FOUNDRY-BASICS

SUBMITTED BY :- SUBMITTED TO:-

DEENA NATH O.P. SINGH
BIRAG JAIN
PRASHANT BHADORIYA
FOUNDRY:
” Foundry or casting is
the process of producing
metal/alloy component parts
of desired shapes by pouring
the molten metal/alloy into a
prepared mould (of that
shape) and then allowing the
metal/alloy to cool and
solidify. The solidified piece
of metal/alloy is known as a
CASTING”.
 INTRODUCTION OF TOOLS
 There are large number of tools and equipments
used in foundry shop for carrying out different
operations such as sand preparation, molding,
melting, pouring and casting.

 They can be broadly classified as hand tools, sand

conditioning tool, flasks, power operated
equipments,metal melting equipments and fettling
and finishing equipments.

 Different kinds of hand tools are used by molder in

mold making operations.
 LIST OF TOOLS
 1. Hand riddle  9. Lifters
 2. Shovel  10. Trowels
 3. Rammers
 11. Slicks
A. Hand rammer
B. Peen rammer  12. Smoothers
C. Floor rammer  13. Swab
D. Pneumatic  14. Spirit level
 4. Sprue pin  15. Gate cutter
 5. Strike off bar  16. Gaggers
 6. Mallet  17. Bellows
 7. Draw spike  18. Clamps, cotters and
 8. Vent roD wedges
HAND RIDDLE
SHOWEL
RAMMERS
 SPRUE PIN
 • Sprue pin is shown in Fig.
 It is a tapered rod of wood or iron which
is placed or pushed in cope to join mold
cavity while the molding sand in the cope
is being rammed.
 Later its withdrawal from cope produce a
vertical hole in molding sand, called sprue
through which the molten metal is poured
into the mould using gating system.
 It helps to make a passage for pouring
molten metal in mold through gating
system.
 STRIKE OFF BAR
Strike off bar is a flat bar having straight edge and is
made of wood or iron.
 It is used to strike off or remove the excess sand from
the top of a molding box after completion of ramming
thereby making its surface plane and smooth.
 Its one edge is made beveled and the other end is
kept perfectly smooth and plane.
 MALLET

 • Mallet is similar to a wooden hammer and is

generally as used in.carpentry or sheet metal
shops.
 In molding shop, it is used for driving the draw
spike into the pattern and then rapping it for
separation from the mould surfaces so that
pattern can be easily withdrawn leaving the
mold cavity without damaging the mold
surfaces.
 DRAW SPIKE
 Draw spike is shown.
 It is a tapered steel rod having a
loop or ring at its one end and a
sharp point at the other.
 It may have screw threads on
the end to engage metal pattern
for it withdrawal from the mold.
 It is used for driven into pattern
which is embedded in the
molding sand and raps the
pattern to get separated from
the pattern and finally draws out
it from the mold cavity.
 VENT ROD
 Vent rod is shown in.
 It is a thin spiked steel rod or wire carrying a pointed edge
at one end and a wooden handle or a bent loop at the
other.
 After ramming and striking off the excess sand it is
utilized to pierce series of small holes in the molding sand
in the cope portion.
 The series of pierced small holes are called vents holes
which allow the exit or escape of steam and gases during
pouring mold and solidifying of the molten metal for getting
asound casting.
 LIFTERS
 Lifters are shown in FIG.
 They are also known as cleaners or
 finishing tool which are made of thin sections of steel of
various length and width with one end bent at right angle.
 They are used for cleaning, repairing and finishing the
bottom and sides of deep and narrow openings in mold
cavity after withdrawal of pattern.
 They are also used for removing loose sand from mold
cavity.
 TROVELS
 Trowels are shown in Fig. 11.1(l, m and n).
 They are utilized for finishing flat surfaces and joints and
partings lines of the mold.
 They consist of metal blade made of iron and are equipped
with a wooden handle.
 The common metal blade shapes of trowels may be pointed or
contoured or rectangular oriented. The trowels are basically
employed for smoothing or slicking the surfaces of molds.
 They may also be used to cut in-gates and repair the mold
surfaces.
 SLICKS
 Slicks are shown in Fig. 11.1(o, p, q, and r).
 They are also recognized as small double ended mold
finishing tool which are generally used for repairing and
finishing the mold surfaces and their edges after
withdrawal of the pattern.
 The commonly used slicks are of the types of heart and
leaf, square and heart, spoon and bead and heart and
spoon.
 The nomenclatures of the slicks are largely due to their
shapes.
 SMOTHERS
Smothers are shown in FIG.

According to their use and shape they are given different

names. They are also known as finishing tools which
are commonly used for
repairing and finishing flat and round surfaces, round or
square corners and edges of molds.
 SWAB
 Swab is shown in Fig.I
 t is a small hemp fiber brush used for
moistening the edges of sand mould,
which are in contact with the pattern
surface before withdrawing the pattern. It
is used for sweeping away the molding
sand from the mold surface and pattern. It
is also used for coating the liquid
blacking on the mold faces in dry sand
molds.
 GATE CUTTER
Gate cutter is a small shaped piece of sheet metal
commonly used to cut runners and feeding gates for
connecting sprue hole with the mold cavity.
 BELLOWS
 Bellows gun is shown in Fig.
 It is hand operated leather made
device equipped with compressed
air jet to blow or pump air when
operated.
 It is used to blow away the loose
or unwanted sand from the
surfaces of mold cavities.
 CLAMPS, COTTERS AND WEDGES

 They are made of steel and are used for

clamping the molding boxes firmly together
during pouring.
 GAGGERS

 • Gaggers are pieces of wires or rods bent at

one or both ends which are used for
reinforcing the downward projecting sand
mass in the cope are known as gaggers.
 SPIRIT LEVEL

 Spirit level is used by molder to check

whether the sand bed or molding box is
horizontal or not.
 INTRODUCTION OF PATTERN

 Pattern is a mirror image or replica of the

component that has to be manufactured by
casting process.
 It may be also defined as a model around which
sand is packed to give rise to a cavity called
mold cavity.
 A pattern is required even if one object has to
be cast.
 The materials generally used for pattern are
wood, metal or plastics.
 USE OF PATTERN
 To form a cavity of proper shape and size in
the moulding material so that required
casting is obtained by molten metal.
 Providing seating surface for the core that
are used for making cavity i.e. core prints.
 Indirectly checks the dimensions and
measurements of the casting.
 Reduces casting defects
 Minimizes the cost of casting
 TYPES OF PATTERN
 Solid or single piece pattern
 Split pattern or two piece pattern
 Multi piece pattern
 Match plate pattern
 Gated pattern
 Skeleton pattern
 Sweep pattern
 Pattern with lose pieces
 Cope and drag pattern
 Follow board pattern
 Segmental pattern
 SOLID OR SINGLE PIECE PATTERN

 Simplest pattern
 Made in one piece
 Cheapest pattern
APPLICATION:
 Soil tamper
 Stuffing box
 Gland of steam engines
 TWO PIECE OR SPLIT PATTERN
 Pattern is split into two piece
 One part is in cope and other is in drag
 Easy withdrawal of pattern

APPLICATIONS:
 Spindles
 Steam valve bodies
 AK-47 rifle stock
 MULTI-PIECE PATTERN
 Pattern is split into more than two parts.
 Facilitates an easy moulding and withdrawal of pattern.

 Pattern may consists 3,4 or more numbers depending on

designs
APPLICATIONS:
 Lap joint

 Dowel joint

 Mitre joint
 MATCH PLATE PATTERN
 Patterns are made in two pieces one piece mounted
on one side and the other on other side of plate
called match plate.
 Plate may carry one or group of patterns mounted on
match plate.
 Along with pattern gates and runners are also
attached.
 Produces accurate castings at faster rates.
APPLICATIONS:
Generally used for small castings such as piston
rings of I.C. engines and rotor hub.
 GATED PATTERN
 In this the pattern are usually made of metals.
 In this multi-cavity moulds are produced & the
sections connecting different pattern serves as
gate and runner. This facilitates filling the mold
in better manner.
 Can produce many castings at one time and
hence saves time as well as cost.
APPLICATIONS:
Used for small castings such as corner bracket.
 SKELETON PATTERN
 Pattern is the Skeleton of desired shape, generally
mounted on the metal base.
 Skeleton is made from wooden strips and is filled with
loam sand and rammed. Extra sand is removed by
stickle.
 Cores are required if necessary.
 Applicable for large castings and is very economical
as less material costs.
APPLICATION:
Large castings such as turbines, water pipes, L-bends
etc.
 SWEEP PATTERN
 It is generally used for preparing large symmetrical
castings.
 It is made on wooden board and its sweeps the sand
in casting shape all around the circumference.
 Hence it saves lot of labour and time.
 It is used for production of large circular sections and
symmetrical shapes.
APPLICATIONS:
Symmetrical shapes such as wheels, rims, large
kettles of cast irons & bell shapes
 PATTERN WITH LOOSE PIECES
 Patterns consists of loose pieces for easy
withdrawal.
 These loose pieces form integral part of pattern
during molding.
 After mold is complete pattern is withdrawn
leaving this loose pieces.
APPLICATIONS:
 Pattern having projections or hanging parts.
 Rotor hub.
 Axel pin.
 COPE AND DRAG PATTERN
 In this pattern is made into two halves and both
are molded in different boxes.
 After completion of mold two boxes are
assembled to make a cavity.
 It is also known as two piece or split pattern.
APPLICATIONS:
 Flange pipe.
 Water Jacket of JCB head.
 Hose pipe coupling head.
 FOLLOW BOARD PATTERN
 It is a wooden board used to support during
moulding.
 Acts like a base seat for pattern.
 Follow board are used for those patterns which
has odd shapes.
 It supports weak pattern and also acts like
natural parting line.
APPLICATION:
It is used for casting master patterns for many
appliacations.
 SEGMENTAL PATTERN
 It is used for preparing circular castings.
 In this type it does not revolve continuously like
sweep pattern, instead prepares the mould by
parts.
 It completes one portion of the mold and then
moves to next position to make the next part of
the mold and so on till the mold is completed.
APPLICATIONS:
Used for circular work like rings, gears, wheels,
rims, pulleys etc.
TYPES OF PATTERN ALLOWANCES:

The various pattern allowances are:

1. Shrinkage or contraction
allowance.
2. Machining or finish allowance.
3. Draft of tapper allowances.
4. Distortion or chamber allowance.
5. Shake or rapping allowance.
 1.SHRINKAGE ALLOWANCE:
All most all cast metals shrink or contract
volumetrically on cooling.

The metal shrinkage is of two types:

1. Liquid Shrinkage:

2. Solid Shrinkage:
 2. MACHINING ALLOWANCE:
A Casting is given an allowance for machining, because:
i. Castings get oxidized in the mold and
during heat treatment; scales etc., thus
formed need to be removed.
ii. It is the intended to remove surface
roughness and other imperfections from
the castings.
iii. It is required to achieve exact casting
dimensions.
iv. Surface finish is required on the casting.
 3. DRAFT OR TAPER ALLOWANCE:

 It is given to all surfaces perpendicular

to parting line.
 Draft allowance is given so that the
pattern can be easily removed from the
molding material tightly packed around
it with out damaging the mould cavity.
FIG: TAPER IN DESIGN
 4. DISTORTION OR CAMBERED ALLOWANCE:
A casting will distort or wrap if :
i. It is of irregular shape,
ii. All it parts do not shrink uniformly i.e., some
parts shrinks while others are restricted from
during so,
iii. It is u or v-shape
5. SHAKE ALLOWANCE:
 A pattern is shaken or rapped by striking the
same with a wooden piece from side to side.
This is done so that the pattern a little is
loosened in the mold cavity and can be easily
removed.
 In turn, therefore, rapping enlarges the mould
cavity which results in a bigger sized casting.
 Hence, a –ve allowance is provided on the
pattern i.e., the pattern dimensions are kept
smaller in order to compensate the
enlargement of mould cavity due to rapping.
SAND-CASTING

Sand-casting is simple
in concept, but
demanding in
execution. It is a
process essential to
making basic and
advanced products. . .
it is also hazardous
and energy-intensive!
 CASTING TERMS:
Flask: A metal or wood
frame, without fixed
top or bottom, in
which the mold is
formed.
drag - lower molding
flask,
cope - upper molding
flask,
cheek - intermediate
molding flask used in
three piece molding.
CASTING TERMS:
Pattern

2. Pattern: It is the
replica of the final
object to be made.
The mold cavity is
made with the help of
pattern.
3. Parting line: This is
the dividing line
between the two
molding flasks that
makes up the mold.
4. Pouring basin: A small funnel shaped cavity at
the top of the mold into which the molten metal
is poured.
5. Sprue: The passage through which the molten
metal, from the pouring basin, reaches the mold
cavity. In many cases it controls the flow of
metal into the mold.
6. Runner: The channel through which the molten
metal is carried from the sprue to the gate.
7. Riser: A column of molten metal placed in the
mold to feed the castings as it shrinks and
solidifies. Also known as feed head.
8. Gate: A channel through which the molten metal
enters the mold cavity.
9. Core: A separate part of the mold, made of sand and
generally baked, which is used to create openings
and various shaped cavities in the castings.
10.Chaplets: Chaplets are used to support the cores
inside the mold cavity to take care of its own weight
and overcome the metallostatic force.
11. Vent: Small opening in the mold to facilitate escape
of air and gases.
SAND-CASTING
Basic materials & equipment for green sand-casting

Pattern
(a copy of the shape
you want to produce,
made of wood, plastic or
metal)

Sand,
mixed with clay binder &
water (so it will hold its
shape) plus coal dust to
improve surface finish

Container of molten metal

(filled from furnace) Top and bottom mold forms
(made of metal, open at top and bottom)

Rammer (tool to compact the sand;

often a pressing machine is used)
 SAND-CASTING
A very basic summary of the sand casting process. . .

First of all,
mix the sand.
THEN
1
MOLDING: 2 MOLDING:
Sand placed into Pattern placed into mold
bottom mold
form &
compacted
SAND-CASTING
MOLDING: Add
3 the top mold A tube or pipe provides
form a path to pour the
metal in

Pattern is still inside!

4 MOLDING: Fill top form

with compacted sand.
SAND-CASTING
MOLDING: Take In the middle of the
5 the top mold off sand is a cavity shaped
and remove like the pattern!
pattern & pipe or
post Pouring
hole

6 MOLDING: Replace the

top mold and fasten
securely!
SAND-CASTING

8 Wait for the metal to cool

(minutes to days,
7 CASTING: depending on the size of
Pour the metal (container is filled the casting)
from furnace immediately before
you are ready to pour)
SAND-CASTING
A copy of the pattern
has now been made
in metal

9
CLEANING. Sand is
cleaned off the part, the
“tab” where metal flowed
in must be removed.

8 SHAKE OUT: Break apart the two 10 Mold forms are reused
halves of the mold & take out the
part—usually requires vibrating or Sand is broken up,
striking the mold to break apart the 11 screened to remove
sand debris and clumps, and
sent for remixing
SAND MOULDING

PROCESS
SAND MOLD - OPENED
SAND MOLD - CLOSED
MIXING MOULDING SAND WITH BINDERS &
ADHESIVES
FILLING SAND IN MOULDING FLASKS
MELTING FURNACE
POURING MOLTEN LIQUID
KNOCK OUT
HEAT TREATMENT
MACHINING
FINAL PRODUCTS OF CASTING
 COMPLETE PROCESS AT A
GLANCE
1.
Mould
2.
3.

Dolly
4.
5.
Sprue
Pins
6.
7.
8.
9.
10.
11.
12.
13.