International Journal of Research and Innovation (IJRI)
International Journal of Research and Innovation (IJRI) OPTIMIZED DIE STRUCTURE DESIGN OF PLASTIC INJECTION MOULD USING FEM TECHNIQUE
Review Article- 1401-1402
Choppara. Yasudas, D.Gopichand Mother Theresa Institute of Technology(mist) Sanketika Nagar Sathupally Khammam,India
Abstract A die is a specialized tool used in manufacturing industries to cut or shape material mostly using a press. Like molds, dies are generally customized to the item they are used to create. Products made with dies range from simple paper clips to complex pieces used in advanced technology. The Aim of this thesis work is to reduce weight and cost of the injection mold by removing unwanted materials and using low cost materials at non-stress region areas. A general large size model will be prepared to design the mold structure using theoretical method. Complete level of mold parts and assembly will be prepared to conduct analysis. Structural analysis will be conducted on mould to find stress locations and non-effective locations. Modifications will be done on mold according to obtained results. Analysis will be carried out on modified mold for evaluation and various materials will be applied in ANSYS at nonstress effected areas to reduce the cost. Conclusion will be made from the obtained results along with comparison table’s / charts. Problem Description for Cooler Tank Die and Methodology Mound tool is the major segment in plastic component manufacturing. The product cost and quality component by depends on the mould structure cost and cooling quality only. Chinese are manufacturing plastic components at very low cost by using low cost mould. In our country we can do the same by reducing mould structure cost and, also quality of the product can be increased by providing sufficient cooling effect. The following process will guide to rectify the problems: • Evaluating existing structures. • Reducing unwanted materials by analyzing at clamping force conditions. • Evaluating and optimizing cooling channel system to provide optimum cooling effect. • By reducing the unwanted materials cost be reduced. • By optimizing cooling channel system, quality will increased by doing reduction of plastic war pages and increasing the surface quality of the product.
*Corresponding Author:
Choppara. Yasudas, Mother Theresa Institute of Technology(mist) Sanketika Nagar Sathupally Khammam,India
Published: Sep 22, 2014 Volume No: I Issue No. : III Citation:Choppara. Yasudas, D.Gopichand (2014) Optimized Die Structure Design of Plastic Injection Mould Using Fem Technique
Introduction Air coolers also called evaporative coolers are used for cooling purposes. They are different from air conditioners in the sense air conditioners use refrigeration cycle principle whereas air coolers use the evaporation of water principle. There are five main evaporative cooler parts, with each of these being composed of other parts or pieces.The first part is the Blower which creates the airflow into and out of the cooler.Then there are the pads which filter and cool the air. These pads are attached to the side grill; this grill is supported with side grill pillars and 1
International Journal of Research and Innovation (IJRI)
a mounting stand for motor. And the final part is bottom tank used to store water.
the circulating water will eventually be used up. So tank acts as a water reservoir in order to keep the pads damp if the pads ever dry out, the cooler will not be able to cool the air. We have taken up the parameters of an already prepared air cooler and prepared a model for air cooler tank. And that mould tool design is done based on the model, by using CREO 2.0(PRO/ENGINEER) software. After determining the values of the mould tools, manufacturing drawings are prepared with full details selecting the appropriate materials. Subsequently, these mould tools are manufactured as per drawing prepared and subjected to quality control tests. Introduction TO CAD
Figure 1 Air cooler First, when the evaporative cooler is on, the pump circulates water from the tank of the cooler to the top. It filters down into the pads where some of it is absorbed, but what isn’t absorbed is passed down to the tank of the machine again where it will repeat the cycle of being circulated again to the top. Some of the water will be evaporated from the pads and
Computer Aided Design (CAD) is a technique in which man and machine are blended in to problem solving team, intimately coupling the best characteristics of each. The result of this combination works better than either man or machine would work alone , and by using a multi discipline approach, it offers the advantages of integrated team work.
MODEL OF AIR COOLER TANK
The above image shows sketch view
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International Journal of Research and Innovation (IJRI)
The above image shows Model rare view
The above image shows Final model of cooler tank 2D DRAWINGS OF COOLER TANK
The above image shows 2d drafting views along with dimensions of cooler tank 3
International Journal of Research and Innovation (IJRI)
MOULD EXTRACTION A die is usually made in two halves and when closed it forms a cavity similar to the casting desired. One half of the die that remains stationary is known as cover die and the other movable half is called “ejector die�. The die casting method is used for castings of nonferrous metals of comparatively Low fusion temperature. This process is cheaper and quicker than
permanent or sand mould casting. Most of the automobile parts like fuel pump, carburetor bodies, Horn heater, wipers, brackets, steering wheels, hubs and crank cases are made with this process. Core: The core which is the male portion of the mold forms the internal shape of the molding. Cavity:The cavity which is the female portion of the mold, gives the molding its external form.
CAVITY
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The above image shows cavity
CORE
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International Journal of Research and Innovation (IJRI)
The above image shows core DIE DESIGN Cavity Back Plates- Plates used as a support for the mold cavity block, core block.
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International Journal of Research and Innovation (IJRI)
Ejector Plate – Ejector plate is used for pushing ejector pins, retainer plate etc
Ejector Pins - Pins that are pushed into a mold cavity from the rear as the mold opens to force the finished part out of the mold. The above image is showing ejector plate and ejector pins
The above image is showing ejector pin
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International Journal of Research and Innovation (IJRI)
Retainer Plate - The plate on which demountable pieces, such as mold cavities, ejector pins, retainer pins are mounted during molding.
Retainer Pins – Retainer pins are used to push the retainer plate
The above image is showing retainer pin
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International Journal of Research and Innovation (IJRI)
Guide Pillar
Guide Bush
The above image is showing guide bush and guide pillar Guide Sleeves
2D drawings
The above image is showing guide bush and guide pillar
The above image is showing cavity back plate and retaining plate 9
International Journal of Research and Innovation (IJRI)
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International Journal of Research and Innovation (IJRI)
DIE ASSEMBLY
The above image is showing die assembly
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International Journal of Research and Innovation (IJRI)
INTRODUCTION TO ANSYS 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. ANSYS is the standard FEA teaching tool within the Mechanical Engineering Department at many colleges. ANSYS is also used in Civil and Electrical Engineering, as well as the Physics and Chemistry departments. MATERIAL PROPERTIES AND BOUNDARY CONDITIONS MATERIAL: EN 38 Material Properties: Youngs Modulus (EX) : 20900N/mm2 Poissons Ratio (PRXY) : 0.27 Density :0.000007876kg/mm3 Hardness, Brinell 179 - 235 Hardness, Knoop 229 Hardness, Rockwell B 93 Hardness, Rockwell C 15 Hardness, Vickers 217 Bulk Modulus 140 GPa 20300 ksi Typical for steel Machinability 55 % Shear Modulus 80.0 GPa Carbon, C 0.32 - 0.38 % Iron, Fe 97.15 - 98.08 % Manganese, Mn 1.45 - 2.05 % Phosphorous, P <= 0.035 % Silicon, Si 0.15 - 0.35 % Sulfur, S <= 0.040 %
Reduction of Area 40 % Modulus of Elasticity 205 GPa Bulk Modulus 140 GPa Poissons Ratio 0.29 Machinability 70 % Shear Modulus 80.0 GPa Thermal Properties Metric Specific Heat Capacity 0.486 J/g-째C Thermal Conductivity 51.9 W/m-K Component Elements Properties Metric Carbon, C 0.14 - 0.20 % Iron, Fe 98.81 - 99.26 % Manganese, Mn 0.60 - 0.90 % Phosphorous, P <= 0.040 % Sulfur, S <= 0.050 % c22 material properties Density 8.22 g/cc Tensile Strength, Ultimate 765 MPa Tensile Strength, Yield 380 MPa@Strain 0.200 % Modulus of Elasticity 139 GPa Boron, B <= 0.0080 % Carbon, C 0.10 % Chromium, Cr 22 % Cobalt, Co 1.5 % Iron, Fe 18 % Manganese, Mn <= 1.0 % Molybdenum, Mo 9.0 % Nickel, Ni 47 % Silicon, Si <= 1.0 % Tungsten, W 0.60 % OHNS Oil Hardened Non-shrinking Steel Density 7.83 g/cc Modulus of Elasticity214 GPa Component Elements Properties Carbon, C 0.94 % Chromium, Cr 0.50 % Iron, Fe 96.56 % Manganese, Mn 1.2 % Silicon, Si 0.30 % Tungsten, W 0.50 %
Metric
CONSTRAINED AT BOTTOM FORCE ON TOP 741.255 TONS
MILD STEEL (MS) Physical Properties Metric Density 7.87 g/cc Mechanical Properties Metric Hardness, Brinell 126 Hardness, Knoop 145 Hardness, Rockwell B Hardness, Vickers 131 Tensile Strength, Ultimate 440 MPa Tensile Strength, Yield 370 MPa Elongation at Break 15 % 15 % 12
International Journal of Research and Innovation (IJRI)
STRUCTURAL ANALYSIS OF STANDARD MOULD
The above image is the imported model of composite shaft. Modeling was done in Pro-E and imported with the help of IGES (Initial Graphical Exchanging Specification). 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. Meshing is used to deconstruct complex problem into number of small problems based on finite element method.
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International Journal of Research and Innovation (IJRI)
The above image is showing the loads applied on a mold
The above image shows the displacement, value is 0.007979mm
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International Journal of Research and Innovation (IJRI)
The above image shows the stress, value is 5.61561N/mm2 Structural Analysis of Reduced Thickness
The above image shows the displacement, value is 0.008118mm
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International Journal of Research and Innovation (IJRI)
The above image shows the stress, value is 5.6919N/mm2
Structural Analysis of Reduced Thickness Two
The above image shows the displacement, value is 0.008713mm
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International Journal of Research and Innovation (IJRI)
The above image shows the stress, value is 10.5942N/mm2 Thermal Analysis For Standard Mould
The above image is the imported model of composite shaft. Modeling was done in Pro-E and imported with the help of IGES (Initial Graphical Exchanging Specification).
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International Journal of Research and Innovation (IJRI)
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. Meshing is used to deconstruct complex problem into number of small problems based on finite element method.
The above image shows the melted material temperature
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International Journal of Research and Innovation (IJRI)
The above image shows the cooling channel temperature
The above images shows the contact area with air
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Results
The above image shows the nodal temperature
The above image shows the thermal gradient
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International Journal of Research and Innovation (IJRI)
The above image shows the Thermal flux
Thermal Analysis For Modified Cooling Channel
Nodal temperature
The above image shows the nodal temperature
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International Journal of Research and Innovation (IJRI)
The above image shows the thermal gradient
The above image shows the Thermal flux
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International Journal of Research and Innovation (IJRI)
MANUFACTURING PROCESS
chanical properties without changing the product shape.
By designed the mould tool for air cooler tank, with the parameters now we can manufacture the air cooler tank according to the dimensions. The flow chart of the manufacturing process of the air cooler tank is given below. Raw material Hot die steels are most commonly used mould tool materials. they have Excellent toughness, ductility and harden ability .Used for vary large dies especially in thickness greater than 200mm .Also used for hot and warm forging and in extrusion tooling such as intricate dies and also dummy block ,liners, etc. Surface grinding After selecting raw material surface grinding is done, Surface Grinding is a widely used process of machining in which a spinning wheel covered in rough particles cuts chips of metallic or non metallic substance making them flat or smooth. Heat treatment To increase the strength of the material it is heat treated. Heat treatment is an important operation in the manufacturing process of machine parts and tools. Heat Treatment is the controlled heating and cooling of metals to alter their physical and me-
Heat Treatment is often associated with increasing the strength of material, but it can also be used to alter certain manufacturability objectives such as improve machining, improve formability, restore ductility after a cold working operation. Thus it is a very enabling manufacturing process that can not only help other manufacturing process, but can also improve product performance by increasing strength or other desirable characteristics. CNC machining In modern CNC systems, end-to-end component design is highly automated using CAD/CAM programs. The programs produce a computer file that is interpreted to extract the commands needed to operate a particular machine, and then loaded into the CNC machines for production. Since any particular component might require the use of a number of different tools - drills, saws, etc. - modern machines often combine multiple tools into a single "cell". In other cases, a number of different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case the complex series of steps needed to produce any part is highly automated and produces a part that closely matches the original CAD design. After undergoing CNC machining process the mold tool i.e. core and cavity are shown in following figures.
Cavity
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Core
Air cooler tank
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International Journal of Research and Innovation (IJRI)
MANUFACTURING PROCESS CUTTING TOOL
CORE ROUGHING
PLAY PATH
VERICUT
ROUGHING PROGRAM %G71 O0001 N0010T1M06 S5000M03 G00X10.Y-10. G43Z0.H01 25
International Journal of Research and Innovation (IJRI)
CAVITY ROUGHING
ROUGHING PROGRAM G71 O0001 N0010T1M06 S5000M03 G00X111.616Y-139.396 G43Z0.H01 G01X111.854Y-140.92Z-1.753F200. X112.545Y-142.3Z-2.34 X113.625Y-143.402Z-2.684 X114.989Y-144.124Z-2.874 X116.508Y-144.395Z-2.94 X116.616Y-144.396 G03X116.616Y-144.396I0.J5. G02X120.025Y-146.076I0.J-4.3 G01X120.153Y-146.242 G03X123.68Y-146.474I1.865J1.433 X116.616Y-149.396I-7.064J7.078 G02X120.228Y-151.363I0.J-4.3 G01X120.353Y-151.557 G03X123.997Y-152.454I2.298J1.484 X116.616Y-154.396I-7.381J13.058 G02X120.313Y-156.501I0.J-4.3
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International Journal of Research and Innovation (IJRI)
Structural analysis
Standard mold Reduced thickness Reduced thickness two
Displacement in mm 0.007979 0.008118 0.008713
Stress In N/mm2 5.61561 5.6919 10.5942
Thermal analysis
Thermal gradient Standard mold 240.348 Modified cooling 260.207 CONCLUSION •
• • • • • •
•
In this project, designed an air cooler water tank as per the parameters; tank capacity is 15 liters, width 380mm, length 420mm, and height 260mm. Core and Cavity is extracted for the tank. Die design is prepared for the same. The modeling, core-cavity extraction and die design is done in creo 2.0. CNC program is generated for core and cavity to conducting milling operation. Static and thermal analysis is conducted on mould structure for weight reduction and for optimized cooling channels. As per the analytical results reduction of spacer housing thickness and reduction of core back support is also performing well, so better to use reduced thick 2 model for cast and weight reduction. Optimized location is the better option for thermal behavior because of high flux and gradient rates.
Thermal flux 12.4981 13.5308
Nodal temperature 513 513
Authors
Choppara. Yasudas 20 Year’s Teching Experience In Govt Polytechnic College
BIBLIOGRAPHY 1) Machine design, T.V.Sundararajamoorthy 2) Machine design, R.S.Khurmi/J.K.Guptha (S.CHAND) 3) Design data book:P.S.G.College of Technology (Kalaikathirachchagam), 4) Www. google.com “online” 5) Design of machine element:V.B.Bandari (TATA McGraw-hill 6) Injectionmould design: R.G.W. PYE (East-West press Pvt. Ltd
D.Gopichand Qualification: m.tech Designation: assistant profressor Experience :4 yr in teaching & 2 yr experience in InfoTech as design engineer
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