Technolgy Scorecard (3)

8/10/2019 Technolgy Scorecard (3)

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TYPES SUBPROCESS PHOTO DESCRIPTION

INGOT CASTING

AND

CONTINUOUS

CASTING

Continuous

casting

In continuous casting, the molten

steel in the ladle is poured into an

intermediate vessel(tundish),

released into a hollow water-cooled

copper mold, and continuously

withdrawn from the bottom of the

mold as a shell begins to form

around the molten metal.

Strip casting

Direct strip casting is a continuous

casting process for producing

metallic sheet directly from the

molten state that minimizes the

need for substantial secondary

processing.

Ingot casting

The molten steel is poured into many

cast-iron ingot mold and, when the

solidification is complete, the ingots

are taken out, reheated, and rolled

by a slabbing, blooming, or billeting

mill

Casting is a 6000 year old process. The oldest surviving casting is


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EXPANDABLE

MOLD,

PERMANENT

PATTERN

CASTING

Sand casting

Sand casting, also known as sand

molded casting, is a metal casting

process characterized by using sand

as the mold material. The term "sand

casting" can also refer to an object

produced via the sand casting

process. Sand castings are produced

in specialized factories called

foundries. Over 70% of all metal

castings are produced via a sand

casting process.

Shell mold

casting

Shell molding, also known as shell-

mold casting, is an expendable mold

casting process that uses a resin

covered sand to form the mold. Shell

mold casting is a metal casting

process similar to sand casting, in

that molten metal is poured into an

expendable mold. However, in shell

mold casting, the mold is a thin-

walled shell created from applying a

sand-resin mixture around a pattern.

The pattern, a metal piece in the

shape of the desired part, is reused

to form multiple shell molds.

Plaster mold

casting

(precision

casting)

Plaster mold casting is a

metalworking casting process similar

to sand casting except the molding

material is plaster of paris instead of

sand. Like sand casting, plaster mold

casting is an expendable mold

process, however it can only be used

with non-ferrous materials.


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Ceramic mold

casting

Ceramic mold casting, also known

ambiguously as ceramic molding, is a

group of metal casting processes that

use ceramics as the mold material. It

is a combination of plaster moldcasting and investment casting.

Vacuum casting

Vacuum mold casting, also known in

manufacturing industry as the V

process, employs a sand mold that

contains no moisture or binders. The

internal cavity of the mold holds the

shape of the casting due to forces

exerted by the pressure of a vacuum.

Vacuum molding is a casting process

that was developed in Japan around

1970.

EXPANDABLE

MOLD,

EXPENDABLE

PATTERN

CASTING

Expandable

pattern casting

(lost foam

casting)

The desired shape is created out of

foam. The shape is placed into a

container filled with sand. The metal

is poured into the risers, connected

to the foam shapes, and melts them.

The metal retains the shape of thefoam, and once it solidifies, the sand

is shaken out.

Investment

casting (lost

wax)

The desired shape is created using

wax. The wax is coated in a flurry.

Metal is poured into the flurry, and

melts the wax. Once metal solidifies,

flurry is shaken out

PERMANENT

MOLD CASTINGSlush casting

Liquid metal is poured intoa mold. It

starts solidifying near the outside of

the mold. When the desired size is

reached, the metal is poured out and

a hollow cavity remains.


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Pressure casting

A pressurized gas forces liquid metal

into a mold. The metal solidifies in

the mold, and any excess metal can

simply flow out back into the metal

basin

Die casting

Liquid metal is forced into a cavity

with a piston. The metal solidifies

quickly, and the dies open. The

product can be taken out, and the

process begins again.

Centrifugal

casting

Liquid metal is poured into a

cylindrical mold. The mold begins to

rotate, and the metal sticks to the

outside walls due to the centrifugal

forces. It solidifies and retains the

hollow shape.

Squeeze casting

Molten metal is poured into a cavity.

It doesn't fill the entire space, and a

die is extended, to change its shape.

The metal solidifies, and retains a

hollow shape, where the die used tobe.


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FINAL PRODUCT TYPES OF USED MATERIALS TEMPERATURE

Slabs, fillets and blooms.Steel, copper, alluminium,

nickel and other metals.

Slabs, fillets and blooms.Steel, copper, alluminium,


Steel, copper, alluminium,


a copper frog from 3200 BC. Casting is a manufacturing process by which a liquid m


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Sand castings can range in

size from very small to

extremely large. All but

basiclly it is used to engine

blocks and manifolds,

machine bases, gears,

pulleys.

Typical: Alloy Steel, Carbon

Steel, Cast Iron, Stainless, Steel,Aluminum, Copper,

Magnesium, Nickel

Feasible(Special order): Lead,

Tin, Titanium, Zinc.

Shell molding is an

expendable mold casting

process that uses a resin

covered sand to form themold.

Ferrous and non-ferrous

metals, cast iron, carbon steel,

alloy steel, stainless steel,

aluminum alloys, and copperalloys.

175C - 370C

Lock compnents, gears,

valces, fittings.

Only -NON FERROUS materilas

with low melting temperature -

Al, Cu, Zn, Mg.

1200C


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Used to make tooling,

especially drop forging dies,

but also injection

molding dies, die

casting dies, glass molds, st

amping dies,

and extrusion dies.

Plaster, plastic, wood, metal or

rubber.At about 1000 C.

Flywheel, Disc Case, Heat

Sink, Auto Parts,

Connecting Plate, Auto

Parts, Prototypes.

No info,probablyall metals.

Complex products.Predominantly steel and

aluminium.

Complicated, or special

items, which require high

accuracy and are produced

in very low quantity.

Almost every metal can be cast

with this method.

100-175 C to melt

the wax and pour it

out, and 550-1100 to

strengthen the

refractory mold

itself.

Ornamental products and

toys.Zinc, aluminum, tin 400C - 650C


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Steel railroad car wheels,

engine blocks.No info,probablyall metals

The casting

temperature is

about 750C.

Small and medium sized

products. Usually not

exceeding 40 kg

Zinc, aluminium, copper, tin,

lead400C - 600C

Pipes, wheels, pulleys,

nozzles.

Ferrous and non-ferrous

metals, cast iron, carbon steel,

alloy steel, stainless steel,

aluminum alloys, and copper

alloys/Typical materials that

can be cast with this process

are iron, steel, stainless steels,

glass, and alloys of aluminium,

copper and nickel.

Small items produced in

large quantities.Light alloys.


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QUANTITY QUALITY COST

Mass production.

All the products are

transformed, that way

quality is not of maximum

importance, because they

are semi finnished pieces.

High initial investment costs, cheap

labour.

Mass production

All the products are

transformed, that way

quality is not of maximum

importance, because theyare semi finnished pieces.

High initial investment costs, cheap

labour.

Mass production.

CASTING

aterial is usually poured into a mold, which contains a hollow cavity of the desired shape, and th


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Because the sand mold must

be destroyed in order to

remove the part, called the

casting, sand casting typically

has a low production rate.

Poor material strength,

high porosity possible,

poor surface finish and

tolerance. Seondary

machining often required.

Middle for equipment middle for

pattern/die low for labor.

From 5 to 50

Good surface finish and

good size tolerance reduce

the need for machining.

Surface finish 1.25 m to3.75 m.

Medium.

Low - 1-10 units/hr. Excellent Low


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Surface finishes can be

better than 2 - 4 m.Expensive.

An automated process can

create many products. Set up

cost make this

manufacturing process more

suitable to high volume

production, instead of smallbatch manufacture.

Close dimensional

accuracy, good surface

finish, and superior

mechanical properties.

Medium production costs if

automated, high equipment costs.

This casting can be used for

both special units produced

in small amounts, as well as

larger production runs.

Very high. Complex details

can be achieved, and cores

can be easily incorporated

into the foam.

High cost of machinery to operate

the casting process. Dies that speed

up the creation of large amounts of

foam patterns further increase the

prices.

Very small amounts, often

single units.

Very high. Products have

smooth surface, and all

measurements are very

accurate. Complex details

and very thin sections can

be achieved.

This is a very complicated process

that requires a lot of manual labor.

Efficient only for small quantities,

where creating automated machines

would be unnecessary or when

intricate details must be achieved.

An automated process can

create many products.

Though relatively smooth

and detailed on the

outside, it is difficult to

accurately calculate the

strength and thickness of

the product's walls.


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The high setup cost makes

pressure casting not efficientfor small runs, but an

excellent productivity rate

makes it suitable for large

batch manufacture.

Pressure casting

manufacture can be used

to produce metal castings

with superior mechanical

properties, good surface

finish, and close

dimensional accuracy.

Medium production costs, medium

equipment costs

Very high. Can produce a lot

of copies in a very short

time.

The final product has

smooth surfaces, and can

have accurate details.

The machinery required to begin the

casting process is very expensive, but

production of individual units is very

cheap and efficient.

True centrifugal casting is a

manufacturing process that

is capable of very high rates

of productivity.

Mechanical properties of

centrifugal castings are

excellent. Quality castings

with good dimensional

accuracy can be produced

with this process.

Low equipment cost, low labour cost.

Multiple pieces produced

quickly in highly automated

processes.

Smooth and accurate

surface, no flash is created

so requires little

machining.

High cost of machinery. Calculations

and equipment need to be very

accurate which increases prices.

Little waste material.


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TIME SIZE/WEIGHT SHAPE DEFECTS

Days.From small sizes to

big sizes.

Days.From small sizes to

big sizes.

Used mainly in big

and heavy pieces.

n allowed to solidify.The solidified part is also known as a casting, which is ejected or broken o


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Takes a lot of time to

produce multiple parts.

Casted parts can

vary greatly in sizeand weight, ranging

from a couple

kilogramms to

several tons.

Typical: Thin-walled,

Complex Solid,

Cylindrical Solid, Cubic

Solid, Complex. Feasible:

Flat Thin-walled,

Cylindrical Thin-walled,

Cubic

Setup and production

of shell mold patterns

takes weeks.

Size limits of 30 g

to 90 kg depending

on material.

Minimum

thicknesses can beas low as 1.5 mm

to 6.25 mm.

Possibility of cracking,

porosity.


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Very short lead time. From 60 g to a ton.

A fully automated

machine can cast a lot

of products in a short

amount of time.

Usually used for

small parts.

In vacuum casting

almost all shapes of final

product are possible.

Very low possibility of

gas porosity.

Depending on the

complexity of the foam

pattern. When dies are

not used, it can take a

long time to machine

the pattern to achieve

the expected results.

There is virtually no

maximum limit, but

the products

usually weigh more

than 0.5 kg.

The manufacturing

process is very long,

taking many hours for a

single part to be cast.

Usually limited to

small parts, though

objects as heavy as

40 kg can be cast.

Very quick production

of goods

Objects can be

relatively large,

however they are

hollow, and light.

Inaccurate interior

measurements.


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Time, required to setup

the machine, makingthis type of casting

relatively slow. Process

itself has medium

speed.

Usually used for

small parts (usually

max 70-80kg).

Very complicated

casting geometry is

limited.

Gas trapped in themetal as well as

oxidation effects are

greatly reduced.

A fully automated

machine can cast a lot

of products in a very

short amount of time.

Usually not

exceeding 40 kg

Cold shuts, misruns,

inclusions.

Take long time to

prepare equipment.

Fast production of

goods.

Castings can be

made in almost any

length, thickness

and diameter.

Mechanical properties

of centrifugal castings

are excellent. Wall

thickness range from 2.5

mm to 125 mm.

Resistant to

atmospheric corrosion,

a typical situation with

pipes.

Automated process

cannot produce

very large objects.

Low levels of porosity.


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Can produce very large parts,

Can form complex shapes, Manymaterial options, Low tooling

and equipment cost, Scrap can

be recycled, Short lead time

possible.

Poor material strength: High

porosity possible: Poorsurface finish and tolerance:

Seondary machining often

required: Low production

rate: High labor cost.

Mass production, good

dimensional accuracy and

surface finish.

Part size limited, expensive

patterns and equipment

required.


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Can eliminate secondary

machining operations, good

tolerances and can be held to

0.4 %. Can make thin cross

sections.

Castings with thin walled

sections may be manufactured

using this technique. Gas related

defects are reduced. This

manufacturing process can

produce metal castings with

close dimensional accuracy,good surface finish, and superior

mechanical properties.

Requires setup time, requires

a vacuum pump.

Very accurate. Can easily

incorporate cores into the

design. The finished product

requires little to no machining.

No flashes are formed. Theprocess can be automated.

As machines required for the

process are expensive, there

is a large starting cost.

Patterns made of foam can be

easily damaged and producefaulty parts.

Very accurate. Machines are

cheaper than ones required for

die casting and can achieve more

details. Most metals can be cast

using this technique.

A very complicated and

expensive process, which

requires a lot of complex

machinery. The casting

process takes a very long

time.

Process save a lot of material.

Produces lightweight parts.

Fairly accurate outside details.

Produces goods quickly. Doesn't

require expensive machinery.

Cannot produce accurate

details on the inside of the

structure. Difficult to predict

the strength and mechanical

properties of finished project


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An advantage of low-pressure

casting lies in the reduction of

returns. With low pressure

casting, one can count on

considerably lower costs forcleaning, rework, and re-melting

of returns. Pressure casting

manufacture can be used to

produce metal castings with

superior mechanical properties,

good surface finish, and close

dimensional accuracy.

Requires setup time

Low manufacturing cost of

individual units. Very accurate

and smooth details. Fast

production of units.

High cost of casting machines.

Casting of large products

difficult.

Can form very large parts, good

mechanical properties, good

surface finish and accuracy, low

equipment cost, low labour cost,

little scrap generated.

Limited to cylindrical parts,

secondary machining is often

required for inner diameter,

long lead time possible.

Accurate, requires little

machining, doesn't waste

material.

Requires high costs of

machinery, needs to be very

accurate as there is no flash

for safety, tools are very

unique and can only produceone part.

Technolgy Scorecard (3)

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