International Journal of Research and Innovation (IJRI)
International Journal of Research and Innovation (IJRI) 1401-1402
SIMULATION OF DEEP DRAWING DIE FOR OPTIMIZED DIE RADIUS USING FEM TECHNIQUE
G.Bhargav*, K.Durga 1.Research Scholar, Department of Mechanical Engineering,Vikas college of Engineering and Technology,Nunna, Vijayawada rural, Krishna (DIST),Andhrapradesh,India. 2.Assistant Professor, Department of Mechanical Engineering, Vikas college of Engineering and Technology,Nunna, Vijayawada rural, Krishna (DIST),Andhrapradesh,India.
Abstract Deep drawing process is one of the most used Metal Forming Process within the industrial field. Different analytical, numerical, empirical and experimental methods have been developed in order to analyze it. This work reports on the initial stages of finite element analysis (FEA) of a Deep drawing process. The objective of this study is to determine theinfluencingof die radius in drawing process and analyzing the process by varying the Die radius and keeping the Friction, and Blank Thickness as constant. In this paper Punch and blank thicknessissame;die with various geometries (with various corner radius) were drawn by using PRO/Engineer software. And an effort is made to study the simulation effect of main process variant namely die radius using finite element analysis. • Initially literature survey will be done to describe about deep drawing process and effect of die radius in press tools. • FEA models will be generated using PRO/Engineer. • Structuralanalysis will be carried out to determine the structural characteristics with the change of corner radius. • Structural analysis will be carried to find the actual effect of radius in process and also to find limiting radius value for the same. • Transient analysis will be carried to find the actual effect of radius in process and also to find limiting radius value for the same with the variation of time period. *Corresponding Author: G.Bhargav , Research Scholar, Department of Mechanical Engineering,Vikas college of Engineering and Technology,Nunna, Vijayawada rural, Krishna (DIST),Andhrapradesh,India. Published: December 16, 2014 Review Type: peer reviewed Volume: I, Issue : IV
Citation: G.Bhargav Research Scholar, (2014) SIMULATION OF DEEP DRAWING DIE FOR OPTIMIZED DIE RADIUS USING FEM TECHNIQUE
Introduction To Sheet Metal Method of Analysis In general, the complexity of these processes and the great number of factors involved in them making very difficult to select the parameter values properly. Then, different analytical, numerical and experimental methods are being developed in order to analyze the best combination of them. Now-a-days analytical methods still continue being studied and developed in spite of numerical methods allow ob-
taining solutions with high precision and detail evels in the analysis of this type of process. Finite element method has been used as well in several studies about metal forming processes recently. The main objective of this paper presented in it is the multi stage deep drawing analysis. According to John Monaghon et al, as the die radius is reduced, this increases the amount of force required to draw the material. The increased force on the punch and the greater difficulty in getting the material around the die radius causes stretching marks on the cup wall and an uneven thickness distribution. To verify the above experimental results and to validate the simulation done, several simulations were performed by varying the die radius. Furthermore, the effect of the above process parameters on the formability and quality issues are studied. The stamping of thin metallic sheets is a widely used industrial material forming process. It allows production of thin walled parts with complicated shapes such as automotive panels or structural parts. The process consists of the plastic deformation of an initial at blank subjected to the action of a rigid punch and die while constrained on the periphery by a blank holder.
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International Journal of Research and Innovation (IJRI)
The main variables involved in this type of process are: • Die Radius • Friction • Punch Radius • Blank Thickness. These factors determine the maximum punch load in drawing, the sheet-thickness variation after drawing, and the maximum limit drawing ratio. If the height ofthe work piece in industrial production is too high, multi-redrawing is necessary in order to obtain a successful product. The finite element method has recently been sufficiently developed for the analysis of metal forming processes. Hence, much research has been performed using the finite element method. The purpose of this study is to clarify the mechanics of ductile fracture in bulk metal forming processes. The following four kinds of ductile fracture criteria, that is to say, freudenthal’s fracture criterion, Cockcroft and latham’s fracture criterion, Brozzo et al.’s fracture criterion and oyane’s fracture criterion are used. These four kinds of ductile fracture criteria are used in the analysis of deep drawing. The analytical results of the work using Cockcroft and latham’s fracture criterion and using Brozzo et al.’s fracture criterion agree satisfactorily with the experimental result. Sheet metal Sheet metal is metal formed by an industrial process into thin, flat pieces. It is one of the fundamental forms used in metalworking and it can be cut and bent into a variety of shapes. Countless everyday objects are constructed with sheet metal. Thicknesses can vary significantly; extremely thin thicknesses are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate. Sheet metal is available in flat pieces or coiled strips. The coils are formed by running a continuous sheet of metal through a roll slitter. The thickness of sheet metal is commonly specified by a traditional, non-linear measure known as its gauge. The larger the gauge number, the thinner the metal. Commonly used steel sheet metal ranges from 30 gauge to about 8 gauge. Gauge differs between ferrous (iron based) metals and nonferrous metals such as aluminum or copper; copper thickness, for example are measured in ounces (and represent the thickness of 1 ounce of copper rolled out to an area of 1 square foot). There are many different metals that can be made into sheet metal, such as aluminum, brass, copper, steel, tin, nickel and titanium. For decorative uses, important sheet metals include silver, gold, and platinum (platinum sheet metal is also utilized as a catalyst.) Sheet metal is used for car bodies, airplane wings, medical tables, roofs for buildings (architecture) and many other applications. Sheet metal of iron
and other materials with high magnetic permeability, also known as laminated steel cores, has applications in transformers and electric machines. Historically, an important use of sheet metal was in plate armor worn by cavalry, and sheet metal continues to have many decorative uses, including in horse. Sheet metal workers are also known as "tin bashers" (or "tin knockers"), a name derived from the hammering of panel seams when installing tin roofs. Material used for sheet metal process Stainless steel Usage of steel as a building material is popular as a cost effective, quality material as compared to the alternatives. The three most common stainless steel grades available in sheet metal are 304, 316, and 410. Grade 304 is the most common of the three grades. It offers good corrosion resistance while maintaining formability and weldability. Available finishes are #2B, #3, and #4. Grade 303 is not available in sheet form Grade 316 possesses more corrosion resistance and strength at elevated temperatures than 304. It is commonly used for pumps, valves, chemical equipment, and marine applications. Available finishes are #2B, #3, and #4 Grade 410 is a heat treatable stainless steel, but it has a lower corrosion resistance than the other grades. It is commonly used in cutlery. The only available finish is dull. Aluminium Aluminium is also a popular metal used in sheet metal due to its flexibility, wide range of options, cost effectiveness, and other properties.[4] The four most common aluminium grades available as sheet metal are 1100-H14, 3003-H14, 5052-H32, and 6061-T6. Grade 1100-H14 is commercially pure aluminium, highly chemical and weather resistant. It is ductile enough for deep drawing and weldable, but has low strength. It is commonly used in chemical processing equipment, light reflectors, and jewelry. Grade 3003-H14 is stronger than 1100, while maintaining the same formability and low cost. It is corrosion resistant and weldable. It is often used in stampings, spun and drawn parts, boxes, cabinets, tanks, and fan blades Grade 5052-H32 is much stronger than 3003 while still maintaining good formability. It maintains high corrosion resistance and weldability. Common applications include electronic chassis, tanks, and pressure vessels Grade 6061-T6 is a common heat-treated structural aluminium alloy. It is weldable, corrosion resistant, and stronger than 5052, but not as formable. It los61
International Journal of Research and Innovation (IJRI)
es some of its strength when welded.[3] It is used in modern aircraft structures. Part Modeling In Pro/Engineer
Guide pillars are used to guide the core to assemble in desired location in process. The above image is showing final part of cavity
The above image is showing final part of core
A) Top booster is placed on cavity plate to prevent direct interaction with power press hammer B)Counter head and hole is used to assemble the top booster to the core.
Above Figure A) Cavity hole which creates outer impression of component. B) Chamfer is used to reduce the errors of guide pillar relocation. C) Guide holes are used to place the guide pillar in running process. D)Guide slots are used to place the clamps for fixing.
Above Figure
A) Corner radius is preferred for punching and drawing to prevent damage to the sheet it effects operation speed and quality. B)Core (or) male part is used to make inner impression on object and dia is depends on the same. C)Core supporting plate is connected with top booster it includes core part.
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International Journal of Research and Innovation (IJRI)
Draw tool calculations
Analysis of cup drawing:
Input: punch height Punch diameter Thickness Cup diameter
= = = =
100mm 20mm 1mm 22mm
Calculations of blank diameter:
Cup to be drawn Diameter = 91.65 Height = 100mm DO =√(dn2+ 4 dn hn) = √(91.652+4×91.65×100) = 212.27mm Calculations of drawing ratio: 4 stages of deep drawing is preferred for 100 (or) below height’s 1st draw -3.818 to 3 2nddraw - 3 to 2 3rddraw - 2 to 1 4thdraw -1 to 0 Results
1.In case of cup → the blank is circular 2.Area of blank is (D0²п)/4 = (d0²п)/4 + d1пh
No .of operations
Height in mm
Diameter in mm
Drawing ratio
0 blank
____ _____
91.65
____ _____
1st draw
25
74.7365
0.95
2nddraw
50
57.824
1.9
3rddraw
75
40.91
2.86
4thdraw
100
24
3.818
Do =√(d12+ 4d1h)
Equivalent strain
Do = √(202+ 4×20×100) = 91.65mm
Strain in the direction of 3 axis φ= φ2=91.65 ;φ2 = φw = 91.65 ; φ3= φth = 1
Blank piece diameter = 91.65mm Limiting Drawing Ratio(LDR): B = (Do/dn)
Equivalent strain:
Bi= (d¡)/(d¡+1) B = 91.65/22= 4.615
φe = √2 / 3√((φ1-φ2)²+(φ2-φ3)²+(φ1-φ3)²) = √2 / 3 √((91.65-91.65)²+(91.65-1)²+(91.65-1)²) =√2 / 3 √((0)+(90.65)²+(90.65)²) = 0.47 √(8217.4+8217.4) = 0.47 √16434.8 = 60.253
First drawing B1= 3.9 to 3.0
Introduction To Ansys
Redraw Bi = 3.0 to 1.0 (for copper, aluminum and mild steel)
ANSYS is general-purpose finite element analysis (FEA) software package. Finite Element Analysis is a numerical method of deconstructing a complex system into very small pieces (of user-designated size) called elements. The software implements equations that govern the behaviour of these elements and solves them all; creating a comprehensive explanation of how the system acts as a whole. These results then can be presented in tabulated, or graphical forms. This type of analysis is typically used for the design and optimization of a system far too complex to analyze by hand. Systems that may fit into this category are too complex due to their geometry, scale, or governing equations.
DO = diameter of blank dn= smallest diameter (cup diameter) Draw ratio in general:
Draw force: Fd max = n× π ×d ×t ×UTS d = Diameter of cup t = thickness UTS = Ultimate Tensile Strength n = Drawing coefficient (0.7 to 0.95) Fd max=0.7× 3.14×22 ×1×162 = 7833.672 MPa
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International Journal of Research and Innovation (IJRI)
Boundary conditions:
Solution
Constrained at thickness direction for cup analysis. Constrained cavity area for die analysis. Force= 7833.672 MPa
Solution – Solve – Current LS – ok
Structural Analysis Of Draw Tool With 4 Raidus (Stainless Steel Sheet)
General Post Processor – Plot Results – Contour Plot - Nodal Solution – DOF Solution – Displacement Vector Sum
The above image is the imported model of draw tool. Modeling was done in Pro-E and imported with the help of IGES (Initial Graphical Exchanging Specification). Meshed Model
The above image shows the meshed modal. Default solid Brick element was used to mesh the components. The shown mesh method was called Tetra Hydra Mesh. Meshing is used to deconstruct complex problem into number of small problems based on finite element method
The above image shows the loads applied
Post Processor
The above image shows displacement value 0.00726 mm
The above image shows von-misses stress value 12.365 N/mm2 Structural Analysis Of Draw Tool Die With 4 Raidus (Stainless Steel And Tool Steel)
The above image is the imported model of draw tool die with 4mm radius. Modeling was done in Pro-E and imported with the help of IGES (Initial Graphical Exchanging Specification). 64
International Journal of Research and Innovation (IJRI)
Meshed Model
The above image showing the meshed modal. Default solid Brick element was used to mesh the components. The shown mesh method was called Tetra Hydra Mesh.
Transient Analysis Of Draw Tool Die With 4 Radius (Stainless Steel And Tool Steel)
The above image shows displacement value 0.305595 mm General Post Processor – Plot Results – Contour Plot – Nodal Solution – Stress – Von Mises Stress
Meshing is used to deconstruct complex problem into number of small problems based on finite element method Post Processor General Post Processor – Plot Results – Contour Plot - Nodal Solution – DOF Solution – Displacement Vector Sum The above image shows von-misses stress value 2114.09 N/mm2
The above image shows displacement value 4.29347 mm General Post Processor – Plot Results – Contour Plot – Nodal Solution – Stress – Von Mises Stress
The above image shows displacement value 0.305595 mm
The above image shows von-misses stress value 7258.09 N/mm2
The above image shows von-misses stress value 2114.09 N/mm2
General Post Processor – Plot Results – Contour Plot – Nodal Solution – Stress – Von Mises Stress
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International Journal of Research and Innovation (IJRI)
Graphs For Part
The above image shows strain value 0.025091
The above image shows von-misses stress graph
For die part
Results Table Cup 4 radius
5 radius
6 radius
7raidus
8 radius
Displacement In mm
0.00072
0.00095
0.00073
0.00153
0.00190
Stress In N/ mm2
12.365
16.1762
7.57467
19.7477
34.3424
Draw tool die 4 radius
5 radius
6 radius
7raidus
8 radius
Displacement In mm
4.29347
8.065
10.7043
19.3959
16.7185
Stress In N/ mm2
7258.09
7841.36
8515.06
11323.8
9811.01
Draw tool die transient 4 radius
5 radius
6 radius
7raidus
8 radius
Displacement In mm
.3
.91
1.48
1.34
1.72
Stress In N/ mm2
2114
3076
3814
4326
3954
Strain
.025
.017
.025
.028
.022
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International Journal of Research and Innovation (IJRI)
For die transient analysis
As per the analytical results this work concludes as below. 1) Corner radius mainly effects on process speed and required force. 2) Increment of corner radius up to certain limit improves production rate quality. 3) As per the cup and die analysis results 7 radius is the better option. 4) 8 radius die performance is comparatively low than 7 radiuses die. 5) 7 radius die is providing maximum force on sheet to become sheet into desired cup shape. References 1) KopanathiGowtham, K.V.N.S. Srikanth & K.L.N. Murty 2) Yuung-ming HUANG, Shiao-cheng LU 3) R.UDAY KUMAR 4) G. Venkateswarlu, M. J. Davidson and G. R. N. Tagore 5) Y. N. Dhulugade1, P. N. Gore2 Authour
G.Bhargav* Research Scholar, Department of Mechanical Engineering,Vikas college of Engineering and Technology,Nunna, Vijayawada rural, Krishna (DIST),Andhrapradesh,India.
Conclusion The objective of this project work is to present effect of radius in deep drawing process and to suggest the optimum value of radius, for presenting the required values following process is done using FEM technique. • Literature survey and data collection is done to understand the deep drawing process, requirement’s and effects of radius. • General models and FEA models are prepared for further study. • Structural analysis is carried out on component and die structure by varying the corner radius values of 4,5,6,7 and 8 • Transient analysis is carried out to determine the values of punch deformation and stress, also to determine stresses developing on sheet. • Graphs are created for better understanding of results.
K.Durga Assistant Professor, Department of Mechanical Engineering, Vikas college of Engineering and Technology,Nunna, Vijayawada rural, Krishna (DIST),Andhrapradesh,India.
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