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Ver. 4/14/09 1
Casting C87850
Larry MullerManager, Metallurgy and Technical Services
Chase Brass & Copper Co., LLCMontpelier, OH
Ver. 4/14/09 2
C87850 Water Meter Bodies
Major Elements Rem.
Zn(%)
0.05 – 0.20
P(%)
2.7 – 3.4
Si(%)
74.0 – 78.0
Cu(%)
C87850 Chemical Requirements
0.10
Sb(%)Residual
Elements 0.20
Ni(%)
0.10
Fe(%)
0.500.100.300.09
TOEMn(%)
Sn(%)
Pb(%)
Ver. 4/14/09 3
16161680
1810 1840 1842 1850 1877
14001500
1600170018001900
Alloy
Liquidus Temperatures (F)
ECO BRASS C87500 C92200 C84400C89520 C83600 C89833
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45
170
280 291 292 305353
0
100
200
300
400
Alloy
Freezing Ranges (F)
ECO BRASS C87500 C83600 C84400C92200 C89833 C89520
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Sand Cast Water Meter Bodies
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• Foundry: Tohoku, Fukushima Japan
• Original alloy: C83600
• Current alloy: C87850
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Background
• Reason for alloy change: Pb leachate reduction from 5 ppm ►1ppm
• Year alloy changed: 2000
• Current total production: Over 9 million
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Melting
• Charge materials: Run-around scrap, ingot, turnings
• Melting furnace: High frequency crucible
• Dross generation: Less than C83600
• Fume generation: Less than yellow brass
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Pattern Design
• Pattern shrinkage: 1.2% to 1.7%
• Pattern draft: 0.5º
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Gating & Risering
• Gating ratio: 1: 2-3: 3-6
• Sprue diameter: 0.6” – 1.2”
• Casting weight: 13mm - 1.47 lb
20mm – 2.74 lb
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Molding Sand
• Sand type: No. 90-100 AFS Olivene
• Binder type: No-bake, 8.4%
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Casting Parameters
• Liquidus temperature: 1616º F
• Melt temperature: 2100º F
• Pour start temp.: 1830 - 1960º F
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Gating & Risering
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Gating & Risering
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Shakeout Parameters
• Critical temperature: Controlled for C836
• Shakeout precautions: None
• Gate & riser removal: Cut-off
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Machining
• % Machinability: 90%-105% of C836
• Coolant: Machined dry
• Tooling type: Cutting – carbide
Drilling – carbide, HSS
• Tool life: 70%
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Microstructure
C87850 C83600
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C87850 ASTM B208 Tensile Strength Results
Tensile Strength ksi
frequ
ency
58 60 62 64 66 68(X 1000.0)
0
2
4
6
8
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C87850 ASTM B208 Yield Strength Results
Yield Strength ksi
frequ
ency
22 24 26 28 30 32(X 1000.0)
0
2
4
6
8
10
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C87850 ASTM B208 Elongation Results
Elongation %
frequ
ency
15 19 23 27 31 350
2
4
6
8
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C87850 ASTM B208 Brinell Hardness Results
Brinell Hardness 500kg
frequ
ency
99 103 107 111 115 119 1230
2
4
6
8
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Summary of Sand Casting Parameters for C87850
• Gating system: Non-pressurized or pressurized; suggest gating like silicon bronze
Tapered sprue or reverse taper + choke
Spread ingates out to prevent hot spots
• Pouring temperature: Keep it low (melting T = 1615F; suggest 1950F maximum)
• Risers: Use sufficient riser necks if risers are necessary at all
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Corrosion Resistance
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Corrosion depth after ISO6509
dezincification test(12.7 g/l CuCl2.2H2O for
24 hrs. at 167F).
Maximum corrosion depth of C360 and C377 = 0.04" (1.0mm) while ECO BRASS is almost zero.
ECO BRASS C36000
Phosphorus and lower zinc levels in ECO BRASS give it superior dezincification resistance.
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Comparison of ISO 6509 test results shows ECO BRASS excellent dezincification resistance.
170
120
20 20 15
5
100
70
0.1 0.1 0.1 0.1
0
20
40
60
80
100
120
140
160
180
Maximum Average
ECO BRASS w/o P C87500 ECO BRASS Rod
ECO BRASS Forging ECO BRASS Casting C83600
Cross-hatched bars indicates dezincification occurred. Solid bars indicate there was general corrosion only.
Cor
rosi
on D
epth
(μm
) 170 μm = 0.0067”
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ECO BRASS dezincification resistance data shown in the Turner Diagram
Transition boundary for C353304
Results for ECO BRASS
Transition boundary for C3853
Layer-type dezincification2
Plug-type dezincification1
Key to the Graph
1
2
3
4
Calcium Carbonate (mmol/L)
Res
idua
l Chl
orid
e (m
l/L)
Ver. 4/14/09 28
Maximum corrosion depth of ECO BRASS® in various above and below ground environments.
0
20
40
60
Maximum Dezincification Depths (microns)
ISO6509 Air - 9 Mo., 3.5pH Clay Soil - 9 Mo., 3.5pHSandy Soil - 9 Mo., 3.5pH 5 Months - Underground (Osaka) 12 Months - Still Water12 Months - Agitated Water
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Water meter body performance in Japan shows comparable behavior with C836 and bismuth brass. 13mm and 20mm refer to water meter orifice size.
100
45
80
100
220
50
0
20
40
60
80
100
120
140
Max
imum
Dez
inci
ficat
ion
Dep
th(m
icro
ns)
3.8 Yr.(13mm)
5.2 Yr.(20mm)
7 Yr.(20mm)
8 Yr.(13mm)
C83600 ECO BRASS CAC 902
4.0-6.00.30 max4.3-6.0Tin
1.0-2.5--Bismuth
0.25 max0.09 max4.0-5.7Lead
84.5-90.074.0-78.084.0-86.0Copper
4.0-8.0Rem.4.3-6.0Zinc
-0.05-0.20-Phos.
-2.7-3.4-Silicon
CAC902ECO BRASSC83600
48020mm
44313mm
CAC902ECO BRASSC83600#
Measured
Ver. 4/14/09 3009M-0408
290
4 4
050
100150200250300
Hou
rs to
App
eara
nce
of
Cra
cks
ECO BRASS C360 Hex Rod C377 Hex Rod
Results of Stress Corrosion Cracking Tests
ECO BRASS C360 Hex Rod C377 Hex Rod
No cracks
ASTM G37NH4SO4 + CuSO4-5H2O + NH4OH 68F, 1500 kgf torque
Silicon, low zinc, high strength levels give ECO BRASS high stress corrosion cracking resistance.
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Permanent Mold Cast Water Meters
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• 13mm: High Pressure Die Cast
• 13mm production: 500,000
• 20mm: Low Pressure Permanent Mold
• 20mm production: 50,000
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Equipment
Mold
Spout
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Equipment
C17510 Mold Interior Pour Spout
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Sand Core• Silica sand with phenolic resin binder
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Casting Parameters
1571Solidus
1616Liquidus
Temperatures (F)
1830Casting
250Mold