55811_gtu project report 8th sem on rpt

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EVALUATION OF CONFORMAL COOLING CHANNEL

DESIGN IN DIRECT METAL LASER SINTERING FOR

RAPID TOOLING

A PROJECT REPORT

Submitted by

Varun C. Vyas (120120119191)

Malavya A. Shrotriya (120120119063)

Dhrumil B. Patel (120120119048)

In fulfillment for the award of the degree

Of

BACHELOR OF ENGINEERING

in

Mechanical Engineering

Gandhinagar Institute of Technology, Kalol

Gujarat Technological University, Ahmedabad

April, 2016

Gandhinagar Institute of Technology


2016

2

PLATINUM FOUNDATION MANAGED

GANDHINAGAR INSTITUTE OF

TECHNOLOGY (Affiliated to Gujarat Technological University)

Khatraj-Kalol Road, At: Moti-Bhoyan, Tal: Kalol, Dist: Gandhinagar

Website: www.git.org.in

CERTIFICATE This is to certify that the work of Industrial Defined Project entitled “Evaluation Of Conformal

Cooling Channel Design In Direct Metal Laser Sintering For Rapid Tooling” has been

carried out by Varun C. Vyas (120120119191) under my guidance in partial fulfillment for the

degree of Bachelor of Engineering in Mechanical 8th

Semester at the Department of Mechanical

Engineering, Gandhinagar Institute of Technology, Moti Bhoyan, Gandhinagar, Gujarat, during

the academic year 2015-2016 and his work is satisfactory. This student has successfully

completed all the activity under my guidance related to Industrial Defined Project for 7th

semester.

Internal Guide,

Assistant Professor,

Himanshu K. Barot

Mechanical Engineering Department.

Prof. Umang J. Patdiwala,

Head of Department,

Mechanical Engineering,


http://www.git.org.in/

3








carried out by Malavya A. Shrotriya(120120119063) under my guidance in partial fulfillment

for the degree of Bachelor of Engineering in Mechanical 8th

Semester at the Department of

Mechanical Engineering, Gandhinagar Institute of Technology, Moti Bhoyan, Gandhinagar,

Gujarat, during the academic year 2015-2016 and his work is satisfactory. This student has

successfully completed all the activity under my guidance related to Industrial Defined Project

for 7th

semester.

Internal Guide,


Himanshu K. Barot



Head of Department,




4








carried out by Dhrumil B. Patel(120120119048) under my guidance in partial fulfillment for the

degree of Bachelor of Engineering in Mechanical 8th

Semester at the Department of Mechanical

Engineering, Gandhinagar Institute of Technology, Moti Bhoyan, Gandhinagar, Gujarat, during

the academic year 2015-2016 and his work is satisfactory. This student has successfully

completed all the activity under my guidance related to Industrial Defined Project for 7th

semester.

Internal Guide,


Himanshu K. Barot



Head of Department,




5

GUJARAT TECHNOLOGICAL UNIVERSITY [UNDERTAKING ABOUT ORIGINALITY OF WORK]

We hereby certify that we are the sole authors of this IDP project report and that neither any part of this

IDP project report nor the whole of the IDP Project report has been submitted for a degree by other

student(s) to any other University or Institution.

We certify that, to the best of our knowledge, the current IDP Project report does not infringe upon

Anyone copyright nor violate any proprietary rights and that any ideas, techniques, quotations or any

other material from the work of other people included in our IDP Project report, published or otherwise,

are fully acknowledged in accordance with the standard referencing practices. Furthermore, to the extent

that we have included copyrighted material that surpasses the boundary of fair dealing within the

meaning of the Indian Copyright (Amendment) Act 2012, we certify that we have obtained a written

permission from the copyright owner(s) to include such material(s) in the current IDP Project report and

have included copies of such copyright clearances to our appendix.

We have checked the write up of the present IDP Project report using anti-plagiarism database and it is

in the allowable limit. In case of any complaints pertaining to plagiarism, we certify that we shall be

solely responsible for the same and we understand that as per norms, University can even revoke BE

degree conferred upon the student(s) submitting this IDP Project report, in case it is found to be

plagiarized.

Project Title: Evaluation Of Conformal Cooling Channel Design In Direct Metal Laser Sintering For Rapid Tooling.

College Group ID:GIT_ME_15_53

120120119191

120120119063

120120119048

Name of internal Guide:

Sign of Internal Guide:

GTU Team ID:

VARUN VYAS MALAVYA SHROTRIYA DHRUMIL PATEL Prof. Himanshu K. Barot

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Acknowledgement

We have taken efforts in this project. However, it would not have been possible without the kind

support and help of many individuals and organizations. We would like to extend my sincere

thanks to all of them.

We are highly indebted to Prof. Himanshu K. Barot for their guidance and constant supervision

as well as for providing necessary information regarding the project. We take this opportunity to

thank all my friends and colleagues who started us out on the topic and provided extremely

useful review feedback and for their all-time support and help in each and every aspect of the

course of my project preparation. We are grateful to my college Gandhinagar Institute of

Technology, Gandhinagar for providing us all required resources and good working

environment.

We would like to express our gratitude towards Head of Department Prof Umang J. Patdiwala

and Director Dr N M Bhatt for their kind co-operation and encouragement which helped us in

this project.

Varun C Vyas (120120119191)


Dhrumil B. Pate l (120120119048)

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ABSTRACT

This project shows the layer by layer manufacturing Technique, by using direct

Metal Laser Sintering. Due to globalization & competition in the market to keep

the product 1st in the market is very important. This study shows how the

conformal cooling method of Direct Metal Laser Sintering Technique helps to

reduce the cycle time and improve the productivity of the product using Rapid

Tooling compare to the conventional method, which is going now a days. So, after

implementing this method, it will not only reduce the time but also improves the

quality. This study use the analysis software model- which compare the various

parameters like temperature, time, pressure, stress etc. are evaluated. Modular

injection molding tool is constructed with the view to greatly reduce the time to

market. The first variant was made by conventional methods of machining and the

second variant was made by combination of conventional methods and

unconventional rapid prototyping technology Direct Metal Laser Sintering

(DMLS).

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TABLE OF CONTENT

NAME OF CONTENT PAGE NO.

TITLE 1

CERTIFICATE 2

DECLARATION FORM 5

ACKNOLEGMENT 6

ABSTRACT 7

LIST OF FIGURE 9

CHAPTER 1

INTRODUCION 11

DEFINATION 12

SCOPE AND OBJECTIVE OF THE WORK 13

METHODOLOGY 15

STRUCTURE OF THE WORK 16

CHAPTER 2

RAPID PROTOTYPING 18

ONE DAY CONCEPT 19

RAPID MANUFACRUTING 19

RAPID TOOLING 21

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INDUSTRIES BEING SERVED 22

INSTALLATIONS BY COUNTRY 22

CHAPTER 3

ADDITIVE MANUFACTURING

STEREO LITHOGRAPHY 23

SELECTIVE LASER SINTERING 25

3-D PRINTING 26

DIRECT METAL LASER SINTERING 27

CHAPTER 4

EXPERIMENTAL DATA 31

CONVENTIONAL INSERT MODE

CHAPTER 5

CONFORMAL COOLING INSERT MODE 33

CHAPTER 6

PRACTICAL DATA BY CONVENTIONAL METHOD 48

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CHAPTER 7

PRACTICAL DATA BY CONFORMAL COOLING 49

CHANNEL METHOD

CHAPTER 8

CONCLUSION 50

ANALYSIS OF CANVAS

5.1) AEIUO Summary

5.2) Empathy Summary

5.3) Ideation Canvas

5.4) Product Development

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Evaluation of Conformal Cooling Channel Design in Direct Metal

Laser Sintering For Rapid Tooling

A PROJECT REPORT

Submitted by

Varun C. Vyas (120120119191)


Dhrumil B. Patel (120120119048)

In fulfillment for the award of the degree

Of

BACHELOR OF ENGINEERING

In


Gandhinagar Institute of Technology, Kalol

Gujarat Technological University, Ahmedabad

APRIL 2016

12

CHAPTER 1

INTRODUCTION

Rapid prototyping belongs among modern manufacturing technologies, where the resulting

product is made by adding material layer-by-layer, unlike subtracting technologies (milling and

drilling), where the resulting product is made by removing material manufacturing technologies.

There are several rapid prototyping technologies based on the adding material, the main

differences are in a used material and product building technologies. Between this technologies

belong, for example; stereo lithography (SL), laminated object manufacturing (LOM), fused

deposition modelling (FDM), selective laser sintering (SLS) and direct metal laser sintering

(DMLS). All these technologies are based on creation of real product directly from 3D CAD data

in a few hours; this results in speeding up process planning and tooling design, because of

possibility to provide a real product at an earlier design stage. Laser sintering is one of the

leading commercial processes for rapid fabrication of functional prototypes and tools. The

process creates solid three-dimensional objects by bonding powdered materials using laser

energy.

Direct metal laser sintering (DMLS) allows creating fully functional metal part without using

any tools and without any shape restrictions. The parts produced by this technology have

mechanical properties fully comparable with cast or machined parts. Benefits of this technology

increases with shape complexity; that means the more complex part, the more economical the

process becomes. Principle of this technology is based on melting very thin layers of metal

powder. The process begins by applying first layer onto a steel platform and melting required

contour. Then is another layer applied and process continuous until the whole part is made.

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1.1 DEFINATION OF A PROBLEM:

The competition in the industries is due to globalization created accountability at time and cost.

The present manufacturing method is material removal by cutting technology which consumes

more raw materials, tooling cost, more sequences of operations and more time and cost. The

question comes how to reduce time and development cost? By using the techniques of layer by

layer manufacturing by using conformal cooling concept we can get better quality of the

product.

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1.2 SCOPE AND OBJECTIVE OF THIS WORK:

Conformal cooling with Direct Metal Laser Sintering helps achieving these

improvements and advantages:-

In terms of geometry:

Routing options for cooling channels are almost infinite. This makes it possible to create an ideal

cooling channel in a well-defined distance to the cavity. A conventional drilled cooling

mechanism cannot achieve this much practice. Cooling channel cross- sections can take any

shape (oval vs. round). Changing cross sections or forking the cooling channel can easily be

done without splitting up. This allows for additional heat/cooling advantages in areas that cannot

be reached by conventional methods.

Quality in the process of injection molding:

A more effective mold temperature control system saves time and cost in the process of injection

molding. Warping and sink marks are minimized by evenly cooling out the plastic melt.

Avoiding internal stresses helps to produce better parts with the same amount of required

material. This opens up the potential for further applications.

Process cost:

Heating/cooling at critical parts inside the tool, which cannot-or only hardly reached by

conventional methods, becomes feasible ( e.g.:- long and lean cores, areas around hot- runners or

small sliders). Using special copper heat conductors or the other complex measures becomes

obsolete. An evened out temperature level can help to improve tool life time. This becomes

relevant especially in die casting tools that are exposed to extreme temperature variations.

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METHODOLOGY:

The methodology shows how the work is carried out.

The 3-D model is generated using Solid Edge Software as per the requirement. The different

models generated are model of product, different plates, cores and molds, conventional type of

insert, conformal cooling model of insert etc.

The analysis is carried out of both- conventional and conformal cooling method using the

MOLDEX software by which we get different data like cycle time, filling time, packing time,

cooling time, shear stress, air traps, shrinkage, temperature, density etc.

The practical performance of the conventional is carried out and the practical data are collected

using conventional method. Using conventional insert glass are manufactured.

The conformal cooling insert is manufactured and by using that insert glass are manufactured

and data are collected.

By using all this data different parameters like cycle time, cooling time, surface roughness etc.

are evaluated.

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1.4 STRUCTURE OF THE WORK:

CHAPTER-1

INTRODUCTION:

This chapter contains defination of a problem, scope and objective of the project

work and methodology.

CHAPTER -2

OVERVIEW OF RPT AND RAPID TOOLING:

This chapter contains the basic information such as different methods of RPT,

Rapid Tooling DMLS Techniques and Conformal cooling.

CHAPTER-3

EXPERIMENTAL DATA:

This chapter contains the data required for to carry out the experiment like

component drawing, core drawing by using conventional method and conformal

cooling method both. Also it shows various mold plates deawing which are

required to carry out the setup.

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CHAPTER-2

RAPID PROTOTYPE AND TOOLING

The first methods for rapid prototyping became available in the late 1980s and were used to

produce models and prototype parts. Today, they are used for a wide range of applications and

are used to manufacture production-quality parts in relatively small numbers if desired without

the typical unfavourable short-run economics. This economy has encouraged online service

bureaus. Historical surveys of RP technology start with discussions of simulacra production

techniques used by 19th-century sculptors. Some modern sculptors use the progeny technology

to produce exhibitions. The ability to reproduce designs from a dataset has given rise to issues of

rights, as it is now possible to interpolate volumetric data from one-dimensional images.

As with CNC subtractive methods, the computer-aided-design - computer-aided

manufacturing CAD-CAM workflow in the traditional Rapid Prototyping process starts with the

creation of geometric data, either as a 3D solid using a CAD workstation, or 2D slices using a

scanning device. For RP this data must represent a valid geometric model; namely, one whose

boundary surfaces enclose a finite volume, contains no holes exposing the interior, and do not

fold back on themselves. In other words, the object must have an “inside.” The model is valid if

for each point in 3D space the computer can determine uniquely whether that point lies inside,

on, or outside the boundary surface of the model. CAD post-processors will approximate the

application vendors’ internal CAD geometric forms (e.g., B-splines) with a simplified

mathematical form, which in turn is expressed in a specified data format which is a common

feature in Additive Manufacturing: STL (stereo lithography) a standard for transferring solid

geometric models to SFF machines. To obtain the necessary motion control trajectories to drive

the actual SFF, Rapid Prototyping, 3D Printing or Additive Manufacturing mechanism, the

prepared geometric model is typically sliced into layers, and the slices are scanned into lines

[producing a "2D drawing" used to generate trajectory as in CNC`s tool path, mimicking in

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reverse the layer-to-layer physical building process.

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2.2 ONE DAY CONCEPT:

The high degree of automation makes additive manufacturing ideally suited when aiming for

short throughput time. Recent developments makes possible day to reduce the total throughput

time for one off parts to one day, including quotation, order placement, planning, production and

delivery.

2.3 RAPID MANUFACTURING:

Rapid Manufacturing is a new area of manufacturing developed from a family of

technologies known as Rapid Prototyping. These processes have already had the effect of both

improving products and reducing their development time; this in turn resulted in the

development of the technology of Rapid Tooling, which implemented Rapid Prototyping

techniques to improve its own processes. Rapid Manufacturing has developed as the next stage,

in which the need for tooling is eliminated. It has been shown that it is economically feasible to

use existing commercial Rapid Prototyping systems to manufacture series parts in quantities of

up to 20,000 and customised parts in quantities of hundreds of thousands. This form of

manufacturing can be incredibly cost-effective and the process is far more flexible than

conventional manufacturing.

Rapid manufacturing is a technique for manufacturing solid objects by the sequential delivery of

energy and/or material to specified points in space to produce that part. Current practice is to

control the manufacturing process by computer using a mathematical model created with the aid

of a computer. Rapid manufacturing done in parallel batch production provides a large advantage

in speed and cost overhead compared to alternative manufacturing techniques such as laser

ablation or die casting. The true definition of rapid manufacturing involves the production of

series products or the use of the created part in production. Where the part is used in the

development process only then the appropriate term is rapid prototyping.

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2.4 RAPID TOOLING:

Rapid Blocks are standard yet versatile parts that are used to locate pins, rest pads, jig feet, and

other parts in a fixture created with RTC rapid Block can be ordered with different holes such

as tapped holes, drilled and counter bored holes, press fit dowels, or slip fit dowels. When rapid

Block is counter bored; the counter bore is on both sides of the block. The designer can then flip

the block around to meet different needs and spacing constraints.

Rapid Block can have holes in both ends of the block or only one end. A rapid Block with holes

in only one end leaves room for the Machine Designer to modify or alter the end of the block

without holes. Oftentimes Designers will mount a flat foot, rest pad, rapid Plate, or pin in the end

without a hole.

Easy to design into a fixture, rapid Block is also easy to assemble once they arrive at the shop. A

drill point on the face of a block indicates that the dowel holes are slip fit. A face without a drill

point indicates that the dowel hole is a press fit. This helps the machine assembler as they put the

fixture together.

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2.5 INDUSTRIES BEING SERVED:

Companies that use rapid prototyping cut across most manufacturing industries. Consumer

products represent nearly 26%, followed by motor vehicles that represent nearly 24%. The

remaining 50% is comprised of medical, aerospace, business machines and nearly 7% is

attributes to the government/military sectors.

2.6 INSTALLATIONS BY COUNTRY:

The following chart shows the installation system purchased by the country in the year 2007.

USA has the highest

percentage of system installations, followed by japan, Germany and china.

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CHAPTER-3

ADDITIVE MANUFACTURING

2.7.1 STEREO LITHOGRAPHY:

Stereo lithography is an additive manufacturing process which employs a vat of liquid

ultraviolet curable photopolymer “resin" and an ultraviolet laser to build parts' layers one at a

time. For each layer, the laser beam traces a cross-section of the part pattern on the surface of the

liquid resin. Exposure to the ultraviolet laser light cures and solidifies the pattern traced on the

resin and joins it to the layer below.

After the pattern has been traced, the SLA's elevator platform descends by a distance equal to the

thickness of a single layer, typically 0.05 mm to 0.15 mm (0.002 in to 0.006 in). Then, a resin-

filled blade sweeps across the cross section of the part, re-coating it with fresh material. On this

new liquid surface, the subsequent layer pattern is traced, joining the previous layer. A

complete 3-D part is formed by this process. After being built, parts are immersed in a chemical

bath in order to be cleaned of excess resin and are subsequently cured in an ultraviolet oven.

Stereo lithography requires the use of supporting structures which serve to attach the part to the

elevator platform, prevent deflection due to gravity and hold the cross sections in place so that

they resist lateral pressure from the re-coater blade. Supports are generated automatically during

the preparation of 3D Computer Aided Design models for use on the stereo lithography machine,

although they may be manipulated manually. Supports must be removed from the finished

product manually, unlike in other, less costly, rapid prototyping technologies.

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2.7.2 SELECTIVE LASDER SINTERING:

Some SLS machines use single-component powder, such as direct metal laser sintering. Powders

are commonly produced by ball milling. However, most SLS machines use two-component

powders, typically either coated powder or a powder mixture. In single-component powders, the

laser melts only the outer surface of the particles (surface melting), fusing the solid non-melted

cores to each other and to the previous layer.

Compared with other methods of additive manufacturing, SLS can produce parts from a

relatively wide range of commercially available powder materials. These include polymers such

as nylon (neat, glass-filled, or with other fillers) or polystyrene, metals including steel, titanium,

alloy mixtures, and composites and green sand. The physical process can be full melting, partial

melting, or liquid-phase sintering. Depending on the material, up to 100% density can be

achieved with material properties comparable to those from conventional manufacturing

methods. In many cases large numbers of parts can be packed within the powder bed, allowing

very high productivity.

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2.7.3 3-D PRINTING PROCESS:

A large number of additive processes are now available. The main differences between processes

are in the way layers are deposited to create parts and in the materials that are used. Some

methods melt or soften the material to produce the layers, for example. Selective laser

melting (SLM) or direct metal laser sintering (DMLS), selective laser sintering (SLS), fused

deposition modeling (FDM), or fused filament fabrication (FFF), while others cure liquid

materials using different sophisticated technologies, such as stereo lithography (SLA).

With laminated object manufacturing (LOM), thin layers are cut to shape and joined together

(e.g. paper, polymer, and metal). Each method has its own advantages and drawbacks, which is

why some companies offer a choice of powder and polymer for the material used to build the

object. Others sometimes use standard, off-the-shelf business paper as the build material to

produce a durable prototype. The main considerations in choosing a machine are generally

speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and

color capabilities.

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2.7.4 DIRECT METAL LASER SINTERING:

Direct metal laser sintering (DMLS) is an additive manufacturing technique that uses a carbon

dioxide laser fired into a magnesium substrate to sinter powdered material (typically metal),

aiming the laser automatically at points in space defined by a 3D model, binding the material

together to create a solid structure. It is similar to selective laser sintering (SLS); the two are

instantiations of the same concept but differ in technical details. Selective laser melting (SLM)

uses a comparable concept, but in SLM the material is fully melted rather than sintered, allowing

different properties (crystal structure, porosity, and so on). DMLS was developed by the EOS

firm of Munich, Germany.

The DMLS process involves use of a 3D CAD model whereby a .stl file is created and sent to the

machine’s software. A technician works with this 3D model to properly orient the geometry for

part building and adds supports structure as appropriate. Once this "build file" has been

completed, it is "sliced" into the layer thickness the machine will build in and downloaded to the

DMLS machine allowing the build to begin. The DMLS machine uses a high-powered 200 watt

Yb-fiber optic laser. Inside the build chamber area, there is a material dispensing platform and a

build platform along with a recoated blade used to move new powder over the build platform.

The technology fuses metal powder into a solid part by melting it locally using the focused laser

beam. Parts are built up additively layer by layer, typically using layers 20 micrometres thick.

This process allows for highly complex geometries to be created directly from the 3D CAD data,

fully automatically, in hours and without any tooling. DMLS is a net-shape process, producing

parts with high accuracy and detail resolution, good surface quality and excellent mechanical

properties.

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CHAPTER-4

EXPERIMENTAL DATA

4.1 CONVENTIONAL INSERT MODEL:

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4.2 CONFORMAL COOLING INSERT MODEL:

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CHAPTER-5

ANALYSIS BY CONFORMAL COOLING CHANNEL DESIGN

5.1 ANALYSIS OF VARIOUS PARAMETERS:

5.1.1 TIME:

The filling time varies from 0.00 sec to 0.4997 sec.

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The packing time varies from 0.0 sec to 0.4997 sec

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The cooling time varies from 0 to 12.82 sec, but most of the regions take time upto 0 to

4.276 sec.

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5.1.2 AIR TRAP:

The trap position varies places which are mostly towards the border of the part.

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5.1.3 TEMPERATURE:

The temperature is having range 225°C constant

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The packing temperature is having constant range of 225°C.

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The cooling temperature is in the range of 23.023°C to 88.677°C

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5.1.4 SHEAR STRESS:

The filling shear stress varies from minimum of 0.0002 MPa to maximum of 0.404 MPa

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The shear stress is in the range of minimum of 0.00 to 0.0021 MPa of maximum.

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5.1.5 DENSITY:

Following figure shows filling density varies minimum of 0.9752 g/cc at in gate to 0.994 g/cc at

different area.

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5.1.6 SHRINKAGE:

The volumetric shrinkage during filling is in the range of 6.903% to 8.649%

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The volumetric shrinkage during packing is in the range of 6.714% to 6.916%

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5.1.7 PRESSURE:

The pressure during filling is in the range of 0 MPa to 24.064 MPa.

45

The packing pressure is in the range of 21.879 MPa to 23.903 MPa

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5.1.7 COOLING EFFICIENCY:

The cooling efficiency is 100% at all the regions of the channel

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CHAPTER-6

PRACTICAL DATA BY CONVENTIONAL METHOD

DATA:

TIME

Injection Time: 4 sec

Packing Time: 0.5 sec

Holding Time: 0.5 sec

Cooling Time: 10 sec

Total Cycle Time: 15 sec

TEMPERATURE

At Nozzle : 190°C

At Zone-1 : 210°C

At Zone-2 : 205°C

At Zone-3 : 180°C

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CHAPTER-7

PRACTICAL DATA BY CONFORMAL COOLING CHANNEL

DATA:

TIME

Injection Time: 3 sec

Packing Time : 0.5 sec

Holding Time : 0.5 sec

Cooling Time : 3 sec

TEMPERATURE

At Nozzle : 190°C

At Zone-1 : 200°C

At Zone-2 : 180°C

At Zone-3 : 100°C

The Cycle Time :7 sec

The weight of the tool on machine : 1.3 Kg

The total time taken by machine to make the tool: 52 hrs

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CHAPTER-8

CONCLUSION

Conclusion Table:

Cycle Time (sec) Conventional Conformal Cooling

Virtual 21.5 6.5

Particle 15 7

Remarks:

By performing the experiment on conventional and conformal cooling methods we found

the better design is conformal cooling channel which reduce the cycle time with

improved quality standard.

It also shows the effect of both design on productivity as the cycle time is reduced so

productivity is increased.

Cooling channel cross sections can take almost any shape.

Quality of injection moulded parts are improved by better control of the injection system.

A more effective mould temperature control system saves time and costs in the process of

injection moulding process.

The cost of the conformal cooling insert is high due to high cost of material.

The time compare to conventional in conformal method is less with a good quality due to

uniform cooling channel design.

55811_gtu project report 8th sem on rpt

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