Analyze The Performance Between Pure Oil-Based Coolant And Combination Of Oil-Based Coolant With Palm Oil On Cutting Surface In Milling Operation.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

ANALYZE THE PERFORMANCE BETWEEN PURE

BASED COOLANT AND COMBINATION OF

OIL-BASED COOLANT WITH PALM OIL ON CUTTING

SURFACE IN MILLING OPERATION

Thesis submitted in accordance with the requirements of the University Technical Malaysia Melaka for the Bachelor Degree of Manufacturing

Engineering in Manufacturing Process

Mohd Hafis Bin Bajuri

Faculty ofManufacturing Engineering March 2008

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APPROVAL

This thesis submitted to the senate of UTeM and has been accepted as partial fulfilment of the requirements for the degree of Bachelor of Manufacturing (Manufacturing Process). The members of the supervisory committee are as follow:

……… Supervisor

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DECLARATION

I hereby, declare this thesis entitled “Analyze The Performance Between Pure Oil-Based Coolant And Combination Of Oil-Oil-Based Coolant With Palm Oil On Cutting Surface In Milling Operation” is the result of my own research except as cited in the

references.

Signature : ………. Author’s Name : MOHD HAFIS BIN BAJURI

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UTeM Library (Pind.1/2007)

BORANG PENGESAHAN STATUS TESIS* UNIVERSITI TEKNIKAL MALAYSIA MELAKA

JUDUL:

SESI PENGAJIAN: 2007/ 2008

Saya _____________________________________________________________________ mengaku membenarkan t esis (PSM/ Sarj ana/ Dokt or Falsaf ah) ini disimpan di

Perpust akaan Universit i Teknikal Malaysia Melaka (UTeM) dengan syarat -syarat kegunaan sepert i berikut :

1. Tesis adalah hak milik Universit i Teknikal Malaysia Melaka.

2. Perpust akaan Universit i Teknikal Malaysia Melaka dibenarkan membuat salinan unt uk t uj uan pengaj ian sahaj a.

3. Perpust akaan dibenarkan membuat salinan t esis ini sebagai bahan pert ukaran ant ara inst it usi pengaj ian t inggi.

4. **Sila t andakan (√)

Analyze The Performance Between Pure Oil Based Coolant And Combination Of Oil Based Coolant With Palm Oil On Cutting Surface In Milling Operation.

MOHD HAFIS BIN BAJURI

Disahkan ol eh:

(TANDATANGAN PENULIS) Alamat Tet ap:

NO83, Sg. Tekam Ut ara, 27060 Jerant ut ,

Pahang.

Tarikh: 26 March 2008

(TANDATANGAN PENYELIA) Cop Rasmi:

Tarikh: 26 March 2008

* Tesis dimaksudkan sebagai t esis bagi Ij azah Dokt or Falsaf ah dan Sarj ana secara penyelidikan, at au (Mengandungi maklumat TERHAD yang t elah dit ent ukan oleh organisasi/ badan di mana penyelidikan dij alankan) (Mengandungi maklumat yang berdarj ah keselamat an at au kepent ingan Mal aysia yang t ermakt ub di dalam AKTA RAHSIA RASMI 1972)

TIDAK TERHAD TERHAD

√

SULIT

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA Karung Berkunci 1200, Ayer Keroh, 75450 Melaka

Tel : 06-233 2421, Faks : 06 233 2414 Email : fkp@kutkm.edu.my

FAKULTI KEJURUTERAAN PEMBUATAN

Rujukan Kami (Our Ref) : 26 March 2008

Rujukan Tuan (Your Ref):

Pust akawan

Perpust akawan Kolej Universit i Teknikal Kebangsaan Malaysia KUTKM, Ayer Keroh

MELAKA. Saudara,

PENGKELASAN TESIS SEBAGAI SULIT/ TERHAD

- TESIS SARJANA MUDA KEJURUTERAAN PEMBUATAN (PROSES PEMBUATAN): TAJUK:

Sukacit a dimaklumkan bahawa t esis yang t ersebut di at as bert aj uk “ Anal yze The Perf ormance Bet ween Pure Oil Based Coolant And Combinat ion Of Oil Based Cool ant Wit h Palm Oil On Cut t ing Surf ace In Milling Operat ion” mohon dikelaskan sebagai t erhad unt uk t empoh lima (5) t ahun dari t arikh surat ini memandangkan ia mempunyai nilai dan pot ensi unt uk dikomersialkan di masa hadapan.

Sekian dimaklumkan. Terima kasih.

“ BERKHIDMAT UNTUK NEGARA KERANA ALLAH”

Yang benar,

WAN HASRULNIZZAM WAN MAHMOOD

Pensyarah,

Fakul t i Kej urut eraan Pembuat an

(Penyel ia Bersama)

06-2332122

s. k. - Penyelia Ut ama:

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ABSTRACT

This paperwork will represent the performance analysis of coolant during milling operation. The analysis is focusing on the surface machining. Generally, there have been a few types of cutting fluid in market and the application of cutting fluid to the machining process will give a few advantages such as producing a good surface finish. The main purpose of this project is to investigate the performance of palm oil application as compound in coolant which is suitable for the machining operation especially the milling operation or not. Another purpose is to compare and identify the best coolant between the oil-based coolant and the combination of oil-based coolant with palm oil in the aspect of surface machining. The experiment is using a carbon steel AISI 1045 as a workpiece material with dimension of 100 x100 x 50. The workpiece is milled using conventional milling machine using bacteriostatic emulsifiable cutting oil (FUCHS) mixed with pure palm oil as the coolant. The parameters setting such as cutting speed is set differently, 100rpm, 200rpm, 300rpm, and 400rpm. The feed rate is 1mm/rev and depth of cut is 0.5mm remains constant. Surface roughness value is taken through the surface roughness tester and surface texture observation is done using metallurgy microscope. As the result, the palm oil compound will affect the surface machining and decrease the quality of surface machining. A few factor is identified that affect to the surface roughness which are cutting speed and machining time.

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ABSTRAK

Kertas kerja ini akan menerangkan tentang analisis prestasi pendingin semasa operasi jenis kisaran. Analisis adalah menumpukan kepada permukaan yang telah dimesin. Umumnya, terdapat pelbagai jenis bendalir pendingin dan aplikasinya dalam proses memesin akan memberi beberapa kelebihan seperti menghasilkan satu kemasan permukaan yang baik. Tujuan utama projek ini dijalankan adalah untuk menyiasat prestasi minyak sawit apabila dicampurkan ke dalam pendingin untuk mengetahui samada ianya sesuai atau tidak bagi tujuan pemesinan terutama untuk operasi mengisar. Tujuan lain projek ini adalah untuk membandingkan dan mengenal pasti pendingin terbaik antara minyak berasaskan pendingin sahaja atau gabungan minyak berasaskan pendingin dengan minyak sawit dalam aspek permukaan yang dimesin. Eksperimen ini menggunakan satu keluli karbon AISI 1045 sebaga bahan kerja berdimensi 100 x100 x 50. Bahan kerja akan dikisar menggunakan mesin kisar konvensional dengan aplikasi (FUCHS) bakteriostatik emulsifiable dicampur dengan minyak sawit murni sebagai pendingin. Parameter kelajuan seperti kelajuan memotong diaturkan secara berbeza- beza iaitu 100rpm, 200rpm, 300rpm, dan 400rpm. Kadar suapan adalah 1mm/rev dan kedalaman memotong adalah 0.5mm akan dikekalkan nilainya.Nilai kekasaran permukaan diambil terus daripada penguji kekasaran permukaan dan pemerhatian tekstur permukaan adalah dibuat menggunakan mikroskop metalurgi. Sebagai hasilnya, sebatian minyak sawit akan menjejaskan permukaan memesin dan mengurangkan kualiti permukaan yang dimesin. Beberapa faktor dikenalipasti akan memberi kesan kepada kekasaran permukaan yang adalah kelajuan memotong dan jumlah masa untuk memesin.

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ACKNOWLEDGEMENTS

Bismillahhirrahmanirrahim. Assalamualaikum

First of all, thank to ALLAH S.W.T for giving me the strength to complete this Project Sarjana Muda. Thank to my family for their support in every aspect.

Special thank to my supervisor, En. Ammar bin Abd. Rahman, and UTeM’s lecturer that helped and guided me throughout this project.

Last but not least, I would like to convey my appreciation to all the staff of Manufacturing Engineering Faculty, my friends and colleagues for their support and help in the project. Thank you.

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Abstract i

Abstrak ii

Acknowledgements iii

Table of Contents iv

List of Figures vii

List of Tables ix

List of Abbreviations, Signs, and Symbols x

CHAPTER 1: INTRODUCTION 1.1 Introduction 1

1.2 Problems Statements 3

1.3 Objectives of Project 3

1.4 Scope of Project 4

CHAPTER 2: LITERATURE REVIEW 2.1 Cutting Fluid 5

2.1.1 Principle of Cooling and Lubrication 5 2.1.2 Cooling Ability of Cutting Fluids 6 2.1.3 Types of Cutting Fluids 8

2.1.3.1 Straight Oil 8

2.1.3.2 Soluble Oil 8

2.1.3.3 Synthetic Fluid 8

2.1.3.4 Semi-synthetic Fluid 9

2.1.4 Cutting Fluid Selection Criteria 10

2.1.5 Cutting Fluid Application Methods 12

2.1.6 Benefits of Cutting Fluid 14

2.1.7 Cutting Fluid Health Hazards and Recycling 15 2.2 Palm Oil 16

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2.2.3 Palm Oil (Vegetables Oil) to Become Cutting Fluids 17

2.3 Introduction of Milling 18

2.3.1 Milling Operation 19

2.3.1.1 Face Milling 19

2.3.2 Method of Milling 19

2.3.2.1 Up Milling 19

2.3.3 Machining Parameter 20

2.3.3.1 Cuffing Speed, Depth of Cut and Feed Rate 20

2.4 Workpiece Materials 21

2.5 Cutting Tool 21

2.5.1 Cutting Tool Materials 21

2.5.2 High Speed Steel 22

2.6 Introduction of Surface 22

2.6.1 Roughness 23

2.6.2 Waviness 24

2.6.3 Surface Roughness 24

2.6.4 Method to Analyze Surface Roughness 24

2.6.4.1 Average Roughness (Ra) 24

CHAPTER 3: METHODOLOGY

3.1 Introduction 26

3.1.1 Project Planning 26

3.2 Items Selection for Project 30

3.2.1 Selection of Machine 30

3.2.2 Selection of Cutting Fluid 31

3.2.2.1 Bacteriostatic Emulsifiable Oil Coolant (FUCHS) 32 3.2.3 Selection of Additional Compound (Palm Oil) 33

3.2.4 Selection of Workpiece Material 33

3.2.5 Selection of Cutting Tool 34

3.2.6 Selection of Parameters 35

3.2.7 Selection of Method for Analysis 36

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3.2.7.2 Method to Observe the Surface Texture 37

3.3 Experiment Procedure 38

3.3.1 Experiment Flowchart 39

3.3.2 Coolant Preparation 39

3.3.3 Cutting Tool Preparation 40

3.3.4 Workpiece Preparation 40

3.3.5 Machining Parameter 40

3.3.6 Machining and Analysis Procedure 41

3.3.6.1 Milling Machine Procedure 41

3.3.6.2 Surface Roughness Tester (SJ-301) Procedure 42

3.3.6.3 Metallurgy Microscope Procedure 42

CHAPTER 4: RESULT

4.1 Introduction 43

4.2 Surface Roughness Analysis 44

4.2.1 Relationship between Surface Roughness and Machining Time 45 4.2.2 Relationship between Surface Roughness and Cutting Speed 46

4.3 Surface Texture Analysis 48

CHAPTER 5: DISCUSSION

5.1 Comparison of Surface Roughness Value 51

5.2 Comparison for Cutting Speed 52

5.3 Comparison for Machining Time 55

CHAPTER 6: CONCLUSION AND RECOMMENDATIONS

6.1 Conclusion 59

6.2 Further Work Recommendation 60

REFERENCES 61

APPENDIX A 65

APPENDIX B 66

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LIST OF FIGURE

Figure Description Page

2.1 Cooling curves of all fluids experiment 7

2.2 A flood method of cutting fluid is applied on the workpiece. 13 2.3 A jet method of cutting fluid is applied on the workpiece directed

at the cutting zone.

13 2.4 The mist application of cutting fluid is directed at the cutting

zone.

14 2.5 Milling operation consist slab, face, and end milling 19

2.6 Up milling 19

2.7 Roughness, Waviness, lay, and flaw. 23

2.8 Average Roughness (Ra). 25

3.1 Flow Chart for project 27

3.2 Conventional milling machine 31

3.3 FUCHS bacteriostatic emulsifiable coolant 32

3.4 Dimension of the workpiece 33

3.5 Carbon steel AISI 1045 workpiece 34

3.6 HSS cutting tool and tool holder 35

3.7 Portable Surface Roughness Tester: Model Surftest SJ – 301 36

3.8 Metallurgy Microscope 38

3.9 Flow chart for experiment procedure 39

4.1 Graph Surface Roughness Versus Machining Time 45 4.2 Graph Surface Roughness versus Cutting Speed 47 4.3 Surface Texture Image of Workpiece for Cutting Speed 100 rpm 48 4.4 Surface Texture Image of Workpiece for Cutting Speed 200 rpm 48 4.5 Surface Texture Image of Workpiece for Cutting Speed 300 rpm 49

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4.6 Surface Texture Image of Workpiece for Cutting Speed 400 rpm 49 5.1 Surface Roughness versus Machining Time for Cutting Speed

100 rpm

52 5.2 Surface Roughness versus Machining Time for Cutting Speed

200 rpm

53 5.3 Surface Roughness versus Machining Time for Cutting Speed

300 rpm

53 5.4 Surface Roughness versus Machining Time for Cutting Speed

400 rpm

54 5.5 Surface Roughness versus Cutting Speed for 5 minutes

machining

55 5.6 Surface Roughness versus Cutting Speed for 7.5 minutes

machining

55 5.7 Surface Roughness versus Cutting Speed for 10 minutes

machining

56 5.8 Surface Roughness versus Cutting Speed for 12.5 minutes

machining

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LIST OF TABLE

Table Description Page

2.1 General Characteristics of Cutting Fluid 9

2.2 Suitable type of cutting fluids depends to materials machining operation

2.3 Benefits of cutting fluid 14

2.4 Composition of Carbon steel AISI 1045 21

3.1 Gantt Chart Of The Study for Projek Sarjana Muda 1 (PSM 1) 28 3.2 Gantt Chart Of The Study for Projek Sarjana Muda 2 (PSM 2) 29

3.3 Milling Machine Specification 30

3.4 Cutting tool description 34

3.5 Parameters Setting 35

3.6 General specification of Mitutoyo Surface Roughness Tester 36

3.7 Experiment design 41

4.1 Surface Roughness Result for (FUCHS) Bacteriostatic Emulsifiable Coolant Mixed With Palm Oil

44 4.2 Surface Roughness Value, Ra for Variable Machining Time 45 4.3 Surface Roughness Value, Ra for Variable Cutting Speed 46

5.1 Surface Roughness Value for (FUCHS) bacteriostatic emulsifiable coolant mixed with palm oil and (FUCHS) bacteriostatic emulsifiable coolant only

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LIST OF ABBREVIATIONS, SIGNS, AND SYMBOLS

AISI - American Iron and Steel Institute BUE - built up edge

C - Carbon

Cu - Cooper

FKP - Fakulti Kejuruteraan Pembuatan HSS - high speed steel

in - inch

mm - millimetre (metric unit)

Mn - Manganese

P - Phosphorus PSM - Projek Sarjana Muda

Ra - arithmetic mean value (roughness average) Rpm - revolution per minute

Rq - root mean square average S - Sulfur

Si - Silicon

SEM - scanning electron microscopy

UTeM - Universiti Teknikal Malaysia Melaka USA - United State of America

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CHAPTER 1

INTRODUCTION

1.1 Introduction

Cutting fluids that is also called as coolant or lubricant are widely utilized to optimize the process of machining operations such as turning, milling, boring, grinding, and drilling. Historically, cutting fluids have been used extensively for the last 200 years. Today, it is estimated that over 100 million gallons of metalworking oil are used each year in the United States, and the volume of cutting fluids used is many times that of metalworking oil (Dilek Senay, 2001).

Nowadays, cutting fluids are very important in machining processes. It is used

extensively in machining as well as abrasive machining processes. It is used to reduce the detrimental effects of heat and friction on both tool and workpiece (Lopez de Lacalle, 2004). Cutting fluids are also used to carry away the heat in machining operations. This excessive heat can bring damage to the microstructure of metals. The metal removal rates can be increase by proper use of coolants. Another benefit of cutting fluid is to improve part quality and dimensional accuracy.

According to Kalpakjian (2001), the effectiveness in cutting operation depends on several numbers of factors such as the method used to apply the cutting fluid, temperature encountered, cutting speed and type of machining process. In machining, the energy that expended in cutting is transformed into heat. The deformation of the metal to create chips and the friction of the chip sliding across the cutting tool produce heat. The primary function of cutting fluids is to cool the tool, work piece, and chip. It also reduces friction at the sliding contacts and prevents the welding or

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adhesion on the contact edges that causes a built-up edge on the cutting tool or insert. Cutting fluids also help prevent rust and corrosion and flush chips away.

There is a wide variety of cutting fluids available today. Many new coolants have been developed to meet the needs of new materials, new cutting tools, and new coatings on cutting tools. The most common cutting fluids used today belong to one of two categories are oil-based fluids including straight oils and soluble oils and chemical fluids including synthetics and semi synthetics. Proper selection and use of cutting fluids can help to get good result in surface machining.

However, the usage of cutting fluid can also cause problem in a few cases. The direct contact of machines operator with cutting fluids may cause skin respiratory diseases. So now, new development is done to produce the friendly environmental cutting fluid. This type of cutting fluid use the vegetable oil based as compound in cutting fluid. It avoids the already problem those come from conventional cutting fluid. Now, the development of palm oil to be a cutting fluid is done. However, it just reached to the early stages. There are still more improvement must be done to achieve it.

This research is conducted to analyze the performance between pure oil based coolant and combination of oil-based coolant with palm oil on cutting surface in milling operation. The evaluations are defined from the experiment outcomes. All the findings from this study will prove that whether palm oil is suitable for use as cutting fluid especially in milling operation.

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1.2 Problems Statements

The problems that be based on this study are:

i. There are limited studies or information that exists regarding to the issue of

the palm oil as the cutting fluid in milling operation.

ii. The current coolants are harmful to the operator compared to the new formula

coolant based on vegetable oil (organic) like palm oil which is environmental friendly.

iii. There have no study proving that whether palm oil is a suitable solution to

mix with coolant. What happened if both of them are mixed?

1.3 Objectives of Project

In recognition the importance of coolant in machining, this project is tried to achieve the following objectives:

i. To study the performance between pure oil based coolant and combination of

oil based coolant with palm oil on cutting surface in milling operation.

ii. To analyze the surface roughness and observe the surface texture of the

surface machining that was produced on the workpiece from the usage of the oil-based coolant mix with palm oil and relating them with the parameters involves.

iii. To compare and identify the best coolant between the oil-based coolant and

the combination of oil-based coolant with palm oil in the aspect of surface machining.

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1.4 Scope of Project

This project is done to analyse the coolant application in milling operation in Manufacturing Laboratory of UTeM. The coolant to be used in this project is a bacteriostatic emulsifiable cutting oil. The bacteriostatic emulsifiable cutting oil has mixed with pure palm oil. This coolant afterwards is applied in face milling operation. All machining processes performed on carbon steel AISI 1045 with several parameters which are time of machining and cutting speed. This study will be focusing on the surface of machining consist of the surface roughness and surface texture. All of the samples will be analyzed using surface roughness tester and metallurgy microscope. The discussion will be done based on the result obtained.

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CHAPTER 2

LITERATURE REVIEW

2.1 Cutting Fluid

chip and tool interface, and chip removal (López de Lacalle et al., 2006). A cutting

fluid's effectiveness depends on factors such as the method used to apply the cutting fluid, temperatures encountered, cutting speed, and type of machining process (Kalpakjian, 1991). A fluid's cooling and lubrication properties are critical in decreasing tool wear and extending tool life. Cooling and lubrication are also important in achieving the desired size, finish and shape of the workpiece.

2.1.1 Principle of Cooling and Lubrication

Cooling give influences to machining in various ways. At the contact between the chip and tool, cooling can reduce the chip temperature. It also affects directly the friction force between the chip and tool. However, contact pressures are so high that the cutting fluid has no path by which it can completely penetrate the contact area.

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Cooling is mainly indirect via modified conduction through the chip. For the cutting edge, the coolant always plays a major role in maintaining the machined material at ambient temperature.

As coolers, cutting fluids decrease cutting temperature through the heat dissipation (cooling). When water based fluids are used, cooling is more important than lubrication. It was experimentally proved (Shaw, et al., 1951) that the cutting fluid efficiency in reducing temperature decreases with the increase of cutting speed and depth of cut.

As lubricant, the cutting fluid works to reduce the contact area between chip and tool and its efficiency depends on the ability of penetrating in the chip-tool interface and to create a thin layer in the short available time. This layer is created by either chemical reaction or physical adsorption and must have a shearing resistance lower than the resistance of the material in the interface. In this way it will also act indirectly as a coolant because it reduces heat generation and therefore cutting temperature (Sales et al., 2001).

2.1.2 Cooling Ability of Cutting Fluids

Aiming to classify the main cutting fluids based on their cooling ability, Sales (1999) developed a methodology which consisted in heating a standard workpiece and monitoring the cooling curve of it. This workpiece was fixed to the clutch of jigs and rotated at 150 rpm and its temperature was measured using an infrared sensor. The data acquisition started when the workpiece temperature reached 300°C and the measurement continued up to room temperature. Emulsions and synthetic fluids were applied using a concentration of 5%. Synthetic fluids are containing water and additives. The synthetic oil 1 is different from synthetic oil 2 due to small variations in their formulas (Sales et al., 2001). Figure 2.1 shows the results of this experiment.

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Figure 2.1: Cooling curves of all fluids experiment (Sales, 1999).

The cooling ability in crescent order is dry cutting, neat, oil emulsion, synthetic-2, water and synthetic-1. The fact that synthetic oil 1 presented a cooling ability greater than water, which theoretically has greater convection ability, was a surprise. A deeper analysis of the curves behavior in high temperature showed that water presented lower cooling ability even than synthetic oil 2 and neat oil (Sales et al., 2001).

The explanation of these results may be found on the phenomenon occurring when a fluid like water, with low ebullition point (100°C), starts contacting a body in high temperatures. At this moment the quick heat transfer causes the liquid evaporation. This process reduces a little the hot body temperature, but the vapor forms a barrier preventing fresh volume of liquid, from reaching its surface and, therefore, decreases the heat transfer efficiency. Another important factor is the fluid wet ability, which is regularly higher for cutting fluids than for water. The higher wet ability of the cutting fluid implies in less splashing action and therefore a greater chance for heat exchange (Sales et al., 2001).

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2.1.3 Types of Cutting Fluids

The main types of cutting fluids fall into two categories based on their oil content:

• Oil-Based Fluids - including straight oils and soluble oils

• Chemical Fluids - including synthetics and semi-synthetics

2.1.3.1 Straight Oil

Straight oils are non-emulsifiable and are used in machining operations in an undiluted form. They are composed of a base mineral or petroleum oil and often contain polar lubricants such as fats, vegetable oils and esters as well as extreme pressure additives such as Chlorine, Sulphur and Phosphorus. Straight oils provide the best lubrication and the poorest cooling characteristics among cutting fluids (Boothroyd and Knight, 2006).

2.1.3.2 Soluble Oil

Soluble Oil Fluids form an emulsion when mixed with water. The concentrate consists of a base mineral oil and emulsifiers to help produce a stable emulsion. They are used in a diluted form (usual concentration = 3 to 15%) and provide good lubrication and heat transfer performance. They are widely used in industry and are the least expensive among all cutting fluids (Boothroyd and Knight, 2006).

2.1.3.3 Synthetic Fluid

Synthetic Fluids contain no petroleum or mineral oil base and instead are formulated from alkaline inorganic and organic compounds along with additives for corrosion inhibition. They are generally used in a diluted form (usual concentration = 3 to 10%). Synthetic fluids often provide the best cooling performance among all cutting fluids (Boothroyd and Knight, 2006).

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2.1.3.4 Semi-synthetic Fluid

Semi-synthetic fluids are essentially combination of synthetic and soluble oil fluids and have characteristics common to both types. The cost and heat transfer performance of semi-synthetic fluids lay between those of synthetic and soluble oil fluids (Boothroyd and Knight, 2006).

Table 2.1: General Characteristics of Cutting Fluid (Nachtman and Kalpakjian, 1985).

Function Straight oils Soluble Oil Synthetic Fluids Semisynthetic fluids 1. Provide lubrication at high pressure (boundry lubrication)

1 2 3 4

2. Reduce heat fromplastic deformation (heat transfer)

5 2 2 1

3. Provide cushion between workpiece and tool (film thickness)

1 2 3 4

4. Reduce friction between tool and

workpiece

1 2 2 1 5. Reduce wear

between tool and workpiece

4 3 2 1 6. Protect

surface characteristic

5 2 2 1 7. Flushing

action to prevent buildup of scale (fluid flow)

5 4 3 2

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1.4 Scope of Project

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CHAPTER 2

LITERATURE REVIEW

2.1 Cutting Fluid

Cutting fluids play a critical role on metallic surfaces in cutting and forming operations. During the machining processes of a metal, a considerable quantity of heat is generated. It happens mainly due to the high plastic deformation in the primary shear zone and also to the friction of the chip on the surface. The condition of friction and temperature will cause tool wear. It also results in a poor surface finish and incorrect dimension. Cutting fluids are used to reduce the detrimental effects of heat and friction on both tool and workpiece. The cutting fluid produces three positive effects in the process whish are heat elimination, lubrication on the chip and tool interface, and chip removal (López de Lacalle et al., 2006). A cutting fluid's effectiveness depends on factors such as the method used to apply the cutting fluid, temperatures encountered, cutting speed, and type of machining process (Kalpakjian, 1991). A fluid's cooling and lubrication properties are critical in decreasing tool wear and extending tool life. Cooling and lubrication are also important in achieving the desired size, finish and shape of the workpiece.

2.1.1 Principle of Cooling and Lubrication

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Cooling is mainly indirect via modified conduction through the chip. For the cutting edge, the coolant always plays a major role in maintaining the machined material at ambient temperature.

2.1.2 Cooling Ability of Cutting Fluids

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Figure 2.1: Cooling curves of all fluids experiment (Sales, 1999).

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2.1.3 Types of Cutting Fluids

The main types of cutting fluids fall into two categories based on their oil content: • Oil-Based Fluids - including straight oils and soluble oils

• Chemical Fluids - including synthetics and semi-synthetics 2.1.3.1 Straight Oil

2.1.3.2 Soluble Oil

2.1.3.3 Synthetic Fluid

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2.1.3.4 Semi-synthetic Fluid

Table 2.1: General Characteristics of Cutting Fluid (Nachtman and Kalpakjian, 1985).

Function Straight oils Soluble Oil Synthetic Fluids Semisynthetic fluids 1. Provide lubrication at high pressure (boundry lubrication)

1 2 3 4

2. Reduce heat fromplastic deformation (heat transfer)

5 2 2 1

3. Provide cushion between workpiece and tool (film thickness)

1 2 3 4

4. Reduce friction between tool and

workpiece

1 2 2 1 5. Reduce wear

between tool and workpiece

4 3 2 1 6. Protect

surface characteristic

5 2 2 1 7. Flushing

action to prevent buildup of scale (fluid flow)

5 4 3 2

Analyze The Performance Between Pure Oil-Based Coolant And Combination Of Oil-Based Coolant With Palm Oil On Cutting Surface In Milling Operation.

UNIVERSITI TEKNIKAL MALAYSIA MELAKA