study of cutting tools & jig fixture
DESCRIPTION
Anuj kumarTRANSCRIPT
VIVEKANAND INSTITUTE OF TECHNOLGY AND
SCIENCE(gzb)
STUDY OF CUTTING TOOLS & JIGS FIXTURE
A Project onStudy of Cutting Tools and Jigs Fixture
Submitted for partial fulfillment of award of BACHELOR OF TECHNOLOGY Degree
InMECHANICAL ENGINEERING
By ANUJ KUMAR ALOK SHARMA DEVVRAT SINGH S.M ARSHIL ZAIDI VIVEKANAND INSTITUTE OF TECHNOLOGY AND
SCIENCE,GHAZIABAD UTTAR PRADESH TECHNICAL UNIVERSITY,LUCKNOW
CANDIDATES DECLARATION
We hereby the declare the work being presented in this report entitled ” STUDY OF CUTTING TOOLS AND JIG FIXTURE” is an authentic record of our own work carried out under the supervision of
Mr. “SUBHANKAR KARMAKAR” The matter embodies in this report has not been
submitted by us for the award of any other degree. Name of students ANUJ KUMAR ALOK SHARMA DEVVRAT SINGH S.M ARSHILZAIDI
CONTENTS
1. INTRODUCTION2. TOOL DESIGN METHOD3. DESIRABLE PROPERTIES OF TOOLING MATERIAL4. TOOLING MATERIAL AND HEAT TREATMENT5. SELECTION OF TOOLING MATERIAL6. TOOL GEOMETRY7. CHIPS FORMATION8. TYPE OF CHIPS9. TOOL FAILURE AND TOOL CUTTING LIFE10. EFFECT OF DIFFERENT PARAMETERS ON TOOL
LIFE11. IMPORTANCE OF JIG FIXTURE12. MANUFACTURING OF HAND VICE13. CONCLUSION
1.INTRODUCTION
This project deals with “STUDY OF CUTTING TOOLS AND JIGS FIXTURE” with an aim of increasing the tool life. Various factors play an important role in deciding the tool life such as Geometry of tools, tool material, machining operations, types of coolant used and cutting environment etc.
This project describes the tool design procedures, various tool
materials, selection of appropriate tool for machining operations and explains the reasons for tool failure. It also describes the factors for increasing the tool life.
This project also completely explains the various types of “JIGS
AND FIXTURES” how they are manufactured, principle of location, their specifications & their importance.
The project also includes manufacturing of “HAND VICE”.
2.TOOL DESIGN METHOD
1.Statement of the problem Why the tool is needed? What are the required capabilities of
the tool The type of machine the tool must
be used on The number of the part to be
produced Other pertinent information
concerning the part.
2.TOOL DESIGN METHOD
2.The need analysis Will the tool used by the skilled or
unskilled operators? How many parts can be held on the tool? What are the hole-location tolerances on
the part? What provisions are to be made for
coolant Is the cutting force heavy or light? Etc.
2.TOOL DESIGN METHOD
3.Research and the ideation(sketches)
Dimension of the part to be held or produced
Kind of the material from which the part is made
The tolerance of the part Dimensions of the machine Limitations of the machine Amount of the tonnage to blank the
part.
2.TOOL DESIGN METHOD
4. Tentative design solutions
5.The Finished Design
3.DESIRABLE PROPERTIES OF TOOLING MATERIAL
Strength:Plasticity:Elasticity and stiffness:Elastic limit: Toughness:Hardness:Machinability:Endurance limit:Cost:
4.TOOLING MATERIALS
High carbon steel High speed steel(HSS) Coated high speed steel Cast alloy Cemented carbides Non-Tungsten Cemented Carbides Ceramics (Cemented oxides) Kyon Sialon(Si-Al-O-N) Boron Nitride Diamond Polycrystalline Diamond (PCD) and Solid Film
Diamond (SFD)
4.HEAT TREATMENT
Normalizing: Annealing: Spheroidizing: Hardenability: Stress relieving: Stabilizing: Hardening: Pack hardening: Quenching: Tempering: Double tempering: Decarburization:
5.SELECTION OF TOOLING MATERIAL
Single carbide steel-Machining grey cast iron,brass bronze etc
Composite carbide -Machining Steel
5.SELECTION OF TOOLING MATERIAL
Cemented Carbide
5.SELECTION OF TOOLING MATERIAL
Cemented carbide
6.TOOL GEOMETRY
6.TOOL GEOMETRY
6.TOOL GEOMETRY
6.TOOL GEOMETRY
MILLING CUTTER
7.Chip Formation
All machining processes involve formation of chips by deforming the work material on the surface of the job with the help of the cutting tool.
7.Chip Formation
8.TYPE of CHIPS
(a) tightly curled chip; (b) chip hits workpiece and breaks; (c)continuous chip moving away from workpiece; and (d) chip hits tool shank and breaks off.
8.TYPE of CHIPS
Continuous chips
During the cutting of ductile materials like low carbon steel, copper, brass etc., a continuous ribbon type chip is produced. The pressure of the tool makes the material ahead of the cutting edge deform plastically.
8.TYPE of CHIPS
Continuous chips with built up edge
Continuous chips with built up edge
The temperature is high at the interface between the chip and the tool during the cutting. Also, the work material slides under heavy pressure on the rake face before being transformed into a free chip. In these conditions, some portion of the chip may stick to the rake face of the tool. Because of such a close contact, it discharges its heat to the tool and attracts more of the deforming work material and thus the size of “built up edge” goes on increasing and breaks up after a critical stage.
8.TYPE of CHIPS
Discontinuous chips
These chips are produced during the cutting of brittle material like cast iron, and brasses. Even a slight plastic deformation produced by a small advance of the cutting edge into the job leads to a crack formation in the deforming zone.
9. TOOL FAILURE MECHANISM OF TOOL WEAR1. Adhesion
2. Abrasion
9. TOOL FAILURE MECHANISM OF TOOL WEAR 3. Diffusion
4. Oxidation
9. TOOL FAILURE SOME TOOL FAILURE;1.Flank wear- VB=0.3mm; VBmax=0.6mm.2. Fracture failure.3. Temperature failure4. Gradual wear5. Crater wear- KT = 0.06 + 0.3f, where f is the feed per revolutions6. Plastic Deformation7. 2 Mechanical Breakage
9. TOOL FAILURE
9. TOOL CUTTING LIFE
Taylor’s Empirical Equation:
VT n =CWhere, T = tool life time; usually in minutesV = cutting velocity, m/minC = constant; the cutting velocity for 1 minute of elapsed time before reaching the wear limit of the tooln = constant which is considered a characteristic of the tool material, called tool life index.
Typical Tool Life Exponential Graph
9. TOOL CUTTING LIFE
Modified Taylor’s Equation
This incorporates the feed rate and depth of cut having their own index X and Y where the indexes are obtained experimentally. Typically from machining practices these values can be taken as: n=0.15, x=0.15, and y=0.6 (typical values)
VTndxfy = CThe above equation may be rewritten for determining the time as shown:
T=C1/nV-1/nD-x/nf-y/n
9.CUTTING LIFE
Optimum Cutting Speed
10.EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE
Effect of Varying Rake Angle
10. EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE
Influence of Feed Rate on T.L
10. EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE
Influence of Tool Shape on Cutting Speed and Tool Life
10. EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE
Influence of speed and feed on the economics of MRR
10. EFFECT OF DIFFERENT PARAMETERS ON TOOL LIFE
Relationship between the specific wear rate and tool temperature
11.IMPORTANCE OF JIGS & FIXTURES
To hold the Work Piece To guide the tool (jigs) Protects the tool from accidental
failure Better productivity Automates the machine tools Ensures machining accuracy Less skilled labor can be used
12.Manufacturing of Hand vice
The manufacturing of hand vice is done with an aim of practically examining all the factors involved in various machining operations, that we have studied in our project. All the factors were carefully studied with an approach to increase the tool life for e.g tool geometry, tool material, temperature, cutting fluid, and proper use of jigs & fixtures etc.
11.CONCLUSION Parameter Influence and interrelationship
Cutting speed, depth of cut , feed Rate , cutting fluids.Tool angles
Continuous chip
Built-up-edge chip
Discontinuous chip
Temperature rise.
Tool wear
Machinability
Forces power, temperature rise, tool life, type of chips, surface finish.influence on chip flow direction; resistance to tool chipping.
Good surface finish ; steady cutting forces ; undesirable in automated machinery.Poor surface finish , thin stable edge can product tool surface.Desirable for ease of chip disposal ; fluctuating cutting forces ; can affect surface finish and cause vibration and chatters.
Influences surface finish , dimensional accuracy, temperature rise, forces and power.Influences surface finish , dimensional accuracy , temperature rise , forces and power.Related to tool life , surface finish , forces and power
11. CONCLUSION
Parameter Influence and interrelationship
Selection of machining process
Selection of tool material Cutting environment
Selection of proper jigs and fixture
Accuracy of machine
Vibration in machine
Right machining process minimize the tool wear ,& gives better tool life.
Selection of tooling material is most important factor. Tool material always should have higher strength then the material to be cut.
Tool life is also depend upon the right jigs/fixture is used. They minimize the accidental tool failure & gives the direction to tool.
Accurate machine have low tool wear rate.
Vibration in machine increase the tool wear.
11. CONCLUSIONParameter Influence and interrelationship
Mechanical properties of tool material
chemical properties of tool material
Selection of cutting fluid
Proper heat treatment
Coating Material
Skill of workers
Tool life is directly depend upon the mechanical properties of tool material
Oxidation decrease the tool life
A proper cutting fluid can increase the tool life uptu 20%
A heat treated tool can with stand higher temp.& have longer tool lifeA proper Coated material can increase the tool life uptu 300%Skill worker have better knowledge of cutting process & machine operation
11. CONCLUSIONParameter Influence and interrelationship
Proper Methods of Applying Cutting Fluids
11. CONCLUSIONParameter Influence and interrelationship
Proper heat treatment
Coating Material
Skill of workers
A heat treated tool can with stand higher temp.& have longer tool lifeA proper Coated material can increase the tool life uptu 300%Skill worker have better knowledge of cutting process & machine operation
Thank you