Design, Development, And Fabrication Of Tyre Lug Wrench.
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
TO HAVE A NEW DESIGN ON THE EXISTING LUG WRENCH
Thesis submitted in accordance with the requirements of the National Technical College University of Malaysia for the Bachelor Degree of Manufacturing
Engineering in Manufacturing Process
By
MOHD FAIZ BIN ABD RAHIM
Faculty of Manufacturing Engineering April 2007
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UTeM Library (Pind.1/2005)
SULIT
TERHAD
TIDAK TERHAD
(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)
(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)
(TANDATANGAN PENULIS) Alamat Tetap:
No 5, Jalan Kekwa 1B, Bukit Beruntung,
48300, Rawang, Selangor
Tarikh: _______________________
Disahkan oleh:
(TANDATANGAN PENYELIA) Cop Rasmi:
Tarikh: _______________________ * Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah dan Sarjana secara penyelidikan, atau
BORANG PENGESAHAN STATUS TESIS*
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
JUDUL: TO HAVE A NEW DESIGN ON LUG WRENCH
SESI PENGAJIAN: 2/2006-2007
Saya _____________________________________________________________________
mengaku membenarkan tesis (PSM/Sarjana/Doktor Falsafah) ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:
1. Tesis adalah hak milik Universiti Teknikal Malaysia Melaka.
2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan untuk tujuan pengajian sahaja.
3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran antara institusi pengajian tinggi.
4. **Sila tandakan (√)
MOHD FAIZ BIN ABD. RAHIM
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FAKULTI KEJURUTERAAN PEMBUATAN
Rujukan Kami (Our Ref) : 17 Ogos 2005 Rujukan Tuan (Your Ref):
Pustakawan
Perpustakawan Universiti Teknikal Malaysia Melaka UTeM, Ayer Keroh
MELAKA. Saudara,
PENGKELASAN TESIS SEBAGAI SULIT/TERHAD
- TESIS SARJANA MUDA KEJURUTERAAN PEMBUATAN (PROSES PEMBUATAN): MOHD FAIZ BIN ABD. RAHIM
TAJUK: TO HAVE A NEW DESIGN ON LUG WRENCH.
Sukacita dimaklumkan bahawa tesis yang tersebut di atas bertajuk
“TO HAVE A NEW DESIGN ON LUG WRENCH” mohon dikelaskan sebagai terhad untuk tempoh lima (5) tahun dari tarikh surat ini memandangkan ia mempunyai nilai dan potensi untuk dikomersialkan di masa hadapan.
Sekian dimaklumkan. Terima kasih.
“BERKHIDMAT UNTUK NEGARA KERANA ALLAH”
Yang benar,
PROF DR. MD. DAN BIN MD. PALIL
Pensyarah,
Fakulti Kejuruteraan Pembuatan (Penyelia Bersama)
06-2332122
s.k. - Penyelia Utama:
En. Hadzley B. Abu Bakar
UNIVERSITI TEKNIKAL MALAYSIA MELAKA
Karung Berkunci 1200, Ayer Keroh, 75450 Melaka Tel : 06-233 2421, Faks : 06 233 2414
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DECLARATION
I hereby, declare this thesis entitled “Design on a new Lug Wrench” is the results of my own research except as cited in the reference.
Signature :
Author’s Name : MOHD FAIZ BIN ABD RAHIM
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APPROVAL
This thesis submitted to the senate of UTeM and has been accepted as partial fulfillment of the requirements for the degree of Bachelor of Manufacturing Engineering (Manufacturing Process). The members of the supervisory committee are as follow:
……… Main Supervisor
(Official Stamp and Date)
……….. Co – Supervisor
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ABSTRACT
Most of the people in Malaysia have their own transportation to shift around. The most popular one is totally, car. With the improved volume of cars on road each day, it shows that that kind of transportation has becoming crucial and a must in Malaysia. With a statistic like that, then the idea to improve the lug wrench comes about. The new design of lug wrench has to be easy in usage, ergonomics, and can solve the common problems for the available lug wrench in the market. The design has to be compact, so it will answer the problem from the mostly nowadays lug wrench that is not very space saver. Lug wrench which is used to loosen or tighten the lug nuts on car’s rim is compulsory for every car’s owner in case of emergency. For that, some research and findings has to be done about lug wrench and the cars rim composition. The idea on having a reduced torque lug wrench based on the questionnaire provided. Most of car owner has facing their main problem on lug nuts that are too tight to be loosened. So, with a 3:1 ratio on its input/output rotation, it will at least reduce the torque three times less theoretically. The epicylic gearing used is suitable in having such a compact design. The prototype built will be used in trial to show its compatibility in all sizes of cars rim. Methods such as Design for Manufactured (DFM) and Design for Assembly (DFA) are used for mass-productions.
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ABSTRAK
Di Malaysia, kebanyakan orang menggunakan kenderaan tertentu untuk bergerak dari satu tempat ke satu tempat. Tetapi, yang paling mendapat perhatian rakyat Malaysia ialah kereta. Dengan peningkatan jumlah kerata yang terdapat di jalan-jalan, menunjukkan yang kereta telah menjadi salah satu pengangkutan yang terpenting. Dari situlah lahirnya untuk mencipta sebuah pembuka nut tayar. Alat pembuka tayar tersebut haruslah mudah dikendalikan, ergonomik, dan dapat menyelesaikan kebanyakan masalah yang terdapat pada alat pembuka nut tayar sekarang. Rekabentuknya pula mestilah kompak agar tidak menggunakan ruang yang banyak pada kenderaan. Kegunaan utama alat pembuka nut tayar adalah untuk menggantikan tayar ketika kecemasan. Dengan itu, kajian perlu dilakukan mengenai alat pembuka nut tayar sedia ada termasuk komposisi tayar tersebut. Segala konsep-konsep yang telah dicadangkan adalah berdasarkan borang soal selidik yang telah diberi. Berdasarkan borang tersebut juga didapati masalah utama ketika membuka nut tayar adalah keaadaan nut yang terlalu ketat. Dengan itu, dengan rekabentuk mekanisme yang dapat mengurangkan jumlah putaran output secara nisbah 3:1 diharap dapat mengurangkan keseluruhan tenaga yang diperlukan ketika membuka tayar. Mekanisme penting dalam menghasilkan alat pembuka nut tayar ini adalah dengan penggunaan epicylic gear. Prototaip yang telah dihasilkan akan digunakan untuk menguji kebolehsesuaian alat tersebut ke atas kebanyakan saiz rim kereta. Kaedah-kaedah seperti Design for Manufactured (DFM) dan Design for Assembly (DFA) digunakan untuk memastikan ianya boleh dihasilkan secara komersial.
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ACKNOWLEDGEMENTS
Several people have contributed to this attempt. The following individuals provided valuable comments on earlier drafts of the work: Prof. Dr. Md. Dan B. Md. Palil as my supervisor, Mr Yuhazri as my co-supervisor, Mr Khairul Anwar B. Rahman as my second reader and others who have significantly help, whether directly or not, to the publication of this thesis. Special thanks to all the technical staff from the laboratories for their guidance such as Mr Nazri b Mokte from machine shop lab, Mr Ashari from machine shop, Mr Hairmi from CAD/CAM lab and also Mr Hisyam from machine shop. A very huge appreciation also would like to be given to all the academic staff and all the office staffs for their courage and support.
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DEDICATION
All of my dedication goes to,
My father, Abd Rahim B. Abd Rahman and my mother, Khairul Bariah Bt. Ishak My brothers, Faizal, Fadly, Faizul, and Fikry,
My grandfather, Hj Ishak B. Hj Surin and my grandmother, Hjh Latifah Bt. Hj Rahman Also to all my relatives and friends,
For;
All of your advices and supports, Thank You
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TABLE OF CONTENTS
ABSTRACT i
ABSTRAK ii
DEDICATION iii
ACKNOWLEDGEMENT iv
TABLE OF CONTENTS v
LIST OF FIGURES viii
LIST OF TABLES x
LIST OF SYMBOLS xi
LIST OF ABBREVIATIONS xii
1.
INTRODUCTION
11.1.Introduction 1
1.2.Objectives 2
1.3.Problem Statements 2
1.4.Scope/Methodology 3
2.
LITERATURE REVIEW
42.1.Definition of Lug Wrench 5
2.1.1. Common Wrench 5
2.1.2. Speacialized Wrench 5
2.1.3. Lug Wrench 7
2.2.Histories 8
2.3.Theory and Concept 10
2.3.1. Different Sizes of Rim tire 10
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2.3.3. Types of Lug Wrench on the Market 15
2.3.4. Ergonomics on Lug Wrench 17
2.3.5. Concept of Torque 19
2.3.6. Concept on Torque Multiplier 23
2.3.7. Epicyclic Gearing 27
2.4. Conclusion 29
3.
METHODOLOGY
303.1.Customer Requirement 30
3.2.Engineering Perspective 31
3.3.Methodology Flow Chart 32
3.3.1. Customer Requirements 33
3.3.2. Problem Statements 34
3.3.3. Proposal Sketching 34
3.3.4. Screening 38
3.3.5. Scoring 39
3.3.6. Results 40
3.4.Material Selection 45
3.4.1. Handle Bar 45
3.4.2. Housings 45
3.4.3. Gears 46
3.4.4. Input & Output Stub 47
3.8. Design for Manufacture 47
4.
RESULT AND DISCUSSION
494.1.Product’s Design Specification 50
4.1.1. Purpose 50
4.1.2. Special or New Features 51
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4.1.4. Market Suggestion 51
4.1.5. Relationship to Existing Product Line 51
4.1.6. Market Need 52
4.1.7. Cost 52
4.1.8. Environment 53
4.1.9. Safety 53
4.1.10.Standard 53
4.3. Suggestions or Recommendation 54
4.4. Final Design Analysis 54
4.4.1. Gears Calculation 54
4.4.2. Simple Torque Calculation 56
4.4.3 Work 57
4.4.5 Energy 57
4.4.6 Power 59
4.4.7 Gears Recalculated 60
4.5. Manufacturing Process 62
4.6. Assembly 63
4.7. Final Components 66
4.8. Overall Discussion 67
5.
CONCLUSION AND RECOMMENDATIONS
685.1.Conclusion 69
5.2.Recommendations 70
6. REFERENCES
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LIST OF FIGURES
NO. TITLE PAGE
2.1 Differences between bolt circle pattern 12
2.2 Basic dimension of a lug nut 16
2.3 Cross-shaped lug wrench 16
2.4 Foldable lug wrench 17
2.5 L shaped lug wench 17
2.6 (a)The ‘spring’ reaction with multiplier behave like a very stiff ‘spring’(b)
When multiplier achieve the maximum torque 29
2.7 Mechanism on Epicyclic gearing 30
2.8 Sample of rotation in Epicyclic gearing 31
3.1 Methodology Flow Chart 41
3.2 Questionnaire Form 38
3.3 Concept A 44
3.4 Concept B 44
3.5 Concept C 45
3.6 Concept D 46
3.7 Main Proposal of the revised AD concept 49
3.8 Concept Development on holder design 50
3.9 The basic shape of housing 51
3.10 Input Pinion 52
3.11 The picture of (a) Input Carrier (b) Dowell Pins 52
3.12 Planet Pinion with the input retainer 53
3.13 Output Stub 53
3.14 Special Screws 54
4.1 Orientation of Input Carrier on a Plat 69
4.2 Orientation of Holder on a Plat 69
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4.4 Input Carrier and Rods assembly 71
4.5 Gears applied 71
4.6 Housing and Internal Gear assembly (MIG welding) 72
4.7 Final Assembly 73
5.1 New Output Carrier 79
5.2 Applied force on existing Output Carrier 80
5.3 Applied force on new Output Carrier 80
5.4 New Input Carrier 81
5.5 Input Carrier with Gears 82
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LIST OF TABLES
NO. TITLE PAGE
2.1 Sample of lug nut sizes for car’s rim 15
3.1 Screening Method 47
3.2 Scoring method 48
3.3 Gear Selection 56
4.1 Components 59
4.2 Bill of Material 61
4.3 Final Components List 73
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LIST OF SYMBOLS
1. " inch
2. τ torque
3. π pie
4. θ angle
5. Σ sums
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LIST OF ABBREVIATIONS
1. mm millimeters
2. kg kilograms
3. in inch
4. PCD Pitch Circle Diameter
5. ft feet
6. lbs pound
7. N newton
8. m meter
9. Pa pascal
10. W weight
11. g gravity
12. E energy
13. r displacement length
14. F force
15. P power
` 16. T period
17. f frequency
18. rpm revolution per minute
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CHAPTER 1
INTRODUCTION
Having a car is a must nowadays. We need transport to travel from one place to another. There are a lot to be considered so the car will run smoothly and achieved the objective in going to the specified destination. Car maintenance, for example, is of the major factor in keeping the life span of the car. In addition, the car owner has to know the basic specification of their own vehicle. This include in having the basic knowledge about how to change the car’s tire.
To change car’s tire, it requires a very most minimum skill. Almost everyone can do it. To change tire, we need a proper tool. In this situation, we use lug wrench. Most of the cars today will be provided with their own lug wrench. There are several types of lug wrench available in the market. The most common lug wrench is the Cross and the L shape type. This is initially provided by the manufacturer when we buy a new car. All of these lug wrenches is actually quite ergonomics but it also requires strength in using it. Both types used the same method but the experts has said that it is better to use the cross shape.
Although it is recommended by experts, the cross shape lug wrench still requires a great strength to use it. So, from this problem, many manufacturers have come out with several solutions. The most popular one is using the torque multiplier, but in very compact shape. The system and concept of this torque multiplier will be discussed later.
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1.1 Objectives of Project
i. Study on the development of the lug wrench that is simple, easy to use, and available to be kept in average car’s boot
ii. To have a new design of the new lug wrench system and all the mechanism involved
iii. To have a new design that are able to be commercialized
1.2 Problem Statement
Everyone will be facing the problem while changing their own car’s tire. This is caused by the provided lug wrench by the manufacturer. It is designed to have the simplest material and cost used. Because of that, it is not very suitable for lug wrench when it comes to the simplest strength required in using it. Most of the provide lug wrench will requires each person to use a great strength before the nuts can be loosen. It is poorly effective when it comes to a weak person like a woman for example. A woman is actually has a lower strength compared to man. It can be imagined the force required to loosen up the nuts as most of the nuts are tighten by the impact wrench. As for example, when the nuts is tighten using impact wrench for about 100 N.m, the energy when we need to loosen it is not the same. It actually for at least two times energy required when it comes to loosen it. This is because of the nuts itself has its own force between the meshing thread. So, roughly, for a 100 N.m force when tightening the nuts, it requires at least 200 N.m of energy to loosen it. The other factor that makes the nuts are hard to loosen is the rust factor that actually will ended up with a loosen head of the nuts when we didn’t have enough force to loosen the nuts.
By all of the problems stated, it is very appropriate to have a new lug wrench that requires a small energy but provide a great energy on the output. This will become possible when we study on the torque multiplier and the mechanism of the Epicyclic gears that will be discussed later.
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1.3 Scope/Methodology
i. Literature review on the lug wrench available in the market nowadays
ii. Study on the suitable structure and the material involved on the available lug wrench
iii. To have a new design on the system used whether it is manual, mechanical, or automatic, or both
iv. To have a new design of lug wrench that easy to be kept in tool box v. Design and prototype fabrication of the multipurpose lug wrench
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CHAPTER 2
LITERATURE REVIEW
Conveniently enough, a lug wrench is a tool designed to loosen and tighten lug nuts. Lug nuts are responsible for keeping tire rims attached to the axles, which means they are usually kept very tight. Professional mechanics generally use pneumatic socket wrenches to accomplish this feat, guaranteeing that the lug nuts won't work themselves loose during normal driving. A lug wrench is designed to provide drivers with enough leverage to loosen lug nuts during a roadside emergency.
There are two common lug wrench designs drivers may encounter. One is a metal bar bent on the end nearest a socket wrench. The other common lug wrench configuration resembles a cross, with various socket wrenches on each arm.
Both provide enough leverage for a driver to loosen lug nuts, but many experts recommend the cross-shaped lug wrench for maximum leverage. The bent-arm lug wrench features a pry bar on the opposite end, however, which can make removing hub caps or other wheel covers much easier.
The lug wrench comes into play most often with a flat tire. The driver usually removes the spare tire, car jack and lug wrench from the trunk in order to replace the flat. Once the hubcap or wheel cover is pried off, the lug nuts are revealed.
The driver must loosen, but not remove, all of the lug nuts before jacking up the car. This involves placing the lug wrench over a lug nut and applying downward force
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until the nut breaks loose. Once the lug nut becomes loose enough to turn by hand, the driver repeats the process with the rest of the nuts. With a cross-shaped lug wrench, the driver should be able to apply both upward and downward pressure on the left and right arms. This additional torque is why many professionals prefer the cross-shaped lug wrench.
Great care must be taken not to strip out the socket of a lug wrench. If the end of a bent-arm lug wrench is not attached to the lug nut correctly, excessive force can damage the nut or the socket. A lug wrench made from softer metals may be less expensive than a drop-forged steel model, but it may not be able to handle the most stubborn lug nuts. It is not uncommon for car owners to replace the factory-provided lug wrench and car jack with higher quality tools from an auto supply store.
2.1 Definition of Lug Wrench
A wrench or spanner is a tool used to provide a mechanical advantage in applying torque to turn bolts, nuts or other hard-to-turn items. In American English, wrench is the standard term, while spanner refers to a specialized wrench with a series of pins or tabs around the circumference. (These pins or tabs fit into the holes or notches cut into the object to be turned.) In British English, spanner is the standard term. Hinged tools, such as pliers or tongs, are not generally considered wrenches.
2.1.1 Common Wrenches
i. Open-end wrench or Open-ended spanner: a one-piece wrench with a U-shaped opening that grips two opposite faces of the bolt or nut. This wrench is often double ended, with a different sized opening at each end. The ends are generally oriented at an angle of around 30 degrees to the longitudinal axis of the handle. This allows a greater range of movement in enclosed spaces by flipping the wrench over.
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ii. Box-end wrench, or Box spanner, or Ring spanner: a one-piece wrench with an enclosed opening that grips the faces of the bolt or nut. The recess is generally a six-point or twelve-point opening for use with nuts or bolt heads with a hexagonal shape. The twelve-point fits onto the fastening at twice as many angles, an advantage where swing is limited. Eight-point wrenches are also made for square shaped nuts and bolt heads. Box-ends are also often double-ended.
iii. Combination wrench or Combination spanner: a double-ended tool with one end being like an open-end wrench or open-ended spanner, and the other end being like a box-end wrench or ring spanner. Both ends generally fit the same size bolt.
iv. Flare-nut wrench or Tube wrench: used for gripping the nuts on the ends of tubes. The design is similar to a box–end wrench but with an opening to allow the wrench to fit over the tube
v. Socket wrench: a hollow cylinder that fits over one end of a nut or bolt head— may include a handle but usually used with various drive tools. It generally has either a six–point or twelve–point recess, may be shallow or deep, and may have a built-in universal joint. In addition, face driving sockets are available. These are more durable still, and have the ability to drive a range of hexagonal head sizes, with less risk of damaging the nut or bolt head than traditional "corner" drivers. The drive handles generally used are:
a) A break–over (or hinged) handle.
b) A ratchet handle (contains a mechanism which allows the socket to be turned without removing it from the nut or bolt).
c) A speed handle (sometimes called a crank handle).
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Sockets are often sold as a set containing a collection of sockets of various sizes and associated drive tools; usually including, as a minimum, extensions, a ratchet driver, and a universal joint. Sockets are also used with various power tools.
2.1.2 Specialized Wrenches
i. Spoke wrench or spoke key: a wrench with a clearance slot for a wire wheel spoke such as a bicycle wheel and a drive head for the adjustment nipple nut. ii. Tap wrench: a double–handled wrench for turning the square drive on taps
used in threading operations (cutting the female threads such as within a nut) or a precision reamer.
iii. Die wrench: A double–handled wrench for turning the dies used in threading operations (cutting the male threads such as on a bolt).
iv. Torque wrench: a socket wrench drive tool that measures the amount of rotational force applied to the socket—this may be indicated visually with a rod or dial or may simply slip when a set torque is exceeded. The torque wrench would also be categorized as a measuring tool.
v. Drum wrench: a tool commonly used to open bungs on large 55 gallon drums. vi. Lug wrench: a socket wrench used to turn lug nuts on automobile wheels. vii. Plumber wrench: a tool to screw (rotate with force) various pipes during
plumbing.
viii. Tuning wrench: a socket wrench used to tune some stringed musical instruments.
2.1.3 Lug Wrench
A lug wrench is a type of socket wrench used to turn lug nuts on an automobile wheel. The form commonly found in car trunks is an L-shaped metal rod with a socket wrench on the bent end and a prying tip on the other. The prying tip is mainly intended to remove hub caps or wheel covers that may be covering a wheel's lug nuts. Another
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2 1.1 Objectives of Project
i. Study on the development of the lug wrench that is simple, easy to use, and
available to be kept in average car’s boot
ii. To have a new design of the new lug wrench system and all the mechanism involved
iii. To have a new design that are able to be commercialized
1.2 Problem Statement
Everyone will be facing the problem while changing their own car’s tire. This is caused by the provided lug wrench by the manufacturer. It is designed to have the simplest material and cost used. Because of that, it is not very suitable for lug wrench when it comes to the simplest strength required in using it. Most of the provide lug wrench will requires each person to use a great strength before the nuts can be loosen. It is poorly effective when it comes to a weak person like a woman for example. A woman is actually has a lower strength compared to man. It can be imagined the force required to loosen up the nuts as most of the nuts are tighten by the impact wrench. As for example, when the nuts is tighten using impact wrench for about 100 N.m, the energy when we need to loosen it is not the same. It actually for at least two times energy required when it comes to loosen it. This is because of the nuts itself has its own force between the meshing thread. So, roughly, for a 100 N.m force when tightening the nuts, it requires at least 200 N.m of energy to loosen it. The other factor that makes the nuts are hard to loosen is the rust factor that actually will ended up with a loosen head of the
nuts when we didn’t have enough force to loosen the nuts.
By all of the problems stated, it is very appropriate to have a new lug wrench that requires a small energy but provide a great energy on the output. This will become possible when we study on the torque multiplier and the mechanism of the Epicyclic gears that will be discussed later.
(2)
1.3 Scope/Methodology
i. Literature review on the lug wrench available in the market nowadays
ii. Study on the suitable structure and the material involved on the available lug wrench
iii. To have a new design on the system used whether it is manual, mechanical, or automatic, or both
iv. To have a new design of lug wrench that easy to be kept in tool box v. Design and prototype fabrication of the multipurpose lug wrench
(3)
4
CHAPTER 2
LITERATURE REVIEW
Conveniently enough, a lug wrench is a tool designed to loosen and tighten lug nuts. Lug nuts are responsible for keeping tire rims attached to the axles, which means they are usually kept very tight. Professional mechanics generally use pneumatic socket wrenches to accomplish this feat, guaranteeing that the lug nuts won't work themselves loose during normal driving. A lug wrench is designed to provide drivers with enough leverage to loosen lug nuts during a roadside emergency.
There are two common lug wrench designs drivers may encounter. One is a metal bar bent on the end nearest a socket wrench. The other common lug wrench configuration resembles a cross, with various socket wrenches on each arm.
Both provide enough leverage for a driver to loosen lug nuts, but many experts recommend the cross-shaped lug wrench for maximum leverage. The bent-arm lug wrench features a pry bar on the opposite end, however, which can make removing hub caps or other wheel covers much easier.
The lug wrench comes into play most often with a flat tire. The driver usually removes the spare tire, car jack and lug wrench from the trunk in order to replace the flat. Once the hubcap or wheel cover is pried off, the lug nuts are revealed.
The driver must loosen, but not remove, all of the lug nuts before jacking up the car. This involves placing the lug wrench over a lug nut and applying downward force
(4)
until the nut breaks loose. Once the lug nut becomes loose enough to turn by hand, the driver repeats the process with the rest of the nuts. With a cross-shaped lug wrench, the driver should be able to apply both upward and downward pressure on the left and right arms. This additional torque is why many professionals prefer the cross-shaped lug wrench.
Great care must be taken not to strip out the socket of a lug wrench. If the end of a bent-arm lug wrench is not attached to the lug nut correctly, excessive force can damage the nut or the socket. A lug wrench made from softer metals may be less expensive than a drop-forged steel model, but it may not be able to handle the most stubborn lug nuts. It is not uncommon for car owners to replace the factory-provided lug wrench and car jack with higher quality tools from an auto supply store.
2.1 Definition of Lug Wrench
A wrench or spanner is a tool used to provide a mechanical advantage in applying torque to turn bolts, nuts or other hard-to-turn items. In American English, wrench is the standard term, while spanner refers to a specialized wrench with a series of pins or tabs around the circumference. (These pins or tabs fit into the holes or notches cut into the object to be turned.) In British English, spanner is the standard term. Hinged tools, such as pliers or tongs, are not generally considered wrenches.
2.1.1 Common Wrenches
i. Open-end wrench or Open-ended spanner: a one-piece wrench with a U-shaped opening that grips two opposite faces of the bolt or nut. This wrench is often double ended, with a different sized opening at each end. The ends are generally oriented at an angle of around 30 degrees to the longitudinal axis of the handle. This allows a greater range of movement in enclosed spaces by
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6
ii. Box-end wrench, or Box spanner, or Ring spanner: a one-piece wrench with an enclosed opening that grips the faces of the bolt or nut. The recess is generally a six-point or twelve-point opening for use with nuts or bolt heads with a hexagonal shape. The twelve-point fits onto the fastening at twice as many angles, an advantage where swing is limited. Eight-point wrenches are also made for square shaped nuts and bolt heads. Box-ends are also often double-ended.
iii. Combination wrench or Combination spanner: a double-ended tool with one end being like an open-end wrench or open-ended spanner, and the other end being like a box-end wrench or ring spanner. Both ends generally fit the same size bolt.
iv. Flare-nut wrench or Tube wrench: used for gripping the nuts on the ends of tubes. The design is similar to a box–end wrench but with an opening to allow the wrench to fit over the tube
v. Socket wrench: a hollow cylinder that fits over one end of a nut or bolt head— may include a handle but usually used with various drive tools. It generally has either a six–point or twelve–point recess, may be shallow or deep, and may have a built-in universal joint. In addition, face driving sockets are available. These are more durable still, and have the ability to drive a range of hexagonal head sizes, with less risk of damaging the nut or bolt head than traditional "corner" drivers. The drive handles generally used are:
a) A break–over (or hinged) handle.
b) A ratchet handle (contains a mechanism which allows the socket to be turned without removing it from the nut or bolt).
c) A speed handle (sometimes called a crank handle).
(6)
Sockets are often sold as a set containing a collection of sockets of various sizes and associated drive tools; usually including, as a minimum, extensions, a ratchet driver, and a universal joint. Sockets are also used with various power tools.
2.1.2 Specialized Wrenches
i. Spoke wrench or spoke key: a wrench with a clearance slot for a wire wheel spoke such as a bicycle wheel and a drive head for the adjustment nipple nut. ii. Tap wrench: a double–handled wrench for turning the square drive on taps
used in threading operations (cutting the female threads such as within a nut) or a precision reamer.
iii. Die wrench: A double–handled wrench for turning the dies used in threading operations (cutting the male threads such as on a bolt).
iv. Torque wrench: a socket wrench drive tool that measures the amount of rotational force applied to the socket—this may be indicated visually with a rod or dial or may simply slip when a set torque is exceeded. The torque wrench would also be categorized as a measuring tool.
v. Drum wrench: a tool commonly used to open bungs on large 55 gallon drums. vi. Lug wrench: a socket wrench used to turn lug nuts on automobile wheels. vii. Plumber wrench: a tool to screw (rotate with force) various pipes during
plumbing.
viii. Tuning wrench: a socket wrench used to tune some stringed musical instruments.
2.1.3 Lug Wrench
A lug wrench is a type of socket wrench used to turn lug nuts on an automobile wheel. The form commonly found in car trunks is an L-shaped metal rod with a socket wrench on the bent end and a prying tip on the other. The prying tip is mainly intended