Design And Optimization Of Runner And Gating Systems For The Permanent Mold Casting.

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA

DESIGN AND OPTIMIZATION OF RUNNER AND GATING

SYSTEMS FOR THE PERMANENT MOLD CASTING

This report submitted in accordance with requirement of the Universiti Teknikal Malaysia Melaka (UTeM) for the Bachelor Degree of Manufacturing Engineering

(Manufacturing Design) (Hons.)

by

MOHAMMAD AIZRULSHAH BIN KAMARUDDIN B050910203

790407-01-6397

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DECLARATION

I hereby, declared this report entitled Design and Optimization of Runner and

Gating for Permanent Casting is the results of my own research except as cited in

the references.

Signature : ……….

Author’s Name : MOHAMMAD AIZRULSHAH BIN

KAMARUDDIN

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APPROVAL

This report is submitted to the Faculty of Manufacturing Engineering of UTeM

as a partial fulfillment of the requirements for the degree of Bachelor of

Manufacturing Engineering (Manufacturing Design) (Hons.). The member of

the supervisory committee is as follows:

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---ABSTRAK

Aliran bendalir memainkan peranan penting dalam menghasilkan acuan tuangan

yang berkualiti tinggi . Aliran bendalir dipengaruhi oleh halaju tuangan dan

pelari(runner) dan reka bentuk pintu (gating) acuan. Ia akan menentukan sama ada

aliran adalah gelora atau lamina. Proses reka bentuk adalah peringkat yang paling

penting dalam mana-mana pengeluaran produk yang sama seperti membuat acuan

kekal . Amalan semasa adalah kaedah cuba jaya untuk mendapatkan reka bentuk

acuan kekal yang terbaik. Dengan menggunakan perisian analisis cecair dinamik,

proses mereka bentuk pelari(runner) dan pintu (gating) boleh dipermudahkan.

Matlamat utama kajian ini adalah untuk mereka bentuk dan mengoptimumkan

pelari(runner) dan pintu (gating) untuk acuan tuangan kekal. Kaedah yang

digunakan dalam kajian ini adalah Solidworks 3D model dan ANSYS FLUENT

perisian pengiraan analisis bendalir dinamik. Model aliran gelora telah digunakan

untuk mensimulasikan aliran aluminium lebur LM6. Empat rekabentuk konsep telah

dianalisa oleh ANSYS FLUENT daripada segi tekanan statik, magnitud halaju,

tenaga kinetik bergelora, tenaga dalaman dan nombor sel Reynolds. Keputusan yang

diperolehi daripada simulasi dioptimumkan untuk mewujudkan acuan yang

sempurna. Kesimpulannya acuan kekal bagi proses acuan tuangan gravity telah

direka dan dioptimumkan dan ia telah memenuhi objektif projek. Analisis simulasi

adalah alat yang sangat berguna bagi jurutera yang boleh digunakan sebagai rujukan

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ABSTRACT

Fluid flow plays a major role in producing good quality casting. The fluid flow is

influenced by the pouring velocity and the runners and gating design of the mold.

The design process is the most important stages in any product manufacturing same

as permanent mold making. The current practice is the experimenting method to

predict the best design. By using computational fluid dynamic analysis the process

of designing runners and gating can be improved. The main objective of this paper is

to design and optimize the runner and gating systems for permanent mold casting.

The method use in this paper is Solidworks 3D modeling and ANSYS FLUENT

computational fluid dynamic analysis software. Transient, turbulence flow model

has been applied to simulate the flow of molten aluminum LM6. The ANSYS

FLUENT analyzed 4 runners and gating design concept from the aspect static

pressure, velocity magnitude, turbulent kinetic energy, internal energy and cell

Reynolds numbers. The results gained from the simulation are optimized to create a

perfect mold. As a conclusion a permanent mold casting was designed and

optimized and it fulfilled the objective of the project. The simulation analysis is a

very powerful tool for engineers that can be used as a reference to improve

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DEDICATION

To beloved wife

Azlinda Mohamad

To my kids

Muhammad Izzu Syahmi and Maryam Kayyisah

And to my parents

Hj Kamaruddin Hj bin Hj Idris

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ACKNOWLEDGEMENT

I would like to thank my supervisor Dr Taufik for the support, guidance and

understanding during the making of this report. Thank to my wife Azlinda for the

patience and understanding. Thank also to my colleague for the idea, discussion and

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TABLE OF CONTENT

2.1 Casting And Its History 5

2.2 Permanent Mold Casting 8

2.2.1 Advantages Of Permanent Mold Casting 9

2.3.1.1. Volume 9

2.3.1.2. Tolerance and Surface finish 9

2.3.1.3. Cost 10

2.2.2 Limitation Of Permanent Mold Casting 10

2.2.3 Defect In Permanent Mold 11

2.2.4 Permanent Mold Casting Process 13

2.3 Design 13

2.3.1 Rigging System Design 15

2.3.2 Riser Design 16

2.3.3 Feeding System In Riser Design 18

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2.3.4.1 Gating Design Variables 19

2.3.4.2 Principle of fluid flow 20

2.3.4.3 Ideal gating design 22

3.3. Stage 2: The Design Stage 32

3.4. Stage 3: Analysis And Result 34

3.5. Stage 4: Report Preparation and Presentation 34

3.6. The Design Concept Sketches 35

3.7. Conclusion 36

CHAPTER 4: RESULT & DISCUSSION

4.1 The Design concept 37

4.1.1 Design concept 1 38

4.1.2 Design Concept 2 39

4.2 Ansys 14 Fluent Simulation 40

4.2.1 Ansys Fluent models 40

4.2.2 Ansys Fluent Material 40

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4.2.2.2 Wall Material 41

4.2.2.3 Cell Zone Condition 41

4.2.2.4 Boundary Condition 41

4.2.3 Ansys Simulation Result Data 43

4.2.3.1 Design Concept 1 43

4.3 Ranking 61

4.4 Optimization 63

4.4.1 The Runner And Gating Concept Design 63

4.4.2 Ansys Simulation Result Analysis 65

4.4.3 Ansys Fluent Flow Analysis Optimized 66

4.5 SolidWorks Modelling 70

4.6 Summary of Result 72

CHAPTER 5: CONCLUSION & FUTURE WORKS

5.1. Conclusion 73

5.2. Future works 74

REFERENCES 75

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LIST OF TABLES

4.1 LM6 Properties 41

4.2 Steel properties 41

4.3 The inlet Condition value 42

4.4 The outlet condition 42

4.5 Simulated Ansys Fluent data 43

4.6 Simulated Data 50

4.9a Design 1 and 2 simulated data 61

4.9b Design 3 and 4 simulated data 61

4.10 Maximum Value comparison 62

4.11 Ranking 62

4.12a Ansys Fluent Result for runner and gating optimize concept 66

4.12b Ansys Fluent Result for runner and gating optimize concept 66

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LIST OF FIGURES

1.1 Gooseneck Clamp 4

2.1 The important development in casting process 6

2.2 Expendable Mold process tree 7

2.3 Process tree under permanent mold casting. Yellow indicates the

scope of study

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2.4 Approximate values of surface roughness and tolerance on

dimensions typically obtained with different manufacturing

processes. ECM, electro-chemical machining; EDM, electrical

discharge machining

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2.5 Differences between manufacturing process 10

2.6a Example defect in the casting process 12

2.6b Example of common defects hot tear in casting. Which the

defect can be minimized or eliminate with proper design and

preparation of molds

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2.7 Directional and progressive solidification in a casting equipped

with a riser

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2.8 Basic component of a single gating system for a horizontal

parted mold

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2.9 Schematic illustrating the application of Bernoulli’s theorem to a

gating system

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2.10 Poor top gates and side-fed running system, compared with (b) a

more satisfactory bottom-gated and top-fed system.

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2.11 (c) Poor system gated at joint and (d) recommended economical

and effective system

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2.12 Comparison of ﬂow patterns in two vertical gating systems. (a) Poorly designed system. (b) Properly designed system using a

tapered runner that equalizesﬂow through the ingates

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2.13 Schematic showing the advantages of a tapered sprue over a

straight-sided sprue. (a) Natural ﬂow of afree-falling liquid. (b) Air aspiration induced by liquidﬂow in a straight-sided sprue. (c)

Liquidﬂow in a tapered sprue

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2.14 Schematic illustrating ﬂuid ﬂow around right-angle and curved

bends in a gating system. (a) Turbulence resulting from a sharp

corner. (b) Metal damage resulting from a sharp corner. (c)

Streamlined corner that minimizes turbulence and metal damage

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2.15 Goose neck clamp

2.16 Technical drawing and dimension of the gooseneck clamp 27

3.1 Project Framework Flow Chart 30

3.2 SolidWorks 3d modelling flow chart 33

3.3 Mold Design outline with SolidWorks 33

3.4 ANSYS 14 Fluent procedures flowchart 34

3.5 Sketch 1 35

3.6 Sketch 2 36

3.7 Sketch 3 36

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4.1 Design Concept 1 37

4.5 Contour of static pressure 43

4.6 Contour of velocity magnitude 44

4.7 Contour of turbulence kinetic energy 45

4.8 Contour of internal energy 45

4.9 Flow simulated 46

4.10 Temperature vs Time Chart 47

4.15 Flow simulated 51

4.21 Velocity Streamline Flow 56

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4.27 Streamline Flow 60

4.29 Gating and runner optimized design 1 63

4.32 Ansys Fluent Streamline for optimized 66

4.34 Streamline Flow for concept 2 optimized 67

4.36 Streamline Flow for concept 3 optimized 68

4.37 Temperature vs Time Chart concept 3 optimized 69

4.38 Mold in close position 71

4.39 Mold Exploded view 71

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CHAPTER 1

INTRODUCTION

This chapter discusses briefly the design and optimization of runner and gating

system for the permanent mold. This chapter of the report briefly discusses the

project background, problem statement, objective and scope.

1.1 Project Background

Casting is an economical and oldest manufacturing process in producing or

reproducing complex part in mass numbers. The first metal casting was found to be

made during the period from 4000 to 3000 BC using stone and metal to cast copper

and bronze (Kalpakjian and Schmid, 2006). Casting is a process in which molten

metal is poured into a cavity of a mold which are split or broken apart to extract the

solidified metal cast(Boothroyd et al. 2002). Designing a mold used in casting is

considered as an art and science. There is no exact formula or parameter can be

used. It depends on the mold designer experiences, trial and error. Casting is divided

into 2 categories which is non permanent and permanent molds. This report covers

the designing and the optimization of runner and gating system for permanent mold

casting.

Permanent mold casting is a method used to cast product or part using permanent

mold or non expendable mold unlike sand casting where the use of expendable mold

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expendable mold means that the mold is usually made from metal. The same

guidelines and rules use in designing a sand casting are applied in designing the

permanent mold. Except that in sand casting if there is an error or modification in

the design the mold can be crushed and reconstructed, this method did not apply to

permanent mold where it will require metal cutting and reshaping (Shamasundar et

al., 2010.). This will require cost therefore permanent mold need to be designed

carefully. Due to the material used for making the mold, it usually being used to cast

non ferrous alloy and some limited application for casting cast iron. Typical material

can be cast using permanent mold is aluminum, zinc, brass, copper, lead and even

gray cast iron. The benefit of using permanent mold casting is that the high

production runs due to faster cooling rate than sand. Permanent mold casting also

produces a product with high dimensional accuracy, near net shape and use less raw

material. Reasonable price cost can be achieved from the high production rate with

metal molds especially the water cooled molds compare to sand or investment

casting (Butler, 1998). Limitation of permanent mold casting is that not all shapes

can be cast using it, but with the combination of detachable and expendable core the

potential is limitless.

Defect effecting sand casting also applies to permanent mold casting such as

porosity and shrinkage. In order to eliminate the defect, the mold to be designed

carefully. Design is the critical step in the development of cost effective, high

quality casting. In designing a good permanent mold the part geometry plays a big

role in effecting the load carrying functionality of the casting but also the mold

construction (Stoll, 2009). The main purpose of designing the molds is to

concentrate liquid solid contraction until to the last portion of the casting to solidify

(Lampman, 2009). In the production of permanent mold the design or the

development stage use a lot of resources but quickly offset by the high production

run. A Goose neck machine clamps used for this study. Then the molds are design

using CAD software, the designed mold were tested using an analysis software.

Later the design will go optimization process. This project presents the design of

permanent mold use for casting a production tooling. The study on making a

permanent mold will give a lot in sight in the best method in the manufacturing of

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1.2 Problem Statement

Designing permanent molds for casting can be considered as art and science.

Runners and the gating system are the most important part of the mold. There a

numerous guideline can be used for designing a mold but the position and size of the

runner and gating depended on the part want to cast. At the moment the current

practice in mold construction is an experimenting method where base on trial and

error. The trial and error method solely depended on the design engineers

knowledge and experience. However this practice is time consuming and high cost.

In this report the product use for study is a Goose neck machine clamp. Finding the

position and size of the runner and gating system is crucial to produce defect free

product and near net shape as possible. This project presents the design of

permanent molds, design and analyze using Computer Aided Engineering software.

1.3 Objective

1.3.1 To investigate the design parameter of a permanent mold casting for Goose

neck machine clamp.

1.3.2 To analyze and optimize the permanent mold casting Computer Aided

Engineering software.

1.3.3 To design a permanent mold casting for Goose neck machine clamp.

1.4 Scope

This report only focuses on mold design of a production tooling called Goose neck

machine clamp. The report also considers the existing optimum parameters for

casting molds. The mold geometry design using SolidWorks design software and

analyze using the ANSYS FLUENT software. The mold designed is for gravity

feed casting. Aluminum LM6 and stainless steel is use as the molten metal and mold

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Figure 1.1 Goose neck clamp

1.5 Report Structure

Chapter 1 describes the background of the study. Chapter 2 consists of the literature

review and chapter 3 the methodology of the research project. Chapter 4 explained

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CHAPTER 2

LITERATURE REVIEW

This chapter consists of the information gathered regarding the project title which is

Design and optimization of runner and gating system for permanent mold casting.

The information collected from books and previous study. Tools and software used

in this project also will be explained in this report.

2.1 Casting And Its History

Casting can be considered as an oldest manufacturing method know to man. It's a

method used to produce parts in mass numbers. Casting was first used around 4000

B.C to cast ornament and copper arrow head (Kalpakjian and Schmid, 2006).

Copper is the first metal to be cast and usually the component made were weapon

arrow head or axes. During the Bronze Age (3000-1500 BC) alloys such as tin

bronze and arsenical copper were developed. Alloying, as well as reducing the

melting temperatures required, improved the strength of the finished product and

helped to oxidize the melt, enabling a better surface finish and higher level of detail

to be obtained because of the enhanced fluidity (Jolly 2003).

There some archeological find and the oldest casting in existence is a copper frog

dated 3200 BC discovered in Mesopotamia. One of the first cast iron objects, a 270

kg tripod, was cast by Chinese in 600 BC. A colossal statue of the Great Buddha in

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There is also some developed at about the

small object mainly

investment casting. T

process.

Figure 2.1

some archaeological evidence that the “lost w

bout the beginning of the Bronze Age. This method

nly jewelry (Jolly 2003). Later on this method

. The figure 2.1 below show the important deve

2.1 The important development in casting process (Jolly

ost wax” process was

hod was used to cast

hod was renamed the

velopment in casting

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Casting can be used to produce a wide variety of product with complex shape and it

only involves one major manufacturing method. Casting involves pouring molten

metal in a mold cavity that configured to the shape and dimension of the intended

finish product. Casting can be divided into 2 major categories which is expandable

and non expandable mold. Figure 2.2 below illustrates the process tree under the

expandable mold process

Figure 2.2 Expendable Mold process tree

As the name implies the expendable mold process use material that are expendable

such as sand or other granular mold material. In expendable mold casting with

permanent pattern the mold needed be split into in order to remove the pattern

before the actual pouring process is done. Due to the title of the project the

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2.2 Permanent Mold Casting

Permanent mold casting is a casting process that uses non expendable that are either

made from metal or graphite. Permanent mold processes involve the production of

castings by pouring molten metal into permanent metal molds using gravity, low

pressure, vacuum or centrifugal pressure and simple reusable cores are usually

made of metal (Lampman, 2009). The mold cavity and the gating system are

machined into the mold and become an integral part of the mold (Kalpakjian and

Steven, 2006). That's why the design of the mold is crucial. Figure 2.3 illustrated the

process tree under permanent mold casting process.

Figure 2.3 Process tree under permanent mold casting. Yellow indicates the scope of study.