES
55
vi
LIST OF TABLE
2.1
The machine specification of CNC lathe machine Model SL-20
7
2.2
Cutting speed for various material
15
2.3
Mechanical properties for aluminum 6061
18
2.4
Example of 2k factorial design
22
3.1
The arrangement of the high and low using full Factorial design
28
3.2
The arrangement of the high and low value using full Factorial design
28
3.3
DOE matrix
35
3.4
Gantt chart of the study for Projek Sarjana Muda 1 (PSM 1)
36
3.5
Gantt chart of Projek Sarjana Muda 2 (PSM 2)
37
4.1
Roundness result for sample A
39
4.2
Roundness result for sample B
39
4.3
Optimum parameter effect
40
vii
LIST OF FIGURE
2.1
CNC lathe machine SL-20 Series
6
2.2
View for CNC lathe machine SL-20 series
6
2.3
The diagram shows the trace and Y, the distance from the spindle
center to the trace at the angle
9
2.4
Problem with plug gauge method
10
2.5
The least square circles diagram on roundness material
12
2.6
The cutting forces reduce with the increasing of cutting speed
16
2.7
Schematic diagram of the main feature of just one configuration
for roundness testing machine
23
3.1
The flow chart of the project
26
3.2
Provided Aluminum 6061 Dimension
27
3.3
Plan for DOE
30
3.4
The flow chart of machining methodology
32
3.5
The CNC Roundness – Formtester MMQ44 manufactured by Mahr at
the Metrology Laboratory
3.6
33
Work piece been placed on chuck and probe been place near the
work piece surface
34
4.1
Pareto chart of the effect for sample A
40
4.2
The Pareto Chart of the Effects for sample B
40
4.3
The Normal Probability Plot of the Effects for sample B
41
4.4
The Normal Probability Plot of the Effects for sample B
41
4.5
The Main Effects Plot (data means) for sample A
42
4.6
The Main Effects Plot (data means) for sample B
42
4.7
The Interaction Plot (data means) for sample A
43
4.8
The Interaction Plot (data means) for sample B
43
4.9
The cube plot (data means) for sample A
45
viii
4.10
The cube plot (data means) for sample B
45
5.1
Roundness average against number of experiment
47
5.2
Sample main effect plot for sample B
49
5.3
Sample interaction plot for sample B
49
ix
CHAPTER 1
INTRODUCTION
The purpose of this report is to study on three main controllable parameter that has to be
consider in CNC lathe in term of roundness. The three main parameters are speed, depth
of cut and feed rate. This study also determines which parameter has the big influence in
roundness. In order to get the result several work piece will go through machining
operation. The material that use is Aluminum 6161. During the operation the parameter
will be change in every sample. The parameter are been setup by applying the Design of
Experiment (DOE). After machining, the sample will be test using MAHr CNC
Roundness Tester Machine. After that, all the roundness result will be compare again
three parameters. From the result it will produce the standard parameter and from that
also can know the parameter that effects the most in roundness.
1
1.1
I.
OBJECTIVE
To investigate the contribution of feed rate, cutting speed and depth of cut in
CNC lathe machine.
II.
To analyzed the roundness of the finish product using CNC Roundness tester
machine
III.
To find the best parameter for aluminum 6061 and determine the relationship
between the parameter and the roundness using Design of Experiment (DOE)
IV.
To identify the parameter that effect the most in roundness
1.2
SCOPE
Scope of this project is conducting a machining operating using the CNC lathe machine
to study the parameter in term of roundness. The machine that be used is CNC Lathe
Machine Model Haas SL-20 manufactured by HAAS Automation Inc. The parameters
that involve in this analysis are depth of cut; cutting speed and feed rate are set followed
to the Design of Experiment (DOE).The material that used is solid cylinder aluminum
6061 with 30mm diameter. The other parameters are constant such as coolant and many
more. The roundness test will be using the Mahr Formtester MMQ44 at the metrology
lab and method that be used of each sample is least Square Circle Method. The result
analysis will be done base on Factorial Design analysis using Minitab software.
2
1.3
PROBLEM STATEMENT
Roundness is one of geometrical tolerance that needs to be maintain when machining
cylindrical part. To obtain good tolerance of roundness three controllable parameter
need to be controlled. The parameters are depth of cut, speed (rpm) and feed rate that is
setup by the operator in the program. However, the value of parameters depends on the
size of the work piece to be machined. These controllable parameters are usually
adjusted to get the fine quality of roundness.
Before this there are no appropriate parameters when cutting the aluminum 6061 in term
of roundness. Hence, this study will develop the appropriate parameter for the CNC
lathe machine model SL-20 for this material.
This experiment also tries to get which parameter that affects the most in cutting
aluminum 6061. There is previous research that related to this study and therefore on
this experiment try to verify those research.
3
CHAPTER 2
LITERATURE REVIEW
A literature review was conducted to gain knowledge about the roundness and parameter
that effect in roundness using CNC lathe. There were a lot of articles about the cutting
parameter and roundness but only the little is related with these researches. In additional
to the literature search done at the library, discussion with those familiar with this
project and gathered more articles from internet. Even the gathered research article is not
directly to this project, it still helping reader for understanding these researches and also
for their study. The literature review will include in the machine, roundness, material,
parameter, Design of Experiment and roundness tester.
4
2.1
CNC lathe machine
2.1.1 CNC Lathe Machine Model Haas SL-20
For this PSM project will use CNC lathe model SL-20 series from Haas Automation that
available in FKP laboratory. CNC lathes are designed to meet the needs of modern
machine shops, now and long into the future. The SL Series offers a wide range of
capacities, and our space-saving Big Bore option increases capacity further while
retaining the original footprint. The SL-20, with a max turning capacity of 10.3" x 20"
and an 8.3" chuck, has a bar capacity of up to 2.0".
SL- 20 high-performance turning centers also feature massive headstock castings with
symmetric ribs for rigidity and thermal stability; on-the-fly wyes-delta switching for
peak performance throughout the rpm range; and embedded chip trays and high-volume
coolant systems for efficient chip removal. For control features advanced tool
management, single-button features, 15-inch color LCD monitor and a USB port. With
this feature it raised CNC turning to new levels of reliability, ease and productivity.
To simplify the ordering process, first determine the size of lathe needed to meet job
requirements, and then select the options, such as a hydraulic tailstock, versatile live
tooling, the automated Servo Bar 300 bar feeder, or the Big Bore option for larger bar
capacity in the original footprint. Options may be ordered in pre-packaged groups, or
selected individually for a custom configuration (Haas Automation Inc. 2008).
5
Figure 2.1 : CNC lathe machine SL-20 Series(Haas Automation Inc. 2008).
Figure 2.2: View for CNC lathe machine SL-20 series (Haas Automation Inc. 2008).
6
2.1.2 Machine specification
Table 2.1: The machine specification of CNC lathe machine Model SL-20 (Haas Automation Inc. 2008).
MAIN SPINDLE
AVAILABILITY
TURNING
DIAMETERS
TURNING LENGTHS
MAXIMUM SWING
CHUCK DIAMETER
BAR CAPACITY
NOSE: A2-5
Standard
NOMINAL:--
MAXIMUM:--
NOMINAL:10.000
"
MAXIMUM:10.000 "
5.300 "
STANDARD:-MAXIMUM:-0.875
DRIVE MOTOR (HP): 8.0
HEADSTOCK - SPINDLE 1
NOSE: A2-6
BORE: 3.000 "
SPEED: 50 - 4000 RPM
DRIVE MOTOR (HP): 20.0
OPTIONS (top speed):
OPTIONS:
3400 RPM
30.0
5000 RPM
7000 RPM
RANGE: 1
INDEX INCREMENT (degrees): 0.001
DIRECTION
TURNING
DIAMETERS
TURNING LENGTHS
Horizontal
NOMINAL:8.000 "
MAXIMUM:8.200 "
NOMINAL:15.000
"
MAXIMUM:16.300 "
OPTION: 17.500
23.000 "
MAXIMUM SWING
CHUCK DIAMETER
BAR CAPACITY
STANDARD:8.300
"
STANDARD:2.000
"
MAXIMUM:10.000 "
MAXIMUM:2.500 "
MAX. NUMBER OF SIMULTANEOUS CUTTING TOOLS: 1
MACHINE NET WEIGHT(pounds):9000
7
2.1.3 Fundamental of CNC lathe cutting (Graham T.smith, 2002)
There are two main factors influence a cutting process, which are independent variables
and dependent variables. The dependent variables that are influences by changes in the
independent variables such as:
Force and energy dissipated in the cutting process.
Temperature rise in the workpiece, the chip, and the tool.
Wear and failure of the tool.
Surface finish produced on the workpiece after machining.
The major independent variables in the cutting process are follows:
2.2
Tool material, coating, and tool condition.
Tool shape, surface finish, sharpness.
Work pieces material, condition, and temperature.
Cutting parameter such as speed, feed rate, and depth of cut.
Cutting fluid.
The characteristic of machine tool, such as its stiffness and damping.
Work holding and fixtures.
Roundness
In all manufacturing process roundness is one of the important things. In order to get the
best roundness it affected by lot of factors like cutting tool, depth of cut, cutting speed,
feed rate, type of material, coolant and many more. Roundness or out of roundness can
be as the radial deviation of the actual profile from the ideal roundness. When the
parameters are not selected properly it will effect the roundness of the product. If the
8
speed increase and feed decreases, loss of precision in roundness tends to increase
(Engineering statistic handbook, 2007)
2.2.1 Roundness measurement
The measurement of roundness can be made by two ways. The first way is to use
Coordinate measuring machine (CMM) and the second one is using MAHr Roundness
Tester Machine. Using roundness tester machine the machine will compare the
roundness from the product with actual sample roundness result. Three measurement of
roundness were taken at different location.
2.2.1.1 Method in Measure Roundness
Measurements of roundness require 360° traces of the workpiece made with a turntabletype instrument or a stylus-type instrument. A least squares fit of points on the trace to a
circle define the parameters of noncircularity of the workpiece. A diagram of the
measurement method is shown below (Engineering statistic handbook, 2007).
Figure 2.3: The diagram shows the trace and Y, the distance from the spindle center to the trace at the
angle (Engineering statistic handbook, 2007)
9
They are four reference circles are internationally accepted for roundness measurements.
They are:
i. Maximum radius inscribing circle (MIC);[6] The MIC is the largest circle just
contained by the profile of a work piece. It is also known as the plug gauge circle and is
intended for shafts (Guru S.M and Tsai D.M, 1998).
A circle is drawn within all the data and is expanded until it is constrained by
three valleys (David Whitehouse, 2002).
The center obtains by this method need not to be unique (David Whitehouse,
2002).
For this method there is ambiguity if there are two equally good centers like
in the dumbbell shape (David Whitehouse, 2002).
Two maximum
circumscribing circles
of same amplitude but
different centers
Figure 2.4: Problem with plug gauge method (Engineering statistic handbook, 2007)
ii. Minimum radius circumscribing circle (MCC) (Guru S.M and Tsai D.M, 1998).
The MCC is the smallest circle that just contains the profile of a work piece.
It is also known as the ring gauge circle and is intended for holes (Guru S.M
and Tsai D.M, 1998).
A circle is drawn around all the data and then shrunk onto to the data to get
the minimum size circle (David Whitehouse, 2002).
This has to have just three point of contact between the data and the circle
(David Whitehouse, 2002).
10