Design And Fabrication Of Self Centering Vice 31461z

DESIGN AND FABRICATION OF SELF CENTERING VICE A PROJECT REPORT Submitted by R.ARJUN

813814114011

A.DANIEL

813814114021

B.HARIHARAN

813814114035

K.MARUTHALOKESH

813814114306

A dissertation submitted in partial fulfillment for the award of the degree of BACHELOR OF ENGINEERING IN MECHANICAL ENGINEERING

SARANATHAN COLLEGE OF ENGINEERING, TIRUCHIRAPALLI.

ANNA UNIVERSITY CHENNAI 600 025 APRIL 2017

BONAFIDE CERTIFICATE

Certified this project report “DESIGN AND FABRICATION OF SELF CENTERING VICE” is the bonafide work of R.ARJUN

813814114011

A.DANIEL

813814114021

B.HARIHARAN

813814114035

K.MARUTHALOKESH

813814114306

who carried out the project work under my supervision.

SIGNATURE

SIGNATURE

Dr.G.JAYAPRAKASH

Mr.A.SARAVANAN

HEAD OF THE DEPARTMENT

SUPERVISOR

Mechanical Engineering,

Mechanical Engineering,

Saranathan College of Engineering

Saranathan College ofEngineering.

Trichy – 620012

Trichy – 620012

CERTIFICATE OF EVALUATION College Code

: 8138

College Name

: Saranathan College of Engineering, Tiruchirappalli

Branch

: Mechanical Engineering

Semester

: VI

S. No.

Number

Name of the Student

Title of the Project

1 2 3 4

813814114011 813814114021 813814114035 813814114306

R.ARJUN A.DANIEL B.HARIHARAN K.MARUTHALOKESH

DESIGN AND FABRICATION OF SELF CENTERING VICE

Name of the supervisor with designation Mr. A.SARAVANAN

The thesis of the project work submitted by the above students in partial fulfilment for the award of the degree of Bachelor of Engineering in Mechanical Engineering of Anna University, Chennai was confirmed to be the work done by the above students and then evaluatedon ____/____/____

INTERNAL EXAMINER

EXTERNAL EXAMINER

ACKNOWLEDGEMENT

We express our sincere thanks to Shri.S.Ravindran, Secretary, Prof. V. Nagarajan, Director and Dr.D.Valavan, M.Tech., Ph.d, Principal, Saranathan College of Engineering, for performing us to carry out this project. We are much obligated to Dr.G.Jayaprakash, M.E., Ph.d., Head of the Department, Department of Mechanical Engineering for his constant and encouragement. We express our sincere thanks to our project guide and project coordinator,Mr.A.Saravanan, Assistant Professor, Department of Mechanical Engineering for his constructive suggestions during the project fabrication and completion of the project.

We would like to thankful to our workshop instructor Mr.N.Paramasivam for his valuable throughout our project. We would like to thank to our staff and technical assistants for their and help rendered by them in completing this project successfully.

CONTENTS CHAPTER NO.

TITLE

Page No.

Abstract

i

List of Tables

ii

List of Figures

iii

Chapter 1

GENERAL INTRODUCTION 1.1 Assembly drawing

2

1.2 Detailing

3

1.3 Types of vice

6

1.4 Process Chart

11

Chapter 2

SELECTION OF MATERIAL 2.1 Nomenclature of twist drills

Chapter 3

Chapter 4

14

DESIGN AND FABRICATION WORK 3.1 Design calculation

22

3.2 Design process

27

3.3

32

Fabrication RESULTS AND DISCUSSION

4.1 Results

33

4.2 Advantages

36

4.3 Disadvantages

36

4.4 Applications

37

4.5 Future scope

38

4.6 Conclusion

38

4.7 References

39

ABSTRACT

This project mainly deals about design and fabrication of Self centering vice. The work consists of vice which is used to hold circular objects for drilling and machining operations. It is used when machining circular compounds. The work piece can be machined both horizontally and vertically based on the positioning of the vice. This type of vice is used for complicated jobs because it needs to be set horizontal and square planes before starting work. It is also used in slotting and planar machines. Specific operations such drilling and milling has been demonstrated.

i

LIST OF TABLES Chapter No. 4.1 Bill of Materials 4.2

TITLE

Page No. 34

Cost Estimation

35

ii

LIST OF FIGURES Chapter No. 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 2.1 3.1 3.2 3.3 3.4 3.5 3.6 3.7 4.1

TITLE Assembly diagram Front view Top view Side view Hydraulic power machine vice Accu-Lock Precision Machine vice Double action angle tight machine vice OH Milling Precision Machine vice Point angle 3D Drawing of assembly Base part V Block End plate Work piece Rectangular bar M12 Bolt Drilling operation using vice

iii

Page No. 2 3 4 5 7 8 9 10 18 28 28 29 29 30 30 31 33

1. INTRODUCTION

A vise or vice is a mechanical screw apparatus used for holding or clamping a work piece to allow work to be performed on it with tools such as saws, planes, drills, mills, screw drivers, sandpaper, etc. Vices usually have one fixed jaw and another parallel jaw which is moved towards or away from the fixed jaw by screw. Different types of vice are designed to accommodate different tasks. For instance, a metal working vice would not be ideal for professional wood working as it is designed to hold stronger materials and could possibly damage the wood. Vices can be separated into four categories: metal working, wood working, hand-held and machine.

1

1.1 ASSEMBLY DIAGRAM

Fig 1.1 Assembly diagram

2

1.2 DETAILING

Fig 1.2 Front View

3

Fig 1.3 Top view

4

Fig 1.4 Side view

5

1.3 TYPES OF VICE

Metal working vices: Metal working vices are mostly used for clamping metals, although they are the most versatile type of vice and can also be used to hole other materials, such as wood or plastic, if needed. Despite this, s should be careful when clamping wooden materials with a metal working vice, as the jaws can damage the appearance of the work piece. A metal working vice is usually mounted to the top of a workbench. Metal working vices are designed for strength when under pressure from heavy objects, such as steel bench blocks, and are available in a variety of different models and sizes for various tasks.

Wood working vices: Wood working vices are specifically used to clamp wood, not metal. Wood working vices differ from metal working vices as they are usually designed to mount underneath a workbench.

Hand-held vices: Hand-held vices are manually held tools for clamping or holding small objects while they are being worked on. They are ideal for holding small work pieces while completing intricate tasks, such as gluing or painting.

6

Hydraulic Power Machine Vise Performance and characteristics: characteristic 1. It is made of spheroidal cast iron. 2. The hardness of working surface is HRC50-60 3. The accuracy of vise (parallelism and squareness) is 0.025mm/100mm. 4. Resist bending in place of traditional clamping, it can produce strong campling by small pressure.

Fig 1.5 Hydraulic Power Machine Vise

Accu-Lock Precision Machine Vise Performance and characteristics: characteristic 1. It is made of spheroidal cast iron. 2. The hardness of working surface is HRC50-60. HRC50 3. The vise with angle lock devise can prevent work piece rising during operation. 4. The accuracy of vise (Parallelism and squareness) is 0.025mm/100mm. 7

5. The vise can be using with single or setting side by side on the machine table.

Applications:  It is widely used on machining center and other precision machine tools.

Fig 1.6 Accu-Lock Lock Precision Machine Vise

Double-action action Angle Tight Machine Vise Performance and characteristics: 1. It is made of spheroidal cast iron. 2. The hardness of working surface is HRC50-60. HRC50 4. It is possessed of two clamping positions. Two work pieces of same the vise or of different size can be clamped with are clamped in different positions and processed in different surfaces. 5. The Vise can be using with single or setting by side on the machine table.

Applications:  It is widely used on machining center and other precision machine tools.

8

Fig 1.7 Double-action Angle Tight Machine Vise

Delinble Machine Vise Performance and characteristics: 1. It is made of high-quality cast iron. 2. The accuracy of vise (Parallelism and squareness) is 0.025mm/100mm. 3. The vise body can be indexed through 90 degrees in vertical direction along large archaized guide way of swivel disc which can be indexed through 360 degrees in horizontal direction on the base.

Applications:  It is widely used on machine tool in making some kinds of slots, holes and faces.

9

Fig 1.8 OH Milling Precision Machine Vise

OH Milling Precision Machine Vise Performance and characteristics: 1. It is made of high-quality cast iron. 2. The accuracy of vise (parallelism and squareness) is 0.025mm/100mm.

Applications:  It is widely used on milling, planning and drilling machine tools  In making some kinds of slots, holes and faces.

10

1.4 PROPOSED METHODOLOGY Start

Selection of Material

Design Process

3D Drawing of Individual parts

Assembly of Individual parts

Design calculations

Summary of calculations

Fabrication work

Stop

11

2. SELECTION OF MATERIAL Mild steel Steel is made up of carbon and iron, with much more iron than carbon. In fact, at the most, steel can have about 2.1 percent carbon. Mild steel is one of the most commonly used construction materials. It is very strong and can be made from readily available natural materials. It is known as mild steel because of its relatively low carbon content. Mild steel contains approximately 0.05–0.25% carbon making it malleable and ductile. Mild steel has a relatively low tensile strength, but it is cheap and easy to form;surface hardness can be increased through carburizing. This type of steel is a very popular metal and one of the cheapest types of steel available. It’s found in almost every metal product. This type of steel contains less than 2 percent carbon, which makes it magnetize well. Since it’s relatively inexpensive, mild steel is useful for most projects requiring huge amounts of steel. Mild steel does not have great structural strength, making it unsuitable for building girders or structural beams. It is very strong due to the low amount of carbon it contains. In materials science, strength is a complicated term. It has a high resistance to breakage. Mild steel, as opposed to higher carbon steels, is quite malleable, even when cold. This means it has high tensile and impact strength. Higher carbon steels usually shatter or crack under stress, while mild steel bends or deforms. Mild steel has a density of .248 pounds per cubic inch. It melts at 2,570 degrees Fahrenheit. It has a specific heat of around .122 British Thermal Units (BTU) per pound, per cubic inches. 12

Materials Many different materials are used for or on drill bits, depending on the required application. Many hard materials, such as carbides, are much more brittle than steel, and are far more subject to breaking, particularly if the drill is not held at a very constant angle to the workpiece, e.g. when hand-held. Steels  Soft low carbon steel bits are inexpensive, but not hold an edge well and require frequent sharpening. They are used only for drilling wood; even working with hardwoods rather than softwoods can noticeably shorten their lifespan.  Bits made from high carbon steel are more durable than low-carbon steel bits due to the properties conferred by hardening and tempering the material. If they are overheated (e.g., b frictional heating while driling) they lose their temper, resulting in a soft cutting edge. These bits can be used on wood or metal.  High speed steel (HSS) is a form of tool steel; Hss bits are hard, and much more resistant to heat than high carbon steel. They can be used to drill metal, hardwood, and most other materials at greater cutting speeds than carbon steel bits, and have largely replaced carbon steels.  Cobalt steel alloys are variations on high speed steel which contain more cobalt. They hold their hardness at much higher temperatures, and are used to drill stainless steel and other hard materials. The main disadvantage of cobalt steels is that they are more brittle than standard HSS.

13

Others  Tungsten carbide and other carbides are extremely hard, and can drill virtually all materials while holding an edge longer than other bits. The material is expensive and much more brittle than steels; consequently they are mainly used for drill bit tips, small pieces of hard material fixed for brazing onto the tip of a bit made of less hard metal. However, it is becoming common in job shops to use soled carbide bits. In very small sizes it is difficult to fit carbide tips; in some industries, most notably PCB manufacturing, requiring many holes with diameters less than 1 mm, carbide bits are used.  Polycrystalline diamond (PCD) is among the hardest of all toll materials and is therefore about 0.5mm (0.019”) thick, bonded as a sintered mass to a tungsten carbide . Bits are fabricated using this material by either brazing small segments to the tip of the tool to form the cutting edges, or by sintering PCD into a vein in the tungsten carbide “nib”. The nib can later be brazed to a carbide shaft; it can then be ground to complex geometries that would otherwise cause braze failure in the smaller “segments”. PCD bits are typically used in the automotive, aerospace, and other industries to drill abrasive aluminum alloys, carbon fiber reinforced plastics, and other abrasive materials, and in applications where machine downtime to replace or sharpen worn bits is exceptionally costly.

2.1NOMENCLATURE OF TWIST DRILLS AND OTHER RELATING TO DRILLING Axis: The imaginary straight line which forms the longitudinal center line of the drill.

14

Back Taper: A slight decrease in diameter from front to back in the body of the drill. Body: The portion of the drill extending from the shank or neck to the outer corners of the cutting lips. Body Diameter Clearance: That portion of the land that has been cut away so it will not rub against the walls of the hole. Built-Up Edge: An adhering deposit of nascent material on the cutting lip or the point of the drill. Cam Relief: The relief from the cutting edge to the back of the land, produced by a cam actuated cutting tool or grinding wheel on a relieving machine. Chip Breaker: Nicks or Grooves designed to reduce the size of chips; they may be steps or grooves in the cutting lip or in the leading face of the land at or adjacent to the cutting lips. Chip Packing: The failure of chips to through the flute during cutting action. Chipping: The breakdown of a cutting lip or margin by loss of fragments broken away during the cutting action. Chisel Edge: The edge at the end of the web that connects the cutting lips Chisel Edge Angle: The angle included between the chisel edge and the cutting lip, as viewed from the end of the drill. Clearance: The space provided to eliminate undesirable between the drill and the workpiece. Clearance Diameter: The diameter over the cut away portion of the drill lands. Crankshaft or Deep Hole Drills: Drills designed for drilling oil holes in crankshafts, connecting rods and similar deep holes; they are generally made with heavy webs and higher helix angles than normal. Cutter Sweep: The section formed by the tool used to generate the flute in leaving the flute.

15

Double Margin Drill: A drill whose body diameter clearance is produced to leave more than one margin on each land and is normally made with margins on the leading edge and on the heel of the land. Drift: A flat tapered bar for forcing a taper shank out of its socket. Drift Slot: A slot through a socket at the small end of the tapered hole to receive a drift for forcing a taper shank out of its socket. Drill Diameter: The diameter over the margins of the drill measured at the point. Exposed Length: The distance the large of a shank projects from the drive socket or large end of the taper ring gage. External Center: The conical point on the shank end of the drill. And the point end on some sizes of core drills. Flat Drill: A drill whose flutes are produced by two parallel or tapered flats. Flat (Spade) Drill: A removable cutting drill tip usually attached to a special holder designed for this purpose; generally used for drilling or enlarging cored holes. Flutes: Helical or straight grooves cut or formed in the body of the drill to provide cutting lips, to permit removal of chips, and to allow cutting fluid to reach the cutting lips. Flute Length: The length from the outer corners of the cutting lips to the extreme back end of the flutes; it includes the sweep of the tool used to generate the flutes and, therefore, does not indicate the usable length of the flutes. Gage Line: The axial position on a taper where the diameter is equal to the basic large end diameter of the specified taper. Galling: An adhering deposit of nascent work material on the margin adjacent to the leading edge at and near the point of a drill. Guide: A cylindrical portion, following the cutting portion of the flutes, acting as a guide to keep the drill in proper alignment; the guide portion may be fluted, grooved, or solid. 16

Gun Drill: Special purpose straight flute drills with one or more flutes used for deep hole drilling; they are usually provided with coolant ages through the body. Half-Round Drill: A drill with a transverse cross-section of approximately half a circle and having one cutting lip. Heel: The trailing edge of the land. Helical Flutes: Flutes which are formed in a helical path around the axis. Helix Angle: The angle made by the leading edge of the land with a plane containing the axis of the drill. Land: The peripheral portion of the body between adjacent flutes. Land width: The distance between the leading edge and the heel of the land measured at a right angle to the leading edge. Lead: The axial advance of a leading edge of the land in one turn around the circumference. Lips: The cutting edges of a two flute drill extending from the chisel edge to the periphery. Lip Relief: The axial relief on the drill point. Lip Relief Angle: The axial relief angle at the outer corner of the lip; it is measured by projection into a plane tangent to the periphery at the outer corner of the lip. Margin: The cylindrical portion of the land which is not cut away to provide clearance. Multiple-Margin Drill: A drill whose body diameter clearance is produced to leave more than one margin in each land. Neek: The section of reduced diameter between the body and the shank of a drill. Oil Grooves: Longitudinal straight or helical grooves in the shank, or grooves in the lands of a drill to carry cutting fluid to the cutting lips Oil Holes or Tubes:

17

Holes through the lands or web of a drill for age of cutting fluid to the cutting lips. Overall Length: The length from the extreme end of the shank to the outer corners of the cutting lips; it does not include the conical shank end often used on straight shank drills, nor does it include the conical cutting point used on both straight and taper shank drills. Periphery: The outside circumference of a drill. Peripheral Rake Angle: The angle between the leading edge of the land and an axial plane at the drill point. Pilot: A cylindrical portion of the drill body preceding the cutting lips; it may be solid, grooved, or fluted. Point: The cutting end of a drill, made up of the ends of the lands and the web; in form it resembles a cone, but departs from a true cone to furnish clearance behind the cutting lips.

Fig 2.1 Point angle Point Angle: The angle included between the cutting lips projected upon a plane parallel to the drill axis and parallel to the two cutting lips. 18

Relative Lip Height: The difference in indicator reading on the cutting lip of the drill; it is measured at a right angle to the cutting lip at a specific distance from the axis of the tool. Relief: The results of the removal of tool material being are adjacent to the cutting lip and leading edge of the land to provide clearance and prevent rubbing (heel drag). Shank: The part of the drill by which it is held and driven. Sleeve: A tapered shell designed to fit into a specified socket and to receive a taper shank smaller than the socket. Socket: The tapered hole in a spindle, adaptor, or sleeve, designed to receive, hold, and drive a tapered shank. Step Drill: A multiple diameter drill with one set of drill lands which are ground to different diameters. Straight Flutes: Flutes which form lands lying in an axial plane. Sub land Drill: A type of multiple diameter drill which has independent sets of lands in the same body section for each diameter. Tang: The flattened end of a taper shank, intended to fit into a driving slot in a socket. Tang Drive: Two opposite parallel driving flats on the extreme end of a straight shank. Taper Drill: A drill with part or all of its cutting flute length ground with a specific taper to produce tapered holes; they are used for drilling the original hole or enlarging an existing hole. Taper Square Shank: A taper shank whose cross section is square. Web: The central portion of the body that s the lands; the extreme end of the web forms the chisel edge on a two-flute drill. Web Thickness: The thickness of the web at the point, unless another specific location is indicated.

19

Web Thinning: The operation of reducing the web thickness at the point to reduce drilling thrust. MILLING CUTTER: Milling Cutters are cutting tools typically used in milling machines or machining centre (and occasionally in other machine tools). They remove material by their movement within the machine (e.g., a ball nose mill) or directly from the cutters shape (e.g., a form tool such as hobbing cutter) Features of A MILLING CUTTER: Milling cutters come in several shapes and many sizes. There is also a choice of coatings, as well as rake angle and number of cutting surfaces. Shape: Several standard shapes of milling cutter are used in industry today, which are explained in more detail below. Flutes/teeth: The flutes of the milling bit are the deep helical grooves running up the cutter, while the sharp blade along the edge of the flute is known as the tooth. The tooth cuts the material, and chips of this material are pulled up the flute by the rotation of the cutter. There is almost always one tooth per flute, but some cutters milling cutters may have from one to many teeth, with 2,3,4 being most common. Typically, the more teeth a cutter has, the more rapidly it can remove material. So a 4 tooth cutter can remove material at twice the rate of a 2 tooth cutter. Helix Angle: The flutes of a milling cutter are almost always helical. If the flutes were straight, the whole tooth would impact the material at once, causing vibration and reducing accuracy and surface quality. Setting the flutes at an angle allows the tooth to enter the material gradually, reducing vibration. Typically finishing cutters have a higher rake angle to give a better finish Center Cutting: Some milling cutters can drill straight down through the material, while others cannot. This is because the teeth of some cutters do not 20

go all the way to the end face. However, these cutters can cut downwards at an angle of 45o or so. Roughing or Finishing: Different types of cutter are available for cutting away large amounts of material, leaving a poor surface finish, or removing a smaller amount of material, but leaving a good surface finish. A roughing cutter may have serrated teeth for breaking the chips of material into smaller pieces. These teeth leave a rough surface being. A finishing cutter may have a large number of flutes leaves little room for efficient swarf removal, so they are less appropriate for removing large amounts of material. Coatings: The right tool coatings can have a great influence on the cutting process by increasing cutting speed and tool life, and improving hard coating used on cutters which must withstand high abrasive wear. A PCD coated tool may last up to 100 times longer than an uncoated tool. However the coating cannot be used at temperatures above 600o or on ferrous metal. Tools for machining aluminum are sometimes given a coating of tialn. Aluminum is a relatively sticky metal, and can weld itself to the teeth of tools, causing them to appear blunt. However it tends not to stick to tialn, allowing the tool to be used for much longer in aluminum. Shank: The shank is the cylindrical part of the tool which is used to hold and locate it in the holder. A shank may be perfectly round, and held by friction, or it may have a Weldon Flat, where a grub screw makes for increased torque without the tool slipping. The diameter may be different from the diameter of the cutting part of the tool, so that it can be held by a standard tool holder.

21

3. DESIGN AND FABRICATION WORK 3.1 DESIGN CALCULATION Cutting Force (Drilling) FC=Ps x MRR/v (N)

(eqn 3.1)

Where PS=Specific Power=6.777x10-2 kW min/mm3 (For Mild Steel) MRR=( D2/4)Fr x N

(eqn 3.2)

Fr=Feed Rate(mm/min) =1.8 N=Drill Speed (rpm) = 1220 D=Drill Diameter (mm) = 6 v= DN (mm/min) = 22984.8 mm/min (peripheral velocity) MRR=( D2/4) x Fr x N=(3.14x36/4) x1.8x1220 = 6205.896 FC =PS x MRR/v=(6.777 x 10-2 x 6205.896)/22984.8 FC=180.279N Cutting Force (Milling) The 3 components of the cutting force Axial component of force, PX: 0.15PZ

(eqn 3.3)

Radial component of force, PY: 0.45PZ Tangential force, PZ: 6120N/V

(eqn 3.4) (eqn 3.5)

Drill diameter, d: 0.012 m Spindle Speed, n: 360 rpm where, N: power at spindle in kW V: cutting speed in m/min 22

Cutting Speed, V= dn/1000 m/min

(eqn 3.6)

V= x 0.012 x 360/1000 V=13.572 x 10-3m/min Power at the spindle, N = UKhKQ

(eqn 3.7)

Where, U - Unit power in kW/cm3/min Kh - Correction factor for flank wear K - Correction factor for radial rake angle Q - Material removal rate in cm3/min To find ‘U’ we need average chip thickness, as which is given by, Average chip thickness, c=114.6 x SZ x t/(s x D)

(eqn 3.8)

Where, SZ : feed per tooth (mm per tooth) From DDB Pg.No.12.29 for Mild Steel workpiece and HSS cutter Sz is given by 0.15 mm per tooth. t : depth of cut (2 mm) D: cutter diameter (12 mm) s : angle of with the workpiece in degree.

23

ANGLE OF WITH WORKPIECE Average chip thickness, c= 114.6 x 0.15 x 2/(48.19 x 12) c=0.0595 mm. Then, Unit power, U for average chip thickness and U=45 x 10-3 kW/cm3/min (Mild Steel) Kh= 1.18. K = 0.15 Metal removal rate, Q=btSm/1000 cm3/min

(eqn 3.9)

Where, b: width of cut= t/sin x

(eqn 3.10)

Sine of approach angle x can be calculated using the relation, sin x=c/SZ sin x= 0.0595/0.15 sin x= 0.9367 So, b= 2/0.3967 b= 5.042 mm. Feed per minute, Sm=SZ x Z x n

(eqn 3.11)

Sm= 0.15 x 360 x 4 Sm= 216 mm/min. Then, Q=5.42 x 2 x 0.216 24

Q=2.1782cm3/min. So, Power at the spindle, N=UKhK Q

(eqn 3.12)

N=45 x 10-3 x 1.18 x 0.93 x 2.1782 N=0.1076kW. Tangential force PZ = 6120 x N x 9.81/V = 6120 x 0.1076 x 9.81/13.572 PZ= 475.98 Newton. Axial component of cutting force, PX=0.15Pz=0.15 x 475.98 PX=71.397 N Radial component of cutting force, PY=0.15Pz=0.15 x 475.98 PY=214.191N Resultant cutting force, PR = (PX2 + PY2 +PZ2) ½

(eqn 3.13)

PR = (475.982 + 71.3972 + 214.1912) ½ PR = 526.813 N

25

Clamping Force Clamping force, Pcl = PRx Factor of Safety/Co-efficient of friction (eqn 3.14) Pcl = 526.813 x 1.3/0.3 Pcl = 2282.88 N From above calc Clamping Force is greater than Cutting Force (Milling and Drilling) Hence Design is Safe.

Maximum Bending Stress Assume Cantilever Beam and ping load acting on it so Max.Bending Stress of Side Plates can be calculated by Max Bending Stress,q = M/(bd2/6) (N/mm2)

(eqn 3.15)

Where, M=Max Bending moment = P x L (N-mm)

(eqn 3.16)

P = Load applied (N) = 228288 N L=length of the beam (mm) = 290mm b=175mm d=36mm Max Bending Stress, q = M/(bd2/6) = (2282.88 x 290) / (175 x 36 x 36/5) q = 17.43 N/mm2 < 190 N/mm2 From above calc design bending stress is less than the permissible stress Hence Design is Safe.

26

3.2DESIGN PROCESS Start

Design of Base

Design of lead screw

Design of V Block

Design of End plates

Design of Bolts & Nuts

Design of work piece (cylindrical object)

Assembly of all the part drawings

Stop

27

Fig 3.1 3D Drawing of Assembly

Fig 3.2 Base part

28

Fig 3.3 V Block

Fig 3.4 End plate

29

Fig 3.5 Work piece

Fig 3.6 Rectangular bar

30

Fig 3.7 M12 Bolt

31

3.3 FABRICATION The base plate and rectangular bars are welded. Right side tail end part is welded with base. Lead screw is made by using threading. V-block is made using notching on a T-shaped bar. Drilling and boring is done on the end of the V-block. Internal threading is done on bottom end of the V-block. Drilling is done on the left face of rectangular bar and left side of the tail end. Tapping is also done on the drilled portion of the rectangular bar.

32

4. RESULTS AND DISCUSSION 4.1 Results:

Fig 4.1 Drilling operation using vice Thus the self centering vice has been manufactured successfully. The vice has been installed in the upright drilling machine and drilling operation has been performed in the workpiece.

33

Table 4.1 BILL OF MATERIALS S.No

MATERIAL

SIZE

QTY

01

Base Plate

300mm x 300mm

1

02

Side Plate

100mm x 100mm

2

03

Mild Steel (Job)

40mm x 40mm

1

04

Bolt and Nuts

M12

4

05

Pin

M12

1

34

Table 4.2 COST ESTIMATION S.No

COMPONENT

DESCRIPTION QUANTITY

COST (IN RUPEES)

01

M.S. Plate

02

M.S. Plate

03

M.S. Plate

04

300 mm x

1

660

2

200

40 mm x 40mm

1

60

Bolt And Nut

M12

4

80

05

M.S. Pin

M12

1

20

06

----------

----------

Total

1170

300mm 100 mm x 100mm

35

4.2 ADVANTAGES  Portable one  Can be fixed at anywhere  Holding cylindrical workpieces rigidly  Workpieces can be easily holded as it is a self centering vice.  It saves time when fitting the work piece in the vice.  Reduction in center marking time

4.3 DISADVANTAGES

 It is not strong enough for heavy-duty clamping.  Risk of vibration or moving during work.  Portable vices with an integrated clamp may not fit on to all surface edges.

36

4.4 APPLICATIOINS  Self centering vice can be used for drilling and milling operations.  It is used to drill the hole in both horizontal and vertical directions.  It can also be installed in slotting machine.

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4.5 FUTURE SCOPE:  Tapered milling and drilling also can be done by making small modifications in the base plate by adding angle plate.  Holes can be drilled at angles of 80° 70° 60°  Rectangular surfaces can be milled at an angle of 10° 20° 30°

4.6 CONCLUSION  The Project SELF CENTERING VICE is used for drilling and milling.  This project can be useful in demonstrations in educational institutions.  It can also be used in small scale industries.  With some slight modifications and inclusion of certain tool changing mechanism our project can be further developed and analysed.  It can also be used in shaping, slotting and planar machines.

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4.7 REFERENCES 1. Design data book – P.S.G Data book. 2. Machine tool design handbook – Central machine tool Institute, 3. Strength of Materials – R.S. Khurmi 4. Manufacturing Technology – S.GOWRI 5. http://www.translatorscafe.com/. 6. http://mci-oman.com/telecommunication_main_material_spec.htm Bangalore. 7. http://www.customparnet.com/calculator/v-bending-force.

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