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Page 1
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Technical Presentation
Green sand Molding Management
Page 2
01 Oct 2011, Suranaree University of Technology,
Nakhon Ratchasima
Prepared by U. Ittipon
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INTRODUCTION
-Green Sand Molding process (bentonite bonded sand)
-Chemical Sand Molding process
CO2 Mold (Sodium Silicate binder)
Types of Molding process
Page 4
Shell Mold (Phenoric resin binder)
Furan Resin Mold (Furan resin binder)
Cold Box (Polyurethane resin binder)
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INTRODUCTION
-Reasonable cost.
-Environmental friendly.
-High productivity (Economical)
Why we use Green sand Molding process
Page 5
-Easily adaptable to manual , semi-auto and automatic
molding Machine.
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INTRODUCTION
Green sand Molding process
Jolt Squeeze _Video file
Page 6
Automatic Moldingmachine _Video file
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SAND SYSTEM
Core makingNew Sand
ResinsCore wash
Bentonite
AdditivesWater
New Sand
PREPARATIONHomogenization
HydrationMixing
MOLDINGVertical or Horizontal
DustExtraction
CIRCULATION
Aerator
[Increase ofCompactibility]
Page 8
Sand Losses
COOLING POURING
Sand extracted
Sand adhering to castings
SHAKEOUT(Drum or Vibratory)
Screening
Magnet.Separator
SYSTEM
Increase of sandtemperature
Burnout of Clayand Sea Coal
Gas emissions
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CASTING DEFECTS
Castings defects relative to Green Sand Moulding could be due to :
- The COMPONENTS of the Green Sand for Moulding
- The PROPERTIES of the Green Sand for Moulding
- The UTILIZATION of the Green Sand for Moulding
Page 9
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FOUNDRY SAND
SILICA CHROMITE ZIRCON OLIVINE
Formula SiO2 FeO Cr O3 Zr Si O42 (MgFe) O
SiO2
Specific Density 2.65 4.3 4.7 3.5
Bulk density 1.6 2.7 2.8 1.95
Available Materials
Page 11
Sinterpoint 1730 2095 >2200 1857
Thermal
conductivity Low High High Low
Reaction
mold/metal High Low Low Low
Utilisation All metals Steel &
Manganese Steel Steel
Disponibility High Very low Very Low Good
Price Low High High Medium
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SILICA SAND
Material used for its Economic advantages andsufficient thermal resistance
Important characteristics: The Grain size
Page 12
The Grain surface shape
The thermal resistance
(sinter Point) Silica content
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Main components:SiO2 = Min 98 %
Al2O3 = Max 0.13 %
Fe2O3 = Max 0.06 %
Physical properties:
Grain size Distribution
10
15
20
25
30
35
40
45
50
Individualresiduein%
SILICA SAND
Page 13
= .
Hardness = 7
pH = 7
LOI = Max 0.15%
Moisture = Max 0.1%Sinter point = Min.1500 Co
0
5
600 425 300 212 150 106 75 53 Pan
Sieves opening in Microns
AFS No = 55 - 603 Screens Distribution with 80 % min on
cumulative ASTM sieves 50, 70, 100
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AFS GRAIN FINENESS
SILICA SAND
70 AFS
0
10
20
30
40
5060
70
80
90
100
Residue%
72 AFS
0
10
20
30
40
50
60
70
80
90
100
Residue%
Page 14
6 20 40 70
140
270
6 20 40 70 140
270
70 AFS
0
5
10
15
20
25
30
35
40
6 12 20 30 40 50 70 100
140
200
270
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Thermal expansion
Temperature Crystallographyof SiO2
Density Expansionrate
SILICA SAND
Page 15
Ambient Quarz 2,65 = F (oC)
573 oC Quartz 2,49 1,5%
867 oC Tridymite
1470 oC Cristobalite 2,33 3~5%
1730 oC Amorphous Silica
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Thermal expansion
SILICA SAND
SILICA
ZIRCON
OLIVINE1
2
nsio
Page 16
CHROMITE
-1
0
020
0400
600
800
1000
1200
1400
Degrees Celsius
%Exp
Bentonite
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Foundry sand Bentonite
GREEN SAND COMPONENTS
Page 17
WaterAdditives
Dead Clay
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RULE OF BENTONITE = THE SAND BINDER
Sand Grains x 3800
Page 18
(bridge between sand grains)
Sand Grains
Bentonite
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WHAT IS BENTONITE?
Bentonite is a type of clay whose main constituent isMontmorillonitebelonging to the smectite group.
CLAYS(app. 200 types)
1/1 GROUP
Primary layers 7
2/1-1 GROUP
Primary layers 14
2/1 GROUP
Primary layers 10
Sub-groups and families Sub-groups and families Sub-groups and families
Other Clays family
[Tetrahedral - Octahedral Tetrahedral] Layers
Other Clays family Other Clays family
Page 19
SMECTITE FAMILY
Sub-groups and families
MONTMORILLONITE:
Other Clays family Other Clays family
Clays Classification
Division : particles size less than 2 microns
Appearance : no symmetrical particles with lamella tendency.
Dispersion : possibility to make colloidal suspension with more orless stability in water
Chemical formula : alumina silicates
[Hydrated Alumina and Magnesia silicates]
[Rk: 1 micron = 10,000 Angstrom units ()]
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Natural Treasure
WHAT IS BENTONITE?
Montmorillonite has been identified in France by Mr. Damour and Mr. Salvetat
in 1847 on a small mine nearby Montmorillon city (France).
Page 20
The first industrial exploitation at the beginning of the 20th Century started at a
mine located near Fort Benton in Wyoming province (USA). This explains the
origin of the term Bentonite which was first a trade name.
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Bentonite is a relatively soft stone,
formed over geological time by the
natural alteration of volcanic tuffsdue to acid or alkaline rain.
WHAT IS BENTONITE?
Page 21
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Ca++
Aluminium dioctahedral layerApp.10
LATTICE STRUCTURE
Na+ Na+
Silicon-Oxygen tetrahedral layer
Silicon-Oxygen tetrahedral layer
Page 22
a+a+
Na+
Aluminium dioctahedral layer
Silicon-Oxygen tetrahedral layer
Silicon-Oxygen tetrahedral layer
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In the nature, existing exchangeable cations are:
calcium => Natural Calcium Bentonite
sodium => Natural Sodium Bentonite
BENTONITE MINES
Most exploitable mines in the world are Natural Calcium Bentonite
Page 23
,
cation by Na cation .
This operation is called ACTIVATION PROCESS that consist in
mixing bentonite with soda ash, combining specific moisture, mechanical
treatment and temperature conditions.
After activation, processed bentonites are called:
Activated Sodium Bentonites.
By passprocess
By passprocess andcharacteristics
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BENTONITE : LAYERS STRUCTURE
Page 24
The space between the layers is maximum with Na-Ions
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BENTONITE - MILLING
Granules
Box Feeder
Cyclonesystem
[ Material Flow Milling ]
Page 25
Finish Product
Raymond
Mill
QualityControl
QualityControl
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BENTONITE : FROM MINING TO FOUNDRY
Mining StockingExploitation
Page 26
Activation Drying Milling(PM 12)
Packing
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BENTONITE : FROM MINING TO FOUNDRY
Raw Material
Drying
Activation / Extrusion
Raw Material Stocking
Mining Exploitation
Mining Exploration
Granules
Page 27
Finish Products Stock
Milling / Drying
Granules Stocking
Finish Product
Packing
Delivery to Foundry Industry
QualityQualitycontrolcontrol
Foundry
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BENTONITE : LABORATORY CONTROL
Swelling VolumeSwelling Volume Water contentWater content Particle sizeParticle size
Page 28
Wet Tensile Strengths & Green Compression StrengthsWet Tensile Strengths & Green Compression Strengths
Methylen Blue RetentionMethylen Blue Retention VDG PVDG P 6969NormNorm
MethodMethod
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swelling volume ml / g
20
BENTONITE : MAIN CHARACTERISTICS
-Swelling: one of the main characteristics of Montmorrillonite is to fix water molecules between thelayers which causes the inner structural water. Swelling highly depends on the nature and quantity of the
exchanged cations but also on the % of Na2CO3 for Activated Sodium Bentonites.
Page 29
5
10
15
17
0
5
10
15
0 2 4 6 8
activation rate : % soda ash
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-Swelling:
BENTONITE : MAIN CHARACTERISTICS
Page 30
% Na2CO3activation changes according to the origin and content of Montmorrillonite
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Control of the Activation = Wet Tensile Strength
BENTONITE : MAIN CHARACTERISTICS
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- Montmorillonite content:The montmorillonite content is improperly associated to the measurement of the Methylene Blue
Retention. Other methods are difference of density or X-ray diffraction. A calibration is possible to make a
link between the % of Montmorillonite and the MB retention. Professionals agreed to call bentonite, all
clays with Montmorillonite content over 60%.
- Methylene Blue Retention = method based on the retention capacity of Montmorillonite by
the molecules of dyestuff the Methylene Blue. In fact, this test indicates the specific surface of bentonite.
BENTONITE : MAIN CHARACTERISTICS
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- Water content:2 types of water must be considered in case of Montmorillonite:
- Bonding water (existing in the lattice network structure)
[ evaporation from 100 OC ] = important factors because:
- Exceeding, it can lead to plugging in the pneumatic transport system
- Too low means bentonite will be difficult to re-hydrate
BENTONITE : MAIN CHARACTERISTICS
Page 33
- Constitution water in the macroscopic primary layers network
[ influence on the durability of bentonite - evaporation around 500 OC ]
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- Particle Size: measure of the sieve residue at 75m with specific equipment.
BENTONITE : MAIN CHARACTERISTICS
Page 34
- Too coarse particles can affect the speed of the water absorption.
- Too fine particles can affect the consumption of bentonite (lost in dust collectors)
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- Carbonates content:The purpose is to determine the Total carbonates. (all carbonates existing in the bentonite ie. Na, Ca, Mg,
etc). This process is not to control the activation level but the consistency of the bentonite.
[The volume of CO2
given off when attacked by hydrochloric acid. Results are expressed in CaCO3
].
- Cohesion characteristics:
The ur ose is to measure the bindin ca acit of bentonites. These characteristics will be measured b
BENTONITE : MAIN CHARACTERISTICS
Page 35
introducing another component - Silica sand.
Rk = Control receipt on bentonite = VDG P 69 Din Method as mixture of 100 parts silica sand (AFS 55-
60) with 5 parts bentonite and necessary water to get 45% Compactibility.
- Test of Compressive Strengths, Shear Strengths, Wet Tensile strengths.
BENTONITE MAIN CHARACTERISTICS
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- Durability:Capacity of the bentonite to loose its water more or less quickly.
3 methods can be applied:
1- Testing the cohesion characteristics on bentonite heated at 550OC (1/2 H in ventilatedfurnace) based on the VDP 69 Din Method. Durability is the % of drop between the characteristics
before and after heating.
BENTONITE : MAIN CHARACTERISTICS
Page 36
- .
0
50
100150
200
250
300
350
400
450
0 100 200 300 400 500 600 700 800
temperature C
MBR
mg/g
bentonite 1
bentonite 2
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Foundry sand Bentonite
GREEN SAND COMPONENTS
Page 37
WaterAdditives
Dead Clay
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When molten metal is poured, the moulding sand undergoes somemodification that influence casting quality:
Liquid metal could penetrate in the green sand interstice
(Metal penetration defects)
The mould atmosphere is wet and couldoxidize the metal.
LUSTROUS CARBON FORMER
Page 38
the casting surface alteration.
Solution :Addition of Lustrous
Carbon Former
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Feature Coals Resins
LOI, %
Sulphur content, %
Nitrogen content, %
92 to 96
0,4 to 0,8
1,2 to 2,6
98 to 100
0,1 to 0,3
0,1 to 3,0
Basic data for Coals and resins (asphalt) suitable for the production of lustrous carbon:
LUSTROUS CARBON FORMER
Page 39
Volatiles, %
Swelling Index
(according to DIN 51741)
Lustrous Carbon, %
Surface quality
34 to 40
2 to 7
9 to 14
Moderate to very good
76 to 98
0
36 to 44
Only in combination with
sea coal, good toexcellent, especially with
thin wall castings.
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ECOSILLustrous carbon former, (sea coal)Lustrous carbon former, (sea coal)is added to green sand in order to :is added to green sand in order to :
prevent metal penetration.
obtain a smooth casting surface.
lessen the incidence of expansiondefects (silica sand dilution).
reduce the mould-wall movementand formation of shrinka e
Page 40
cavities.
create excellent breakdowncharacteristics of the mould uponshakeout.
reinforce and to stabilise thegreen strength properties ofmoulding sand.
A S
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To improve moulding sand properties as:
- Elasticity (sand deformation)
ADDITIVES
Organic Carbohydrates - Starch
Page 41
-
In specific cases, could compensate the expansion of silica grains (in
fact to reduce expansion defects as scab, rat tail, veining, etc)
GREEN SAND COMPONENTS
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Foundry sand Bentonite
GREEN SAND COMPONENTS
Page 42
WaterAdditives
Dead Clay
WATER
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WATER
One of the most influent element.
Development of the Moulding Sand Properties
Page 43
Contains impurities that affect the bentonite properties
WATER : INFLUENCE OF SALTS
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NaNa++
NaNa++
WATER : INFLUENCE OF SALTS
Salt de-actives the
bentonite electrostatic
Normal
Page 44
NaNa++
NaNa++
ClCl--
bonding properties
COMPOSITION : INFLUENCE OF WATER
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COMPOSITION : INFLUENCE OF WATER
De-activation phenomenon could be verified by the WTS test.
Page 45
COMPOSITION
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Foundry sand Bentonite
COMPOSITION
Page 46
Dead Clay
AdditivesWater
DEAD CLAY
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The part of bentonite heated above 500OC loses its structural water and settles itself on
the sand grain.
This bentonite loses permanently its properties and becomes a dead clay.
At each sand circulation, a part of the sand grains is coated by this dead clay. This isthe Oolitisation process .
Dead clay reduces the expansion of the green sand and permits to fix a part of the free
Oolitisation process
Page 47
water n t e mo .
Dead Clay
High Oolitisation Low Oolitisation
COMPOSITION
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100 % = (Silica sand+Dead Clay) + (Active Clay+Combustibles) + Water
RefractoryAbsorbents
Catalyst
GREEN SAND MOULDING FORMULA
100 % = SiO2 + DC + AC + LOI+ H2O
Page 48
The Green Sand Formula depends mainly on:
- the type of sand plant (mixer, cooling system, etc..)
- the type of moulding process
- the type of shake-out process- the materials used (new sand, bentonite, additives, etc)
- the castings produced (sand/metal ratio, type of metal, etc..)
COMPOSITION
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100 % = (Silica sand+Dead Clay) + (Active Clay+Combustibles) + Water
GREEN SAND MOULDING COMPOSITION
Generally, the moulding sand is made up with :
Iron Castin s Steel Castin s
Page 49
SiO2= 75% to 85% SiO2= 75% to 85%DC= 5% to 8% DC= 6% to 9%
AC= 6% to 10% AC= 8% to 12%
LOI= 3% to 5% LOI= 2% to 3%H2O= 2% to 4% H2O= 2% to 4%
CONTROL THE COMPOSITION
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1- Active Clay (using Methylene-blue method)
The AC determines the quantity (in %) of bentonite that is able to bond the sand
grains. The AC represents the bentonite that could absorb a methylene-bluesolution.
The AC content mainly depends on:
Page 50
The type and origin of bentonite(MB retention of the bentonite in use in the
sand system) up-date its value regularly and calibrate each new MB solutionbefore dosage
The durability of the bentonite (thermal resistance)
The type of metal pouring (grey iron, ductile iron, steel, etc..)
The Foundry equipments (molding process, mixing process, cooling process,
shake-out process)
CONTROL THE COMPOSITION
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2- Loss on Ignition (LOI)
The LOI determines any element burnt at 900oC that is the combustible materials
in the green sand system. In fact, LOI relates to the carbon former (seacoal), thestructural water of bentonite, the carbonless of core sand, etc.
LOI permits to estimate the exchange of sea coal in the sand system.
Page 51
The LOI content mainly depends on:
The type and origin of sea coal (composition of the original sea coal added in
the sand system),
The quantity and type of core sand
The type of metal pouring (grey iron, ductile iron, steel, etc..)
The Foundry equipments (shake-out process and dust collectors)
CONTROL THE COMPOSITION
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3 Water content
The Water Content is one of the most important and easiest test. Water content
affects every properties of green sand, but mainly permits to swell the bentonite.
The test represents the water loss at 105oC.
Control sometimes its pH, conductivity (
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4 Silica and Dead clay content
The silica and dead clay represent the refractory part of the green sand.
Dead clay is the bentonite that has lost its structural water.
The Silica content mainly depends on:
The type, origin and quantity of foundry sand and core sand in the system. (Vs
the sintering point of original foundry sand)
Page 53
The Dead clay content mainly depends on:
The type, origin and durability of the original bentonite added in the sand
system,
The type of metal pouring (grey iron, ductile iron, steel, etc..)
The quantity of silica sand added in the system.
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Page 56
PROPERTIES
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First ControlFirst Control
Page 57
Compactibility = Plastic or not?
Water content = Dry or wet sand? Temperature = Hot or cold?
Strengths = Brittle or not?
PROPERTIES : COMPACTIBILITY
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The compactibility indicates the water tempering degree of the green sand moulding.
Represented by a percentage number, the compactibility test determines the
decrease in height of a loose mass of sand under the influence of a controlled
compaction.
The compactibility is directly related to the sand quality or the performance of a molding
sand mixture.
The following factors affect the compactibility :
Page 58
The mixing time (calibration and mulling energy)
The Active clay and LOI levels
The inert fines (fines from silica absorbing water)
The quality of Bentonite (Swelling capacity, water holding capacity)
The quality of sea coal (type of coal and coke transformation capacity )
The used of starch and Cereals (change the bonding properties) Video. file
COMPACTIBILITY
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40
42
44
46
Dry sand
OK
Wet sand50 mm1
Compactibility %
Page 59
32
34
36
38
Sand Specimen CompactibilityWater Content %
PROPERTIES : COMPACTIBILITY
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40
42
44
46
Compactibility %
7 % 8 % 9 %
Active clay (MBR) %
Page 60
32
34
36
38
Water content %
PROPERTIES : STRENGTH
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The mould sand strength can be expressed by several standard tests :
Green Compression Strength :
Wet Tensile Strength
Dry Compression Strength
Page 61
But also : green shear strength, resistance to fissuring, resistance to abrasion,
etc
They depend on the composition and the preparation of the moulding sand
PROPERTIES
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Green compressive strength - GCS: (N/cm2)The working strength of molding sand is a combination ofcompressive strength and deformation or mold plasticity ( Keep mold
wall stability).The most influential factor in controlling GCS is the temperingmoisture eneral com osition t e and amount of Bentonite binder
Page 62
and degree of mulling ( Active clay and moisture ratio)Green tensile strength: mostly effect to mold wall stability ofhorizontal molding on cope side.
Green Shear strength: mostly effect during remove the pattern or putcore in Mold.
Test Simpson _Video file Test Rid _Video file Test Shear _Video file
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Strengths: Problem zones of bentonite bonded sand
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Form Compacted moulding sandCondensation zoneForm - Dried and Burnt moulding sandLiquid Iron
Strengths profile during the heat penetration into mouldsStrengths profile during the heat penetration into moulds
Heat penetration intoFoundry Mold
Page 64
FormForm-- Dried sandDried sand
FormForm Tempered MoldingTempered Molding
sandsand
StrengthsN
/cm2
FormForm-- Dried sandDried sandPermeability
Distance to the liquid metal (mm)Distance to the liquid metal (mm)
Molten
Metal
Molten
Metal
Dry tensile strengths
Green strengths
CondensationCondensation
zonezone
CondensationCondensation
zonezone FormForm Tempered MoldingTempered Moldingsandsand
Permeability through different zones of moulding during pouring processPermeability through different zones of moulding during pouring process
WTS Area
- - - - Effect of Starch
PROPERTIES : PERMEABILITY
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The permeability indicates the ability of the gas to escape through the mould
The permeability is directly related to the sand composition
The following factors affect the permeability :
The water content
The silica sand AFS index and its repartition
Page 65
The Active clay, dead clay and LOI levels
The inert fines (fines from silica absorbing water)
The used of starch and Cereals
The moulding machine
The shake-out
Green Sand Molding test report
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Page 66
Green Sand Molding test report
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Page 67
Materials Consumption Vs Cast Iron Quality
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Iron Sand ratio
Heat penetration into mold
Page 68
New sand Consumption
Bentonite Consumption
Coal Dust Consumption
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FOUNDRY
Page 70
MOULD
Pouring
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Page 71
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Page 73
Condensation ofthe water:
Formation of wet layers
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Page 74
Heat Radiation from liquid metal
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Reducing Atmosphere
Page 75
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Formation of aLustrous carbon filmLustrous Carbon FilmLustrous Carbon Film
Page 76
Gas Cushion
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FOUNDRYCCASTINGCASTING
Page 77
ASTING
SAND BURNT Wet layers
Influences : Iron Sand Ratio
Foundry Example
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Foundry Example
Iron-Sand ratio = 1:10
Sand Replenishment = 90 kg/t Fe
Bentonite consumption = 45 kg/t Fe
Coal dust consumption = 18 kg/t Fe
Page 78
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Influences
Foundry Example
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y p
Iron-Sand ratio = 1:10
Sand Replenishment = 90 kg/t Fe
Bentonite consumption = 45 kg/t Fe
Coal dust consumption = 18 kg/t Fe
Page 80
Influences
Foundry Example
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y p
Iron-Sand ratio = 1:10
Sand Replenishment = 90 kg/t Fe
Bentonite consumption = 45 kg/t Fe
Coal dust consumption = 18 kg/t Fe
Page 81
Bentonite-bonded molding sand Balance
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Why a Balance is necessary:
to maintain a constant composition of the green sand molding
to stabilize the properties of the green sand molding
to control the right utilization of the green sand molding
to simulate a specific future condition or future phase of
development
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Circulation system General principle
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Page 84
From this relation, it can be determined how high the percentage of a newly added material is,at a specific time.
Core makingBentonite New Sand
Application to the sand circulation system
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New SandResins
Core washSea CoalWater
PREPARATIONHomogenization
Hydration
Mixing
MOLDINGVertical or Horizontal
DustExtraction
CIRCULATION1. Time needed per sand circulation
2. Number of circulations per working
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Sand Losses
COOLING POURING
Sand extracted
Sand adhering to castings
SHAKEOUT(Drum or Vibratory)
Screening
Magnet.
Separator
Burnout of Clayand Sea Coal Increase of sand
temperature Gas emissions
SYSTEM
time (hour/day/shift).
3. Exchange rate of materials percirculation at a specific time
Application to the sand circulation system
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When considering the total moulding sand system,
-A0is thetotal amount of sand in the systemas [sum of the sand in the machine bunkers, in the usedsand silos, on the cooling conveyor, etc].
-BZis thesum of all additivesas [new sand +recovered core sand + bentonite + sea coal]
-Bnis thepercentage of all new additivesin the total sand system aftern circulations.Bn is the part of the total sand that has been exchanged by the total new additives after ncirculations.
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Circulation: During a circulation x parts of Material (B) is added to an amount of Material (A) andthe same quantity (x parts) is drawn out of the system. After this both materials are homogenised.
Addition:Material (B) is added, x is the quantity added as a percentage of the amount of material(A).
Exchange: After n circulations there remains 100% material (B). Material (A) is completelyexchanged.
Application to the sand circulation system
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Page 87
UTILIZATION : green sand circulation report
The green sand circulation system report : essential
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driver for technicians
Follow the consumption
of your additives in kg/Tof liquid metal0
510
15
20
25
30
35
40
seacoalandbentoniteconsumption
0
20
40
60
80
100
120
140
160
180
sandsconsumptio
New sand 2 2. 0. 0. 7. 20 35 42 482416 15 1120 15 4. 1. 5.
J
a
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F
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b
M
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A
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O
ct
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FOUNDRY XXX - Additivesconsumption in kg/T of liquid metal
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Be aware of :
-Sand system circulation speed
-Regeneration of additives
-Changes of additives formula
Core sand 62 61 6253 58 61 53 63 7860 68 81 52 67 7162 57
Seacoal 5. 5. 7. 7. 8. 10 7. 7. 6. 9. 5. 6. 6. 5. 5. 5. 6.
bentonite 33 32 2528 29 25 29 28 2730 24 29 30 26 3032 30
UTILIZATION : Data collection (example)
ADDITIVE RATIO ON JANUARY-FEBRUARY 2007
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Total mix Sand Bentonite Sea coal Core Sand Melting Sand Bentonite Sea Coal Core Sand
- Mt - Recovery
08/01/2007 590 5900 6490 1180 13367 140.6 41.97 46.17 8.39 76.1 118.05 46.17 8.39
09/01/2007 587 5870 6457 1174 14631 154.0 38.12 41.94 7.62 76.0 114.14 41.94 7.62
10/01/2007 519 5190 5709 1038 13529 122.4 42.39 46.63 8.48 88.4 130.80 46.63 8.48
11/01/2007 522 5220 5742 1044 9901 118.2 44.18 48.60 8.84 67.0 111.22 48.60 8.84
12/01/2007 579 5790 6369 1158 10890 136.5 42.41 46.65 8.48 63.8 106.23 46.65 8.4815/01/2007 673 6730 7403 1346 12034 147.7 45.56 50.12 9.11 65.2 110.74 50.12 9.11
16/01/2007 529 5290 5819 1058 8978 127.4 41.53 45.69 8.31 56.4 97.93 45.69 8.31
17/01/2007 599 5990 6589 1198 15304 160.7 37.27 41.00 7.45 76.2 113.45 41.00 7.45
18/01/2007 577 5770 6347 1154 12820 141.4 40.80 44.88 8.16 72.5 113.31 44.88 8.16
ADDITIVE RATIO ON JANUARY-FEBRUARY 2007Consumption Consumption ratio ~ kg per Mt Melting ~
Date Total Sand Total Bentonite Total Seacoal- kg - Actual
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. . . . . . . .
22/01/2007 635 6350 6985 1270 11017 145.2 43.74 48.11 8.75 60.7 104.44 48.11 8.75
23/01/2007 632 6320 6952 1264 11581 153.1 41.29 45.42 8.26 60.5 101.83 45.42 8.26
24/01/2007 646 6460 7106 1292 10765 151.0 42.77 47.05 8.55 57.0 99.80 47.05 8.5525/01/2007 621 6210 6831 1242 10633 151.1 41.09 45.19 8.22 56.3 97.36 45.19 8.22
26/01/2007 597 5970 6567 1194 10066 148.7 40.14 44.15 8.03 54.1 94.28 44.15 8.03
28/01/2007 250 2500 2750 500 6411 58.6 42.64 46.90 8.53 87.5 130.11 46.90 8.53
29/01/2007 523 5230 5753 1046 8348 126.2 41.46 45.60 8.29 52.9 94.40 45.60 8.29
30/01/2007 533 5330 5863 1066 8566 120.2 44.34 48.77 8.87 57.0 101.34 48.77 8.87
31/01/2007 570 5700 6270 1140 11241 151.8 37.56 41.31 7.51 59.3 96.81 41.31 7.51
TOTAL 10828 108280 119108 21656 212250 2599
AVG 570 5699 6269 1140 11171 136.8 41.79 45.97 8.36 66.02 107.81 45.97 8.36
SD 90.61 906.10 996.71 181.22 2232.13 22.77 2.33 2.56 0.47 10.76 10.85 2.56 0.47
UTILIZATION : Consumption report (example)
FOLLOW-UP OF THE CONSUMPTION'S RATIO
Foundry sand SPEC = 150-250 kgkg / Mt of liquid Metal pouring
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50.00
60.00
70.00
Bentonite SPEC = 40-60 kgkg / Mt of liquid Metal pouring
50.00
75.00
100.00
125.00
150.00
175.00
200.00
225.00
250.00
08
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09
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29
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30
/01/2
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31
/01/2
007
Foundry sand SPEC = 150 250 kg
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20.00
30.00
40.00
.
08/0
1/2007
09/0
1/2007
10/0
1/2007
11/0
1/2007
12/0
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13/0
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30/0
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31/0
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5.00
10.00
15.00
20.00
25.00
08/0
1/2
007
09/0
1/2
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10/0
1/2
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11/0
1/2
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12/0
1/2
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13/0
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14/0
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17/0
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18/0
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20/0
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21/0
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22/0
1/2
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23/0
1/2
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24/0
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25/0
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26/0
1/2
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27/0
1/2
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28/0
1/2
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29/0
1/2
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30/0
1/2
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31/0
1/2
007
Sea coal SPEC = 15-20 kgkg / Mt of liquid Metal pouring
UTILIZATION : GSB calculation(example)
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Page 92