1. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
28
NEW APPROACH TO CASTING DEFECTS CLASSIFICATION AND
OPTIMIZATION BY MAGMA SOFT
M. Chandra Sekhar Reddy1*
, Talluri Ravi Teja2
1
Associate Professor,
Department of Mechanical Engineering, UCE(A), Osmania University.
2
Research Scholar, UCE(A), Osmania University.
ABSTRACT
Foundry industry suffers from poor quality and productivity due to the large number of
process parameters, combined with lower penetration of manufacturing automation and shortage of
skilled workers compared to other industries. Global buyers demand defect-free castings and strict
delivery schedule, which foundries are finding it very difficult to meet.
Casting defects result in increased unit cost and lower morale of shop floor personnel. The
defects need to be diagnosed correctly for appropriate remedial measures, otherwise new defects may
be introduced. Unfortunately, this is not an easy task, since casting process involves complex
interactions among various parameters and operations related to metal composition, methods design,
molding, melting, pouring, shake-out, fettling and machining. For example, if shrinkage porosity is
identified as gas porosity, and the pouring temperature is lowered to reduce the same, it may lead to
another defect, namely cold shut.
In this work, we present a 3-step approach to casting defect identification, analysis and
rectification. The defects are classified in terms of their appearance, size, location, consistency,
discovery stage and inspection method. This helps in correct identification of the defects.
Keywords: Casting Defects, Classification, Gating System Design, MAGMA SOFT, Optimisation.
1. INTRODUCTION
Metal casting is one of the direct methods of manufacturing the desired geometry of
component. It is one of the primary processes for several years and one of important process even
today in the 21st century. Early applications of casting are in making jewellery items and golden
idols. Today, casting applications include automotive components, spacecraft components and many
industrial & domestic components, apart from the art and jewellery items.
INTERNATIONAL JOURNAL OF MECHANICAL ENGINEERING
AND TECHNOLOGY (IJMET)
ISSN 0976 – 6340 (Print)
ISSN 0976 – 6359 (Online)
Volume 5, Issue 6, June (2014), pp. 28-35
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2. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
29
The principle of manufacturing a casting involves creating a cavity inside a sand mould and
then pouring the molten metal directly into the mould. Casting is a very versatile process and capable
of being used in mass production. The size of components is varied from very large to small, with
intricate designs. Out of the several steps involved in the casting process, moulding and melting
processes are the most important stages. Improper control at these stages results in defective castings,
which reduces the productivity of a foundry industry. Generally, foundry industry suffers from poor
quality and productivity due to the large number of process parameters, combined with lower
penetration of manufacturing automation and shortage of skilled workers compared to other
industries. Also, Global buyers demand defect-free castings and strict delivery schedule, which
foundries are finding it very difficult to meet.
LITERATURE REVIEW
Basic Principles of Metal casting and Metal casting processes like Sand casting, Die casting
Investment casting and Expendabele Mold Casting and Non Expendabele Mold Casting. Parts of
Gating System Sprues, Runners, Gates, Risers, vents Cores and Drafts. These Studies is done in
Principles of Metal Casting by Richard Heine, Carl Loper, Philip Rosenthal
That is automatic supervision and control of the technological process of manufacturing the
elements from aluminium alloys and of the methodology of the automatic quality assessment of these
elements basing on analysis of images obtained with the X-ray defect detection, employing the
artificial intelligence tools. L.A. Dobrzański and M. Krupiński presented a new methodology in
the paper.
The optimal processing parameters for the cooling were obtained from the analysis of fluid
flow and solidification. Numerical simulations of mold filling and solidification were used to
optimize the casting process. The simulations were used to predict the temperature distributions and
solidification sequences in the casting to optimize the casting conditions. S. M. Yoo, et. al, used to
simulate the fluid flow in a sand mold.
This paper deals with Casting defects in offset printing press cylinder and their remedies
studied by Roby Joy et. al. A printing press is a mechanical device for applying pressure to an inked
surface resting upon a medium (such as paper or cloth), thereby transferring an image.
D.N.Shivappa1 et. al, presented analysis of casting defects and identification of remedial measures
carried out at Dakshin Foundry Ltd, Bangalore, India. Diagnostic study carried out on Trunion
Support Bracket (TSB) Castings revealed that the contribution of the four prominent defects in
casting rejections are sand drop, blow hole, mismatch, and oversize. It was noticed that these defects
are frequently occurring at particular locations.
Casting Simulation and Optimisation has become a powerful tool to visualize mould filling,
solidification and cooling, and to predict the location of internal defects such as shrinkage porosity,
sand inclusions, and cold shuts. This Paper Describes the benefits of Casting simulation.
B. Ravi, 2008, “Casting Simulation and Optimization”, Indian Foundry Journal.
2. PROBLEM STATEMENT
Early in Foundry Industry the defects classified after the manufacturing. By taking that
casting and doing defect testing like Radiography or Ultrasonic Testing Method. In this process the
rejections are 60%.By adding MAGMA SOFT in this process the estimated rejections are 15%.
Every 10 castings 4-6 castings are rejected.
Every time affecting defects are Blow holes, Shrikage, Misrun and Cold shut.
More process variation due to more human involvement which leads to heavy rejection.

3. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
30
Less Automation
Average cost of one casting is Rs.6000/- due to this rejection and again scrap recycle the cost
is almost all 6000/- to 6100/-.
Cost saving through MAGMA
Customers In-Time Dispatch of Castings
3. PRESENT APPROACHES FOR ANALYSIS OF CASTING DEFECTS
At present, casting defect analysis is carried out using techniques like historical data analysis,
cause-effect diagrams, design of experiments. They are briefly explained in this section.
3.1 Historical Data Analysis
To understand this concept, data for occurrence of defects are collected from one of leading
casting manufacturer in Maharashtra for one year. From this data, occurrence chart has been
prepared which further helps to identify occurrence major defects in castings. These data further help
to prepare the chart for occurrence of defect.
Table 1: Historical Data of casting defects
Defects Rejected
Quantity
Job
Rejection %
Defects Rejected
Quantity
Job
Rejection
%
Cold Shut 205 2.03 Cores Broken 16 0.17
Crush 188 2.11 Mismatch 13 0.14
Knock Crack 165 1.85 Sub. Contract
Fettling Fault
10 0.11
Blow Hole 123 1.38 Run Out 7 0.07
Contractor’s
Houling Cracks
55 0.62 Hard 7 0.07
Bad Mold 42 0.47 Slurry
Penetration
4 0.04
Scab 40 0.45 Low Hardness 3 0.03
Fet Crack 32 0.36 Core Scab 1 0.01
Shrinkage 31 0.34 Swell 1 0.01
Slag 23 0.25 Sink 1 0.01
Bad Core 19 0.21 Others 3 0.003
TOTAL 989 11.1012
4. METHODOLOGY
4.1 Present Inspection Methods for Defects
1. Process Inspection
2. Visual Inspection
3. Dimensional Inspection

4. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
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Flow Diagram of Foundry industry
Proposed Flow Diagram using Magma
Start
Core MakingPattern Making
Moulding
2D and 3D
Modeling
MeltingFetllingInspection
Correction in Method
and Tooling
Sample
Submission
MAGMA
Simulation
`Pattern
Making
Start
Core Making
Moulding
2D and 3D
Modeling
MeltingFetllingInspection
Correction in Method
and Tooling
Sample
Submission

5. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp.
• Only 1 Trail below 5% rejection
• No need of trial and error method
• Document evidence on method to the customer
• Reduction in delivery time
• Consistence in the casting quality
• More business on customer satisfaction for early submission to get more orders
4.2 Proposed Gating System Design
PART DESCRIPTION/ DRG. NO: AXLE HOUSING/ YZ 1
RUNNER BAR DIMENSSIONS: 24 X 30 X 45
RUNNAER BAR CROSS SECTIONAL AREA: 1215 mm²
INGATE AREA:
INGATE AREA = 12.08CM²
= 1208 MM² (Considered 1073MM²)
TAKE 3 INGATES
THEREFORE AREA OF EACH INGATE = 358MM²
INGATE DIMENSSIONS: 30X 35 X 11 MM
rnational Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976
6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
32
Only 1 Trail below 5% rejection
No need of trial and error method
evidence on method to the customer
Consistence in the casting quality
More business on customer satisfaction for early submission to get more orders
Proposed Gating System Design
PART DESCRIPTION/ DRG. NO: AXLE HOUSING/ YZ 120704
RUNNER BAR DIMENSSIONS: 24 X 30 X 45
24
45
30
RUNNAER BAR CROSS SECTIONAL AREA: 1215 mm²
H=320mm
C=403mm
P=201.5mm
M=5.93mm
= 1208 MM² (Considered 1073MM²)
THEREFORE AREA OF EACH INGATE = 358MM²
30X 35 X 11 MM
rnational Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
More business on customer satisfaction for early submission to get more orders

6. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
33
SMALL END BIG END MIDDLE END
FLOW OFF DETAILS
ON BIG END: Ø 16 X Ø20 X 85 MM LENGTH 1 NO
ON SMALL END: Ø 16 X Ø20 X 100 MM LENGTH 1 NO
5. GATING SYSTEM
Figure 1: Gating System Proposal 1
GATING RATIO: 1385: 1208: 1073
1:0. 87: 0.77
FILTER DETAILS: 100X 100X 22 MM
FEEDER DETAILS:
ON SMALL END: 10/17K SLEEVE RISER
ON BIG END: 9/17K SLEEVE RISER
MIDDLE: 10/17K SLEEVE RISER.

7. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
34
Figure 2: Gating System Proposal 2
5.1 Gating Geometry
Cad model insert in to the MAGMA soft Start the simulation select the area which it should
be velocity, temperature, speed, solidification and porosity. It will shows which parts the defects are
going to occur(shown in fig.4) so some changes in gating design.
Figure 3: Gating Geometry in MAGMA SOFT

8. International Journal of Mechanical Engineering and Technology (IJMET), ISSN 0976 – 6340(Print),
ISSN 0976 – 6359(Online), Volume 5, Issue 6, June (2014), pp. 28-35 © IAEME
35
5.2 Solidification and Liquid
After analysis of Solidification and liquid of porosity
Figure 4: Porosity spots
6. CONCLUSION
From this study a method is proposed for Defect Prevention like blow hole, shrinkage etc.
Reduction in lead time and sample products is achieved. A suggestion is made for Validation through
MAGMA before manufacture. Cost saving can be done by using through MAGMA, and Customer
In-Time Dispatch
Without MAGMA it will take 3 months to manufacture, whereas with MAGMA it will take 1
month to manufacture.
A Study conducted in Foundry department of Hinduja Foundry Producing Castings. The
Prominent defects occurred in castings were identified by Radiography Testing. After considering
the various aspects, two suggestions were put forward for reducing the defect density. From the two
suggestions, gating system and Magma software implemented. By implementing the suggestions,
15% reduction in rejection rate was estimated.
REFERENCES
1. Anderson, J.V. & Karsay, S.I., 1985., “Pouring rate, pouring time and choke design for S.G.
Iron Castings”. British Foundryman.
2. Gerhardt Jr., P.C. “Computer applications in Gating & Risering System Design for Ductile
Iron Castings” AFS Transactions.
3. Journal by Dr D.N. Shivappa, Mr Rohit, Mr. Abhijit Bhattacharya, “Analysis of Casting
Defects and Identification of Remedial Measures”., Dakshin Foundry ltd.
4. Peter Beeley, “Foundry Technology”, Butter Worth Heinemann, 2nd ed., 2001.
5. B. Ravi, 2008, “Casting Simulation and Optimization”, Indian Foundry Journal, Special
Issue.
6. Richard Heine, Carl Loper, Philip Rosenthal, 1984, “Principles of Metal Casting”, Tata
McGraw Hill Publications, New-Delhi.
7. Cherian Paul and Parvathy Venugopal, “Modelling of Interfacial Heat Transfer Coefficient
and Experimental Verification for Gravity Die Casting of Aluminium Alloys”, International
Journal of Mechanical Engineering & Technology (IJMET), Volume 1, Issue 1, 2010,
pp. 253 - 274, ISSN Print: 0976 – 6340, ISSN Online: 0976 – 6359.
8. M.Narasimha, R.Rejikumar and K. Sridhar, “Statistical Methods to Optimize Process
Parameters to Minimize Casting Defects”, International Journal of Mechanical Engineering
& Technology (IJMET), Volume 4, Issue 3, 2013, pp. 11 - 23, ISSN Print: 0976 – 6340,
ISSN Online: 0976 – 6359.