presentation conference opatija 2011 ml2

8/2/2019 Presentation Conference Opatija 2011 Ml2

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Opatija, April 28th 29th, 2011 Ductile iron cored wire process O. BAHUON 1

Technical overview of Cored WireTechnical overview of Cored Wire

for Ductile Iron treatmentfor Ductile Iron treatment

ElFiCastElFiCast

Cored wire for iron foundriesCored wire for iron foundries

11th International foundrymenconference

Croatia, Opatija, April 28 29, 2011


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Brief history of Cored Wire processBrief history of Cored Wire process

The cored wire was introduced in the 1980s, first in the steelindustry, as a simple and economical way to introduce anyelement of addition or treatment in deep ladles of liquid metal.

The advantage of this method was quickly understood andapplications for the treatment of ductile iron was developed.

Several types of applications exist today in the elaboration of

ductile iron, cored wire can be used for desulfurization, for thetreatment of spheroidization, for inoculation in ladle or even

just before pouring, and some others applications linked tospecific requirements.


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Focus on theFocus on the

Nodularization of the ductile iron graphiteNodularization of the ductile iron graphite

Difficulties

=> Introduce the magnesium (boiling

temperature at 1090 C) in liquidiron at 1450 C

=> Limited sobubility of magnesium inthe liquid iron


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Metallurgical High Consistency

No Risk of Human Error

Cost Automation

High Productivity

Health & Safety Safe Use of Hazardous material Storage Clean & Easy Handling

Material Identified

Lower Dispersion Injection parameters adjusted

after the filling of the ladle

Reduction of Mg Targeted high metal quality

AdvantagesAdvantages ofofCoredCored WireWire processprocess


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Savings using Cored WireSavings using Cored Wire

SAVINGS

Unknow parameters(weigth)

Scattering

Cored Wire addition% min

Aim Using Lumps

Aim Using CW


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ComponentsComponents

of the Cored Wire treatment processof the Cored Wire treatment process

1) Consumable => wire + addition process

2) Equipment => Ladle + feedings equipment3) Liquid Iron

To highlight the benefits of Cored Wire process weneed to apply the best practices on these

components


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What do we need for to produceWhat do we need for to producean effective and efficient cored wire ?an effective and efficient cored wire ?

Choice and control of raw materials

Chemistry, sizing, flowability, ISO certified suppliers Homogeneous and consistent powder metric weight

weighting and blending in-situ

Automatic control of each individual powder feeding

& weighting system

Mixing just before filling the wire

Speed control of the profiling line

Prevention of lock seam opening hazards

Optimized final packaging

Full traceability

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Keys successKeys successto produce a consistent cored wireto produce a consistent cored wire

Homogeneity of encapsulated powder (blends)

The homogeneity of the composition of the encapsulatedpowder is guarantied by in-situ weighting and lateblending of the single components

Avoid to use pre-mix batches

Consistent filling rate The consistency of the weight of encapsulated powder

(grams of powder per meter of wire) all along the wire isobtained by using a permanent servo-controlled weightingsystem during filling

Avoid to fill the wire at constant volume

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Ferrostatic

Pressure

- Memory of coiling

- Flattening between feeder rolls

- high distance between guide tube and ladle

- low penetration into the liquid bath (twisting)

- Release of Mg on the top of the ladle => poor

efficiency nonnon--steady yieldssteady yields

FeedingFeeding equipmentequipment2


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FeedingFeeding equipmentequipment2

Cored WireCored WireInjectionInjectionPracticesPractices


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Straight and vertical injectionStraight and vertical injection

Straighten the wire to avoid residual constraint

Specific feeding equipment with adapted rolls

Guiding tube perpendicular to the bath (vertical)

Shorter distance between guiding tube and bath

No effect of ferrostatic pressure

Deeper penetration of wire into the melt

Deeper release of the product and longerreaction time with the molten metal

High and steadyHigh and steady yieldsyieldsDeep

penetration

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WireWire straighteningstraightening

Non-straightened wire Straightened wire

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GeometryGeometry of theof the treatmenttreatment ladleladle2

A ratio of H/D = 2 minimum is recommended in order to

have the highest metallo-static charge to oppose the

magnesium vapor pressure.

Also the height of the free board above the liquid surface

in the ladle before treatment, must be compatible with the

violence of the reaction.

H/D is the critical factor for the yield ofmagnesium, with the same cored wire we

can see a double consumption of wire withbad ratio


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WireWire diameterdiameter linklink to theto the ladleladle

Determinated by Mg content in the powder, requestedaddition of Mg, and speed of injection.

Economy is also a factor, typically higher diameter lead to lowprice. The goal is to find a wire whose ratio is: weight ofpowder/weight of wire is as high as possible.

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TemperatureTemperature ofofliquidliquid ironiron

This is the most important factor since temperature dictates

the vapor pressure of Magnesium (8 bars at 1400C, 17 barsat 1500C)

Consequently the speed of the Mg vaporization increases. Inaddition, the instantaneous flow rate of Mg is affected by the

injection speed (for a given Mg % in the powder)A greater Mg flow rate associated with liquid iron temperatureabove 1500C result in poor yields due to a formati on of biggerbubbles of Mg vapor.

And dont forget that solubility of Mg in cast iron decreases withtemperature.

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FactorsFactors toto bebe consideredconsidered whenwhen treatingtreating castcast ironiron

Liquid iron treatment temperature

Magnesium rate (for Mg treatment) Liquid iron weight

Liquid iron characteristics (oxidation, % S)

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Today we can achieve up to 60 % magnesiumrecovery with a pure magnesium patented cored

wire and consistent process


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Insulation which delays the heat transfer,

thus protects the Magnesium (~1 second)

deeper penetration of Mg into the liquidsteel. reduces the heat from thermalradiation. optimizes the wire guiding

Dramatic Improvement in Mg RecoveryDramatic Improvement in Mg Recovery

Very Steady ResultsVery Steady Results

Highly Predictable ResultsHighly Predictable Results

PAPMAGPAPMAGTechnologyTechnology

Deep

penet

ration

Externalsteel

sheath

Internalsteel

sheath

Insulation

Powder


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Pioneer, Leader, AFFIVAL is yourinnovative and sustainable partner.

Thank you for your attention


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Wire Feeding in FoundryWire Feeding in Foundry


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Wire Feeder for foundriesWire Feeder for foundries

Speed injection range: 0 to 120 m/min

Very accurate and steady injection speed (cm/min)

Very accurate length of wire fed (mm)

Light equipment easy to locate (ladle, mould ) Customizable equipment for any customer requirement


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Treatment booth for foundryTreatment booth for foundry


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Treatment BoothTreatment Booth

Wire feeder

Entry guides Exit guide tubes

Movable ladle cover

Sliding Door

De-dusting systemcompatible (not provided)

Possible full automation

All treatment Nodularization Inoculation


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Treatment booth for foundryTreatment booth for foundry

presentation conference opatija 2011 ml2

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