1

PREFACE

This project report has been prepared in fulfilment of industrial training to be

carried out in third year of our four year B. TECH course. For preparing the

project report, we have visited This project Report has been prepared in

fulfilment of industrial training to be carried out in Baldevnagar casting industry

under Bhagwan Dass Jagan Nath Casting during the suggested duration for the

period of 28 days, to avail the necessary information. The blend of learning and

knowledge acquired during our practical studies at the company is presented in

this report.

The reasons behind visiting the casting industry and preparing the project report

is to study the mechanical overview, machinery overview cycle and process of

casting and details of control and instrumentation required in casting company.

We have carried out this training under well experienced and highly qualified

engineers of BDJN of department viz. Mechanical, chemical and control and

instrumentation depts. We have taken the opportunity to explore the Mechanical

department, necessity of Casting Industry. We have tried our best to cover all

the aspects of the Casting Company and their brief detailing in the project

report.

All the above mentioned topics will be presented in the following pages of this

report. The main aim to carry out this training is to familiarize ourselves with

the real industrial scenario, so that we can rotate with our engineering studies.

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INDEX

Page No

1. Introduction of casting 3

2. Sand testing 5

A. Moisture content testing 5

B. Clay content testing 6

C. Grain fitness test 7

D. Permeability test 8

E. Strength test 9

F. Mould hardness test 11

3. Moulding machine 12

4. Types of casting 13

5. Terminology 18

6. Pattern 19

A. Single piece pattern 19

B. Split pattern or two piece pattern 19

C. Gated pattern 20

D. Cope and drag pattern 20

E. Match plate pattern 20

F. Followed board pattern 20

7. Cores 22

8. Core shooter machine 24

9. Furnace 27

10. Pouring 31

11. Shakeout machine 33

12. Material separation 34

13. Shot blasting machine 35

14. Defects 36

15. Testing of material 40

16. Conclusion 42

17. Bibliography 43

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INTRODUCTION

CASTING:-

Casting is one of the earliest metal-shaping method known to human beings. It generally

means pouring molten metal into a refractory mould with cavity of the shape to be made, and

allowing it to solidify. When solidified, the desired metal objects is taken out from the

refractory mould either by breaking the mould or by taking the apart. The solidified object is

called casting. This process is called 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.

Sand casting is relatively cheap and sufficiently refractory even for steel foundry use. In

addition to the sand, a suitable bonding agent (usually clay) is mixed or occurs with the sand.

The mixture is moistened, typically with water, but sometimes with other substances, to

develop strength and plasticity of the clay and to make the aggregate suitable for molding.

The sand is typically contained in a system of frames or mold boxes known as a flask.

The mold cavities and gate system are created by compacting the sand around models,

or patterns, or carved directly into the sand.

Sand casting is one of the most popular and simplest types of casting, and has been used for

centuries. Sand casting allows for smaller batches than permanent mold casting and at a very

reasonable cost. Not only does this method allow manufacturers to create products at a low

cost, but there are other benefits to sand casting, such as very small-size operations. From

castings that fit in the palm of your hand to train beds (one casting can create the entire bed

for one rail car), it can all be done with sand casting. Sand casting also allows most metals to

be cast depending on the type of sand used for the molds.

Sand casting requires a lead time of days, or even weeks sometimes, for production at high

output rates (1–20 pieces/hr.-mold) and is unsurpassed for large-part production. Green

(moist) sand has almost no part weight limit, whereas dry sand has a practical part mass limit

of 2,300–2,700 kg (5,100–6,000 lb.). Minimum part weight ranges from 0.075–0.1 kg (0.17–

0.22 lb.). The sand is bonded together using clays, chemical binders, or polymerized oils

(such as motor oil). Sand can be recycled many times in most operations and requires little

maintenance.

BASIC PROCESS:-

There are six steps in this process:

1. Place a pattern in sand to create a mold.

2. Incorporate the pattern and sand in a gating system.

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3. Remove the pattern.

4. Fill the mold cavity with molten metal.

5. Allow the metal to cool.

6. Break away the sand mold and remove the casting.

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SAND TESTING

The moulding sand after it is prepared should be properly tested to see that require properties

are achieved. Tests are conducted on a sample of the standard sand. The moulding sand

should be prepared exactly as it is done in the shop on the standard equipment and then

carefully enclosed in a container to safeguard its moisture content.

Sand tests indicate the moulding sand performance and help the foundry men in controlling

the properties of moulding sands. Sand testing controls the moulding sand properties through

the control of its composition.

The following are the various types of sand control tests:

1. Moisture content test

2. Clay content test

3. Grain fitness test

4. Permeability test

5. Strength test

6. Mould hardness test

Moisture content test:

Moisture is the property of the moulding sand it is defined as the amount of water present in

the moulding sand. Low moisture content in the moulding sand does not develop strength

properties. High moisture content decreases permeability.

Procedures are:

1. 20 to 50 gms of prepared sand is placed in the pan and is heated by an infrared heater bulb

for 2 to 3 minutes.

2. The moisture in the moulding sand is thus evaporated.

3. Moulding sand is taken out of the pan and reweighed.

4. The percentage of moisture can be calculated from the difference in the weights, of the

original moist and the consequently dried sand samples.

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Percentage of moisture content = (W1-W2)/(W1) %

Where,

W1- Weight of the sand before drying,

W2- Weight of the sand after drying.

Clay content test:

Clay influences strength, permeability and other moulding properties. It is responsible for

bonding sand particles together.

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Procedures are:

1. Small quantity of prepared moulding sand was dried

2. Separate 50gms of dry moulding sand and transfer wash bottle.

3. Add 475cc of distilled water + 25cc of a 3%NaOH.

4. Agitate this mixture about 10 minutes with the help of sand stirrer.

5. Fill the wash bottle with water up to the marker.

6. After the sand etc., has settled for about 10 minutes, Siphon out the water from the wash

bottle.

7. Dry the settled down sand.

8. The clay content can be determined from the difference in weights of the initial and final

sand samples.

Percentage of clay content = (W1-W2)/(W1) * 100

Where, W1-Weight of the sand before drying,

W2- Weight of the sand after drying.

Grain fitness test:

The grain size, distribution, grain fitness are determined with the help of the fitness testing of

moulding sands. The apparatus consists of a number of standard sieves mounted one above

the other, on a power driven shaker.

The shaker vibrates the sieves and the sand placed on the top sieve gets screened and collects

on different sieves depending upon the various sizes of grains present in the moulding sand.

The top sieve is coarsest and the bottom-most sieve is the finest of all the sieves. In between

sieve are placed in order of fineness from top to bottom.

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Procedures are:

1. Sample of dry sand (clay removed sand) placed in the upper sieve

2. Sand is vibrated for definite period

3. The amount of same retained on each sieve is weighted.

4. Percentage distribution of grain is computed.

Permeability test:

The quantity of air that will pass through a standard specimen of the sand at a particular

pressure condition is called the permeability of the sand.

Following are the major parts of the permeability test equipment:

1. An inverted bell jar, which floats in a water.

2. Specimen tube, for the purpose of hold the equipment

3. A manometer (measure the air pressure)

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Procedures are:

1. The air (2000cc volume) held in the bell jar is forced to pass through the sand specimen.

2. At this time air entering the specimen equal to the air escaped through the specimen

3. Take the pressure reading in the manometer.

4. Note the time required for 2000cc of air to pass the sand

5. Calculate the permeability number

6. Permeability number (N) = ((V x H) / (A x P x T))

Where,

V-Volume of air (cc)

H-Height of the specimen (mm)

A-Area of the specimen (mm2)

P-Air pressure (gm / cm2)

T-Time taken by the air to pass through the sand (seconds)

Strength test:

Measurements of strength of moulding sands can be carried out on the universal sand strength

testing machine. The strength can be measured in compression, shear and tension.

The sands that could be tested are green sand, dry sand or core sand. The compression and

shear test involve the standard cylindrical specimen that was used for the permeability test.

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a. Green compression strength:

Green compression strength or simply green strength generally refers to the stress required to

rupture the sand specimen under compressive loading. The sand specimen is taken out of the

specimen tube and is immediately (any delay causes the drying of the sample which increases

the strength) put on the strength testing machine and the force required to cause the

compression failure is determined. The green strength of sands is generally in the range of 30

to 160 KPa.

b. Green shear strength:

With a sand sample similar to the above test, a different adapter is fitted in the universal

machine so that the loading now be made for the shearing of the sand sample. The stress

required to shear the specimen along the axis is then represented as the green shear strength.

It may vary from 10 to 50 KPa.

c. Dry strength:

This test uses the standard specimens dried between 105 and 1100 C for 2 hours. Since the

strength increases with drying, it may be necessary to apply larger stresses than the previous

tests. The range of dry compression strengths found in moulding sands is from 140 to 1800

KPa, depending on the sand sample.

Procedures are:

1. Specimen is held between the grips

2. Apply the hydraulic pressure by rotating the hand wheel

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3. Taking the deformation use of the indicators.

Mould hardness test:

Hardness of the mould surface can be tested with the help of an “indentation hardness tester”.

It consists of indicator, spring loaded spherical indenter.

The spherical indenter is penetrates into the mould surface at the time of testing. The depth of

penetration w.r.t. the flat reference surface of the tester.

Mould hardness number = ((P) / (D – (D2-d

2))

Where,

P- Applied Force (N)

D- Diameter of the indenter (mm)

d- Diameter of the indentation (mm)

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MOLDING MACHINE

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TYPES OF CASTING

EXPENDABLE MOLD CASTING: -Expendable mold casting is a generic

classification that includes sand, plastic, shell, plaster, and investment (lost-wax technique)

moldings. This method of mold casting involves the use of temporary, non-reusable molds.

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SAND CASTING STEPS

PLASTER MOLD CASTING:-

Plaster casting is similar to sand casting except that plaster of Paris is substituted for sand as

a mold material. Generally, the form takes less than a week to prepare, after which a

production rate of 1–10 units/hr. mold is achieved, with items as massive as 45 kg and as

small as 30 g with very good surface finish and close tolerances. Plaster casting is an

inexpensive alternative to other molding processes for complex parts due to the low cost of

the plaster and its ability to produce near net shape castings. The biggest disadvantage is that

it can only be used with low melting point non-ferrous materials, such as aluminium, copper,

magnesium, and zinc.

NON-EXPENDABLE MOLD CASTING:-

Non-expendable mold casting differs from expendable processes in that the mold need not be

reformed after each production cycle. This technique includes at least four different methods:

permanent, die, centrifugal, and continuous casting. This form of casting also results in

improved repeatability in parts produced and delivers Near Net Shape results.

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PERMANENT MOLD CASTING:-

Permanent mold casting is a metal casting process that employs reusable molds ("permanent

molds"), usually made from metal. The most common process uses gravity to fill the mold.

However, gas pressure or a vacuum are also used. A variation on the typical gravity casting

process, called slush casting, produces hollow castings. Common casting metals

are aluminum, magnesium, and copper alloys. Other materials include tin, zinc,

and lead alloys and iron and steel are also cast in graphite molds. Permanent molds, while

lasting more than one casting still have a limited life before wearing out.

DIE CASTING: - The die casting process forces molten metal under high pressure into mold

cavities (which are machined into dies). Most die castings are made from nonferrous metals,

specifically zinc, copper, and aluminium-based alloys, but ferrous metal die castings are

possible. The die casting method is especially suited for applications where many small to

medium-sized parts are needed with good detail, a fine surface quality and dimensional

consistency.

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CONTINUOUS CASTING: - Continuous casting is a refinement of the casting

process for the continuous, high-volume production of metal sections with a constant cross-

section. Molten metal is poured into an open-ended, water-cooled mold, which allows a 'skin'

of solid metal to form over the still-liquid Centre, gradually solidifying the metal from the

outside in. After solidification, the strand, as it is sometimes called, is continuously

withdrawn from the mold. Predetermined lengths of the strand can be cut off by either

mechanical shears or traveling oxyacetylene torches and transferred to further forming

processes, or to a stockpile. Cast sizes can range from strip (a few millimeters thick by about

five meters wide) to billets (90 to 160 mm square) to slabs (1.25 m wide by 230 mm thick).

Sometimes, the strand may undergo an initial hot rolling process before being cut.

Continuous casting is used due to the lower costs associated with continuous production of a

standard product, and also increased quality of the final product. Metals such as steel, copper,

aluminum and lead are continuously cast, with steel being the metal with the greatest

tonnages cast using this method.

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TERMINOLOGY

Metal casting processes uses the following terminology:-

DRAG: - The bottom half of the pattern, flask, mold, or core.

COP: - The top half of the pattern, flask, mold, or core.

RISER: - An extra void in the mold that fills with molten material to compensate for

shrinkage during solidification.

PARTING LINE: - This is the dividing line between the two molding flask that makes

up the sand mould. In split pattern it is also the diving line between two halves of the pattern.

SPRUE: - The pouring cup attaches to the sprue, which is the vertical part of the gating

system. The other end of the sprue attaches to the runners.

RUNNER: - The horizontal portion of the gating system that connects the sprues to the

gates.

MOLD CAVITY: - The combined open area of the molding material and core, where the

metal is poured to produce the casting.

CORE: - An insert in the mold that produces internal features in the casting, such as holes.

Core print: The region added to the pattern, core, or mold used to locate and support

the core.

POURING BASIN: -

A small funnel- shaped cavity at the top of the mould into which the molten metal is poured.

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PATTERN

An approximate duplicate of the final casting used to form the mold cavity.

PATTERN MATERIAL:

The usual pattern materials are wood, metal and plastics. The most commonly used pattern

material is wood, the main reason being the easy availability and low weight. Also, it can be

easily shaped and is relatively cheap. But the main disadvantage of wood is its absorption of

moisture as result of which distortions and dimensional changes occur. A good construction

may be able to reduce the warpage to some extent. Hence, proper seasoning and upkeep of

wood is almost a pre-requisite for large-scale use of wood as a pattern material.

The usual varieties wood commonly used for making patterns are pine, mahogany, teak,

walnut and deodar. Besides the wood, the polywood boards of the veneer type as well as the

particle boards are also used for making patterns.

SINGLE PIECE PATTERN: -

These are inexpensive and the simplest type

of pattern. As the name indicates,

They are made of a single piece. This

type of pattern used in case where the

job is very simple and does not create

Any withdrawal problems. It is also used

for applications in very small-scale

production or in prototype development.

SPLIT PATTERN OR TWO PIECE PATTERN: -

This is the most widely used type of pattern

for intricate castings. When the

contour of casting makes its withdrawal

from the mould difficult, or when the

depth of the casting is too high, then the

pattern is split into two parts so that one

part is in the drag and the other in the cope.

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GATED PATTERN: -

This is an improvement over the simple pattern where the gating and runner system are

integral with the pattern.

This would eliminate the hand cutting of

The runner and gates and help in improving

The productivity of the moulder.

COPE AND DRAG PATTERN: -

These are similar to split patterns. In addition to splitting the pattern, the cope and drag

halves of the

pattern along with the gating and risering

system are attached separately to the metal

or wooden plate along with the alignment

pins. They are called the cope and drag

pattern. These types of patterns are used

for castings which are heavy and

inconvenient for handling as also for

continuous production.

MATCH PLATE PATTERN: -

These are extensions of the previous type. Here, the cope and drag pattern the risering are

mounted on a single matching metal or wooden plate on either side. On one side of the match

plate or cope flask is prepared and on the other, the drag flask. After moulding when the

match plate is removed, a complete mould with gating is obtained by joining the cope and the

drag together.

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FOLLOWED BOARD PATTERN: -

This type of pattern is adopted for those casting where there are some portions, which are

structurally weak and if not supported properly are like to break under the force of ramming.

Hence, The bottom board is modified as a follow

Board to closely fit the contour of the weak pattern

And thus support it during the ramming of the drag.

During the preparation of the cope, no follow board

Is necessary because the sand that is already compacted

In the drag will support the fragile pattern.

PATTERN USED IN INDUSTRY

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CORES

Cores are used to make holes, recesses etc. in castings

So where coring is required, provision should be made to support the core inside the mould

cavity. Core prints are used to serve this purpose. The core print is an added projection on the

pattern and it forms a seat in the mould on which the sand core rests during pouring of the

mould.

The core print must be of adequate size and shape so that it can support the weight of the core

during the casting operation.

To produce cavities within the casting such as for liquid cooling in engine blocks

and cylinder heads negative forms are used to produce cores. Usually sand-molded, cores are

inserted into the casting box after removal of the pattern. Whenever possible, designs are

made that avoid the use of cores, due to the additional set-up time and thus greater cost.

With a completed mold at the appropriate moisture content, the box containing the sand mold

is then positioned for filling with molten metal

typically iron, steel, bronze, brass, aluminium, magnesium alloys, or various pot metal alloys,

which often include lead, tin, and zinc. After filling with liquid metal the box is set aside until

the metal is sufficiently cool to be strong. The sand is then removed revealing a rough casting

that, in the case of iron or steel, may still be glowing red. When casting with metals like iron

or lead, which are significantly heavier than the casting sand, the casting flask is often

covered with a heavy plate to prevent a problem known as floating the mold. Floating the

mold occurs when the pressure of the metal pushes the sand above the mold cavity out of

shape, causing the casting to fail.

Left: Corebox, with resulting (wire reinforced) cores directly below. Right:- Pattern (used

with the core) and the resulting casting below (the wires are from the remains of the core)

After casting, the cores are broken up by rods or shot and removed from the casting. The

metal from the sprue and risers is cut from the rough casting. Various heat treatments may be

applied to relieve stresses from the initial cooling and to add hardness—in the case of steel or

iron, by quenching in water or oil. The casting may be further strengthened by surface

23

compression treatment—like shot peening—that adds resistance to tensile cracking and

smooths the rough surface.

DESIGN REQUIRMENT:

The part to be made and its pattern must be designed to accommodate each stage of the

process, as it must be possible to remove the pattern without disturbing the molding sand and

to have proper locations to receive and position the cores. A slight taper, known as draft,

must be used on surfaces perpendicular to the parting line, in order to be able to remove the

pattern from the mold. This requirement also applies to cores, as they must be removed from

the core box in which they are formed. The sprue and risers must be arranged to allow a

proper flow of metal and gasses within the mold in order to avoid an incomplete casting.

Should a piece of core or mold become dislodged it may be embedded in the final casting,

forming asand pit, which may render the casting unusable. Gas pockets can cause internal

voids. These may be immediately visible or may only be revealed after extensive machining

has been performed. For critical applications, or where the cost of wasted effort is a factor,

non-destructive testing methods may be applied before further work is performed.

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CORE SHOOTER MACHINE

FULLY AUTOMATIC

All the operations have timer, and hence each operations can be set as per required time and

the machine operates as per the time settings, sand feeding to sand shooting tank is also

automatic.

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SALIENT FEATURES

Proven sturdy and job rated equipment.

Heavy-duty bars for core box carriage plates.

Pneumatic clamping system for two halves of core.

Built in control system to facilitate various operation

Facility of auto repeat cycle operation.

Auto/Manual mode selection facility

Safety interlocks incorporated in the control system.

Air blow gun for cleaning purpose.

All movements by means of pneumatic cylinders.

Operation:-

1. Fully automatic machine.

2. It’s temperature 310 to 250.

3. Time take in make core approximate 90-100 seconds.

4. Time take reduce die at least 8-10 sec.

5. At a time make only two core.

CORE PIECE

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27

FURNACE

An electric arc furnace (EAF) is a furnace that heats charged material by means of

an electric arc.

Industrial arc furnaces range in size from small units of approximately one ton capacity (used

in foundries for producing cast iron products) up to about 400 ton units used for

secondary steelmaking.

TEMPERATURE RANGE:-Arc furnaces used in research laboratories and bydentists may

have a capacity of only a few dozen grams. Industrial electric arc furnace temperatures can be

up to 1,800 °C (3,272 °F), while laboratory units can exceed 3,000 °C (5,432 °F).

Arc furnaces differ from induction furnaces in that the charge material is directly exposed to

an electric arc, and the current in the furnace terminals passes through the charged material.

TEPES OF EAF:-

Two kinds of electric current may be used in Electric Arc Furnace.

Direct current (DC) Electric Arc Furnace.

Alternating current (AC) Electric Arc Furnace.

Three-phase AC Electric Arc Furnace with graphite electrodes are commonly used

in steel making.

INDUCTION FURNACE ELECTRIC FURNACE

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CONSTRUCTION: -

The furnace consists of the spherical hearth (bottom), cylinder shell and a

swinging water-cooled dome-shape roof.

The roof has three holes for consumable graphite electrode held by the clamping

mechanism.

Mechanism provides independent lifting and and lowering of each electrode.

The water-cooled electrode holder serve also as contact for transmitting electric

current supplied by water-cooled cables (tube).

The electrode and scrape from the star connection of three-phase current, in which

the scrape in common junction.

The furnace is mounted on a tilting mechanism for tapping the molten steel

through a tape hole with a pour spout located on a back of the shale.

To charge door, through which the slag components and alloying additives are

charged, is located on the front side of the furnace shell.

The charge door is also used for removing the slag (de-slagging).

OPERATION/ WORKING: -

The scrap is charged commonly from the furnace top.

The roof with the electrodes is swung aside before the scrap charging.

The scrap arranged in the charge bucket is transferred to the furnace by the crane and

the dropped into the shale.

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The lower voltage are selected for this first part of the operation to protect the roof

and walls from excessive heat and damage from the arcs.

The voltage can be increased and the electrodes raised slightly, lengthening the arcs

and increasing power to the melt.

BLAST FURNACEBASIC OXYGEN FURNACE

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FURNACES

Electric Arc Furnace Oxygen-Fuel, Oxygen Lance Furnace

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POURING (GATING DESIGN)

A good gating design should ensure proper distribution of molten metal without excessive

temperature loss, turbulence, gas entrapping and slags. If the molten metal is poured very

slowly, since time taken to fill the mould cavity will become longer, solidification will start

even before the mould is completely filled. This can be restricted by using super heated

metal, but in this case solubility will be a problem. If the molten metal is poured very faster,

it can erode the mould cavity. So gating design is important and it depends on the metal and

molten metal composition. For example, aluminium can get oxidized easily.

Gating design is classified mainly into two (modified: three) types:

Vertical gating,

Bottom gating

Horizontal gating.

Vertical gating:

The liquid metal is poured vertically, directly to fill the mould with atmospheric pressure at

the base end.

Bottom gating:

Molten metal is poured from top, but filled from bottom to top. This minimizes oxidation

and splashing while pouring.

Horizontal gating:

It is a modification of bottom gating, in which some horizontal portions are added for good

distribution of molten metal and to avoid turbulence.

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LADLES:

Ladles are used to transport molten metal from the melting furnace to the mould and vice

versa. These ladles consist of steel shell lined with a suitable refractory material like fire clay.

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SHAKEOUT MACHINE

Shakeout Tables separate the poured mold into the flask, casting, and sand (green and no

bake type). The casting deck configuration varies with the specific application. It can be

made removable for change out.

After the casting is reasonably cleaned of clinging sand, it is manually removed. The

shakeout sand passes down through the casting deck openings and is collected for discharge

through a bottom outlet.

These Shakeout Tables are all powered by the Cinergy drive System. The available widths

range from 2 ft. to 12 ft. in standard or heavy duty designs. The lengths are customized to our

customer’s needs.

Since the Cinergy drive System is energy efficient, power consumption is significantly

reduced. It is adjustable in operating stroke and frequency by simple electrical control. This

feature minimizes casting damage and noise. Maintenance checks are easily accomplished by

the simple “look and listen” principle.

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MATERIAL SEPRATION

In automatic foundry machines for the manufacture of castings in sand moulds it is known to

perform the pouring while the casting moulds are carried on a conveyor on which the filled

casting moulds are advanced to a knocking-out station provided with a grid. On this grid, the

castings are separated from the mould material which drops down through the grid and is

returned to the mould production apparatus. The intense heat from the metal poured damages

the mould sand which therefore must be regenerated between the successive applications. As

a rule, for the purpose of regeneration, a certain percentage of the mould sand is removed on

its way from the knocking-out grid to the mould production apparatus and is substituted by

unused material, which is mixed thoroughly with the remaining part of the mould sand,

possibly with the addition of special components for improving the properties of the mould

sand in various respects.

Prior art foundry machines of this type cause a great deal of inconvenience, such as a high

noise level and development of dust, heat and smell.

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SHOT BLASTING MACHINE

Shot blasting is a method used to clean, strengthen (peen) or polish metal. Shot blasting is

used in almost every industry that uses metal, including aerospace, automotive, construction,

foundry, shipbuilding, rail, and many others. There are two technologies used: wheel blasting

or air blasting.

When it comes to dealing with surface finishing and surface preparation problems, Rösler

Offers the total process solution! Our customers can choose between two processing

Technologies, Vibratory finishing or Shot blasting, which offer virtually unlimited

Possibilities. Through extensive processing trials, we always find the right finishing solution

For our customer’s needs.

This includes not only the development of a specific finishing process, but also the selection

of the right equipment and consumables.

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DEFECTS IN CASTING

A properly designed casting, a properly prepared mould and correctly malted metal should

result in a defect free casting. However, if proper control is not exercised in the foundry-

sometimes it is too expensive - a variety of defects may result in a casting.

These defects may be the result of:

(a) improper pattern design,

(b) improper mould and core construction,

(c) improper melting practice,

(d) improper pouring practice and

(e) Because of molding and core making materials.

(f) Improper gating system

(g) Improper metal composition

(h) Inadequate melting temp and rate of pouring

SURFACE DEFECTS:

Due to design and quality of sand molds and general cause is poor ramming.

BLOW: - Blow is relatively large cavity produced by gases

Which displace molten metal form.

SCAR:

Due to improper permeability or venting. A scare is a shallow blow.

It generally occurs on flat surf; whereas a blow occurs on a

Convex casting surface. A blister is a shallow blow like a scar

with thin layer of metal covering it.

SCAB: - This defect occurs when a portion of the face of a mould lifts

or breaks down and the recess thus made is filled by metal. When the

metal is poured into the cavity, gas may be disengaged with such

violence as to break up the sand which is then washed away and

the resulting cavity filled with metal. The reasons can be: - to fine sand, low permeability of

sand, high moisture content of sand and uneven moulds ramming.

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DROP: - Drop or crush in a mould is an irregularly shaped projection on the cope surface of

a casting. This defect is caused by the break-away of a part of mould sand as a result of weak

packing of the mould, low strength of the molding sand, malfunctioning of molding

equipment, strong jolts and strikes at the flask when assembling the mould.

BUCKEL: - A buckle is a long, fairly shallow, broad, vee depression that occurs in the

surface of flat castings. It extends in a fairly straight line across the entire flat surface.

INTERNAL DEFECTS:

PIN HOLES: - Pin holes are small gas holes either at the surface or just below the surface.

When these are present, they occur in large numbers and are fairly uniformly dispersed over

the surface.

WASH: - A cut or wash is a low; projection on the drag face of a casting that extends along

the surface, decreasing in height as it extends from one side of the casting to the other end.

It usually occurs with bottom gating castings in which the molding sand has insufficient hot

strength, and when too much metal is made to flow through one gate into the mold cavity.

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RAT TAIL: - A rat tail is a long, shallow, angular depression in the surface of a flat rating

and resembles a buckle, except that, it is not shaped like a broad vee.

The reasons for this defect are the same for buckle.

HOT TEAR: - Hot tears are hot cracks which appear in the form of irregular crevices with a

dark oxidized fracture surface. They arise when the solidifying met does not have sufficient

strength to resist tensile forces produced during solidification.

SHRINKAGE: - A shrinkage cavity is a depression or an internal void in a casting that

results from the volume contraction that occurs during solidification.

SWELL: - A swell is a slight, smooth bulge usually found on vertical faces of castings,

resulting from liquid metal pressure. It may be due to low strength of mould because of too

high a water content or when the mould is not rammed sufficiently.

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SHIFT : - Mold shift refers to a defect caused by a sidewise displacement of the mold cope

relative to the drag, the result of which is a step in the cast product at the parting line. Core

shift is similar to mold shift, but it is the core that is displaced, and (he dis-placement is

usually vertical. Core shift and mold shift are caused by buoyancy of the molten metal.

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TESTING OF MATERIAL

Mechanical Properties

Mechanical testing gives an evaluation of the metal and the casting to determine whether the

properties are in compliance with the specified mechanical requirements. Following are

common mechanical tests used in metal casting facilities.

Hardness testing: - the most commonly used procedure for mechanical property testing, it

provides a numerical value and is nondestructive. Hardness values generally relate to an

alloy’s machinability and wear resistance. The brinell hardness test uses a 10-mm diameter

carbide ball to indent a 3,000-kg load. The impressions are large enough to provide a

dependable average hardness. Rockwell hardness tests make smaller indented impressions,

which also can be satisfactory if the median of several values is used.

Tensile and impact testing: - conducted on test specimens of standardized dimensions, the

two most common types are tensile and Charpy impact. Tensile testing provides ultimate

tensile strength, yield strength, elongation and reduction of area data. Charpy impact testing

determines the amount of energy absorbed during fracture and is used to gauge ductility and

strength.

Service load testing: - usually conducted on the entire casting to evaluate its properties, it

can be conducted in a number of ways. Castings that must carry a structural load can have a

load applied in a fixture while the deflection and the load is measured. Pressure-containing

parts can be hydraulically tested to a proof load or destruction. Rotating parts can be spin

tested. These types of tests check the soundness of the casting, as well as its properties.

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PLANT LAY OUT

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CONCLUSION

In review this internship has been an excellent and rewarding experience. I have been able

to meet and network with so many people that I am sure will be able to help me with

opportunities in the future.

One main thing that I have learned through this internship is time management skills

as well as self-motivation. When I first started I did not think that I was going to be able to

make myself sit in an office for four hours a day, six days a week. Once I realized what I had

to do I organized my day and work so that I was not overlapping or wasting my hours. I

learned that I needed to be organized and have questions ready for when it was the correct

time to get feedback. From this internship and time management I had to learn how to

motivate myself through being in the office for so many hours. I came up with various

proposals and ideas that the company is still looking into using.

I am going to continue to work for Steve Levine Entertainment although I am still

keeping my options open for new opportunities. I enjoy this line of work, but I am not sure

if there is enough room to grow through this company. I will continue to work hard in my

position and hope to continue to learn about the industry and meet new people. This was

an excellent experience and I hope that other interns got as much out of it as

I did….!

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BIBLIOGRAPHY

Self-training

WEBSITES

o https://www.google.co.in

o https://en.wikipedia.org

BOOKS

Manufacturing technology by P N RAO

Manufacturing science by Amitabha ghosh

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