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Page 1: Casting and foundry
Page 2: Casting and foundry

Foundry

Shri Govindram Seksaria Institute Of Technology And Science

23 Park,Road Indore

1 432 8765 9 10 1211

Submitted To:Mr. Dhirendu Somani

Page 3: Casting and foundry

Foundry

Shri Govindram Seksaria Institute Of Technology And Science

23 Park,Road Indore

1 432 8765 9 10 1211

Submitted To:Mr. Dhirendu Somani

Page 4: Casting and foundry

Foundry

Shri Govindram Seksaria Institute Of Technology And Science

23 Park,Road Indore

1 432 8765 9 10 1211

Submitted To:Mr. Dhirendu Somani

Page 5: Casting and foundry

Foundry

Shri Govindram Seksaria Institute Of Technology And Science

23 Park,Road Indore

1 432 8765 9 10 1211

Submitted To:Mr. Dhirendu Somani

Page 6: Casting and foundry

Table Of Contents#1 Casting and its Applications

#2 Important Casting Terms

# 3 Steps involved in sand casting

#4 Pattern Making and its Types

#5 Moulding Sand

#6 Casting Defects

Page 7: Casting and foundry

CASTING

Page 8: Casting and foundry
Page 9: Casting and foundry

Take Molten Metal

Molten Cavity

Take Out the desired material

POUR

SOLIDIFY

What Is Casting?

Page 10: Casting and foundry

EXTRAS

The solidified object is called casting and this process is known as founding.Mould is made of some heat resisting material. Hence sand is most often used for casting process.

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Advantages&

Disadvantages

Advantages• Molten metal flows from any section

and hence intricate shapes can be made.

• Tools required are simple and inexpensive.

• Weight reduction in design can be achieved as it is possible to place required amount of material where exactly required.

Disadvantages• Dimensional accuracy and surface

finish are not adequate for the final application.

• Sand casting process is labour intensive.

• Thin walled sections cannot by sand casting.

• Mould cavity can be used only once.

AD

Page 12: Casting and foundry

Applications

A

Page 13: Casting and foundry

Machine Bed

Piston Rings

Mills Wheels

1.• Cylinders and

cylinder heads for air-cooler IC engines.

2.

• Automobile transmission parts

• Aerospace and rocket components,

3.• Surgical

Instruments• Gears

4.

• Household applications

• Kitchen equipment

• Furniture and fittings

Page 14: Casting and foundry

Important Casting Terms

Page 15: Casting and foundry

Moulding Flask : It holds the sand mould intact. The top half is called cope and the bottom half is called drag. Any intermediate flask used in case of 3 piece moulding is called check.

Pattern :It is the replica of the final object to be made and is used for preparing the mould cavity.

Parting Line :It is the dividing line b/w the two moulding flasks.

Bottom Board :This is used at the start of the moulding process. Pattern is placed on it, sand is sprinkled and rammed in the drag.

Moulding Sand : It is the refractory material used for making moulding cavity. It is a mixture of silica sand, clay and moisture n appropriate proportions.

Page 16: Casting and foundry

Core: This is used for making hollow cavities in the casting.

Pouring basin :It is a small funnel shaped cavity at the top of the mould into which the molten metal is poured.

Sprue :The passage through which the molten metal reaches the mould cavity and controls the flow of metal into the mould.

Runner:The passage way in the parting line through which the metal flow is regulated before it reaches the mould cavity.

In gate: The actual entry point through which the metal.

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Riser: Reservoir of molten metal provided in the casting so that hot metal can flow back into the mould cavity where there is a reduction in volume of metal due to solidification.

Chaplets: They are used to support cores inside the mould cavity to take care if its own weight and overcome metallostatic forces. They are made of same material as that of molten metal so that they melt in the process of casting.

Chills:These are the metallic objects placed in the chills to increase the cooling rate of casting to provide uniform cooling rate.

Page 18: Casting and foundry

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 a casting 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

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Steps For Making Moulds

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#1 Pattern MakingPrincipal tool during the casting

process. Replica of the object to be made b casting with some modifications.

Main modifications are the addition of pattern allowances, and the provision

of core prints. If the casting is to be hollow,

additional patterns called cores are used to create these cavities in the

finished product. The quality of the casting produced depends upon the material of the

pattern, its design, and construction.

Page 21: Casting and foundry

In horizontal molding, the top half is called the cope, and the bottom half is called the drag.

In vertical molding, the leading half of the mold is called the swing, and the back half is called the ram.

When the patterns withdrawn from the molding material the imprint of the pattern provides the cavity. The mold cavity, together with any internal cores as required, is ultimately filled with molten metal to form the casting.

If the casting is to be hollow, additional patterns, referred to as core boxes, are needed to shape the sand forms, or cores.Thus the void between the mold and core eventually becomes the casting.

Page 22: Casting and foundry

1.A pattern prepares a mold cavity for the purpose of making a casting.

2. A pattern may contain projections known as core prints if the casting requires a core and need to be made hollow. 3. Runner, gates, and risers used for feeding molten metal in the mold cavity may form a part of the pattern. 4. Patterns properly made and having finished and smooth surfaces reduce casting defects. 5. A properly constructed pattern minimizes the overall cost of the castings.

Page 23: Casting and foundry

Materials for pattern making include wood, metals and alloys, plastic, plaster of Paris, plastic and rubbers, wax, and resins.

Characteristics of the material should be1. Easily worked, shaped and joined 2. Light in weight3. Strong, hard and durable 4. Resistant to wear and abrasion 5. Resistant to corrosion, and to chemical reactions 6. Dimensionally stable and unaffected by variations in

temperature and humidity 7. Available at low cost The most commonly used pattern material is wood,

since it is readily available and of low weight. Also, it can be easily shaped and is relatively cheap.

The main disadvantage of wood is its absorption of moisture, which can cause distortion and dimensional changes.

Page 24: Casting and foundry

Solid pattern – A solid pattern is a model of the part as a single piece. easiest to fabricate, but can cause some difficulties in making the mold. The parting line and runner system must be determined separately. used for geometrically simple parts that are produced in low quantities.

Split pattern – models the part as two separate pieces that meet along the parting line of the mold. Using two separate pieces allows the mold cavities in the cope and drag to be made separately. used for parts that are geometrically complex and are produced in moderate quantities.

Types Of Patterns

Page 25: Casting and foundry

Match-plate pattern – similar to a split pattern, except that each half of the pattern is attached to opposite sides of a single plate. The plate is usually made from wood or metal. ensures proper alignment of the mold cavities in the cope and drag the runner system can be included on the match plate. used for larger production quantities and when the process is automated.

Cope and drag pattern – similar to a match plate pattern, except that each half of the pattern is attached to a separate plate and the mold halves are made independently. the plates ensure proper alignment of the mold cavities in the cope and drag the runner system can be included on the plates. desirable for larger castings, where a match-plate pattern would be too heavy and cumbersome. used for larger production quantities and when the process is automated.

Gated Patterns –a loose pattern that has the gating system included as a part of the pattern.eliminates the time and inconsistency associated with hand-cutting the gates and runners.the consistency of molten metal flow into the casting and feeding of the casting during solidification is improved. appropriate for pouring small quantities of castings when quick turn around and low cost are important.

Page 26: Casting and foundry

Molding is the operation necessary to prepare a mold for receiving the metal.

Consists of ramming sand around the pattern placed in support, or flask,

removing the pattern, setting cores in place, and creating the gating/feeding

system to direct the metal into the mold cavity created by the pattern, either by cutting it into the mold by hand or by

including it on the pattern, which is most commonly used.

#2 Molding

Page 27: Casting and foundry

Melting and pouring are the processes of preparing molten metal of the proper composition and temperature and pouring this into the mold from transfer ladles.

#3 Pouring

Page 28: Casting and foundry

Cleaning includes all the operations required to remove the gates and risers that constitute the gating/feeding system and to remove the adhering sand, scale, parting fins, and other foreign material that must be removed before the casting is ready for shipment or other processing.

#4 Cleaning

Page 29: Casting and foundry