f and f manual

DEPARTMENT OF MECHANICAL ENGINEERING FOUNDRY & FORGING LABORATORY MANUAL

HKBK COLLEGE OF ENGINEERING,BENGALURU of 58

SAND TESTING

The need for systematic evaluation of the working qualities of molding sands has lead to the

development of a wide range of sand control tests. Molding sand is supposed to posses many

properties for its efficient functioning. These properties depend upon grain size, distribution,

content and type of binders, additives and moisture. Sand tests indicate the molding sand

performance and help the foundry men in controlling the properties of molding sands.

Production of sound casting largely depends upon uniform and good quality of molding

sands.

Sands are tested to know the following properties

1. Refractoriness

2. Permeability

3. Strength

4. Grain size and shape

5. Moisture content

Tests conducted on molding sand

1. Moisture content test

2. Clay content test

3. Grain fineness test

4. Permeability test

5. Strength tests

a) Green and dry compression

b) Green and dry shear

c) Green tensile

d)Transverse (Bending)

6. Hot strength

7. Refractoriness test

8. Mold hardness test



SIEVE ANALYSIS Aim: Find the average grain fineness number of the given sand

Apparatus: Sieve shaker, Sieve set, Weighing balance, Soft brush

Theory: The size of sand grains is designated by a number called Grain Fineness Number

that indicates the average size of grains in the mixture. The size is determined by passing

the sand through sieves having specified apertures which are measured in microns.

Foundry sand usually falls into the range 150-400 microns. The fineness test of molding

sand is of great value to the foundry man because the fineness of sand affects the

permeability and bond strength very much. Small castings require fine sand and large

castings require coarse sand.

Average grain fineness number can be found by the equation,

GFN = e/c

Where e = Sum of products of percentage sand retained in the sieve and corresponding

Multiplying factor

c = Sum of % of sand retained in the sieve.

Procedure:

1. Weigh 100 grams of sample sand.

2. Place the sand into the top sieve of a nest of ISO sieves on a vibrator. Vibrate for 10

minutes.

3. Remove the sieves. Beginning with top sieve, weigh the quantity of sand retained on

each sieve.

4. Calculate the percentage of sand retained on each sieve.

5. Multiply the percentage retained by the appropriate multiplying factor and add the

products.

6. Divide the total of the percentage retained to give average grain size.

Graphs: Sieve fineness Vs % retained

Result: Grain fineness number of the given sand is …………………….



SIEVE SHAKER

MODEL - VGH



TABULATION AND CALCULATIONS

G.FN =∑ e / ∑ c = total of e / total of c.

Sieve opening Number in

microns

(a)

Weight of sieve % Retained

(c)=(w2-wl)

Multiplying

factor (d)

Product

(e)=(c x d) Initial

(w1)

Final

(w2)

1700

5

850

10

600

20

425

30

300

40

212

50

150

70

106

100

75

140

53

200

Sieve pan

300



CLAY CONTENT TEST

Aim: Find the percentage of clay in the given sand.

Apparatus : Motorized stirrer timer, Indicator lamp, Glass jar, Syphon.

Preparation of Alkaline solution: Take 30 grams of sodium hydroxide. Dissolve in 50 c.c

of distilled water and make the volume to100 c.c by adding distilled water.

Procedure: 1. Take dried sample of 50 grams into glass jar and fill

halfway with water.

2. Add 10 c.c Alkaline solution of Sodium hydroxide fill the glass

jar with distilled water up to 50 mm mark.

3. Keep the jar on jar holder.

4. Let the solution stir for 8 to 10 minutes.

5. Remove the glass jar and rinse sand and fines adhering to

the stirrer into the glass jar by means of wash bottle.

6. Allow the sand to settle for 10 minutes, then fill the syphon with fresh

water and insert short leg into glass jar and syphon out the muddy water up

to 25 mm mark.

7. Add 10 cc of Sodium hydroxide solution; refill the glass jar with water up to

50 mm and stir for 5 minutes.

8. Allow the Sand to settle for 5 minutes.

9. Then again siphon out muddy water,

10. Continue the procedure till clear solution free of clay is obtained.

11. Transfer the washed sand with water into the sieve and dry completely

under infrared lamp.

12. Allow it to cool and weigh the sample.




Sl No. Weight of dry sand

sample

(a)

Weight of washed and

dried sand

(b)

a-b

% of clay content = ------- x 100

a



PERMEABILITY TEST

Aim: To determine the permeability number of the given green sand.

Apparatus: Sand rarnmer, Stripper, Weighing pan, Stop watch, Specimen tube,

Permeability meter.

Theory: Permeability is the ability of compacted sand to allow free escape of

gases. Permeability is measured by the quantity of air that passes through a sand sample in a

prescribed time under standard conditions. The instrument consists of a water tank, water

manometer, permeability chart, sealing boss with rubber, sleeve, 0 - P - D valve, syphon

attachment. The manometer scale is calibrated for 0 to 10 indicates pressure in grams per

sq.cm of water. There are two orifices, one orifice of 1.5 mm diameter and one orifice of 0.5

mm diameter. It is recommended to use small orifice for permeability number below 50

and large orifice for permeability number above 50.

Procedure: I. Take 150 grams of green sand and prepare the specimen of size

5.08 cm diameter and 5.08 cm height by using sand rammer.

2. Take the specimen tube with rammed specimen and place it inverted over

the rubber sealing boss.

3. Put the valve on 'p' position. Read the height of the water column in the

manometer tube.

3. Find out corresponding permeability number from the chart

fixed on the instrument.

4. Start the stop watch simultaneously when the valve on 'p' position

5. Note down the time required to pass 2000 cc of air passed

through the specimen.

6. Calculate the permeability number by using the formula.

7. Put the valve on '0' position.

Graphs: Permeability number Vs % of clay.

Permeability number V s % of moisture.

Result: Permeability number of the given green sand is ____________ _



PERMEABILITY METER

MODEL – VP

Air Tank

Water

Tank

Manometer

Permeability

Chart

Valve

Orifice

Rubber Boss

Zero adjustment Screw

Knob




Sl

No.

Silica sand

% grams

Moisture

% gram

Clay

% gram

Time taken

for 2000cc

of air to

pass

Orifice

pressure

grams/cm

Permeability

number

Calculations

VH

Permeability number, Pn = ------------

PAT Where V = volume of air passing through the specimen i.e 2000 cc

H = height of the specimen = 5.08 cm

P = pressure applied by the machine (manometer reading) in grams/cm

A = area of the specimen = (π /4) x (5.08)2

T = time in minutes for 2000cc of air passed through the sand specimen.



UNIVERSAL SAND TESTING MACHINE

The universal sand testing machine is used to test the strength of sand. Strength tests have

been devised to test the holding power of various bonding materials in green and dry sand.

The strength is governed by the amount of bonding material in the sand.

This machine consists of a pendulum weight and a pusher arm. They swing on

a shaft mounted on a suitable base. The pendulum weight and pusher arm are provided with

holes. The compression heads which hold the specimen during testing may be inserted into

the holes provided. A motor or hand wheel drive raises the pusher arm through an arc, thus

forcing the specimen to rise the pendulum weight and increasing the load on the specimen

until it breaks. The load on the specimen at any point is equal to the weight of the arm times

the sine of the angle at the pivot measured from the vertical starting position. When the

specimen breaks, returns the weight and the pusher arm to their initial position. On the base

frame is mounted a graduated scale. A magnetic rider is pushed along the scale ahead of the

rising pendulum weight until the specimen breaks. The rider then remains at the height

position attained thus indicating tue breaking load while the weight returns to its initial

position. Note down the reading directly from the corresponding scale.

Tests that can be performed on sand testing UTM

1) Compressive strength test

2) Shear strength test

3) Tensile strength test

4) Bending strength test



Pendulum type universal sand testing machine

I. Main body. 2. Pendulum 3. Pusher arm. 4. Wheel. 5. Scale 6. Specimen

7. Compression pads 8 BOl\omlocation 9. Top location 10. Lever 11. Top pulley

12. Cable. 13. Curvature I4. Adjusting screw 15. Main shaft 16.. Pusher arm pin

17. Clamping nut 20 Pusher plate 21. Rider (Magnet) 22. Rubber bumper.



COMPRESSION STRENGTH TEST Aim: To determine the green compression strength and dry compression strength of the

given

molding sand.

Apparatus: Weighing pan, sand rammer, specimen tube, stripper, Universal Testing

machine, compression pads

Procedure:

I) Sand specimen is prepared by using sand rammer of size 50.8 mm long and 50.8 mm

diameter

2) Prepared sand specimen is transferred to the Universal testing machine.

3) Keep the specimen between two compression pads.

4) Rotate the wheel in clockwise uniformly at the so as to obtain a green

compression reading of 500 grams/em" on the green scale in ] 5 sec.

5) Keep turning the hand wheel until the specimen breaks.

6) Immediately after the breaking of the specimen, the pendulum with the pusher plate

drops slightly down where as the max effective compression strength is indicated on

the scalby lower edge of the magnetic rider.

Read the scale according to the location being used i.e for bottom location read on

green

compression scale and for top location read on dry compression scale.

7) Reverse the switch due to which wheel rotates anti clockwise to take the pusher arm to

its

original position.

8) Repeat the same procedure by varying clay and moisture content of the green sand

and

note down the readings.

9) For dry compression strength prepare the specimen same as green compression

strength

test.

10) Dried the specimen in oven at 1500 - 200

0

11) The specimen should be allowed to cool in a dessicator until it has reached room

temperature.

13) Repeat the procedure same. as green compression strength test.

Graphs: 1) Green compression strength Vs % Moisture.

2) Green compression strength Vs % Clay.

3) Dry compression strength Vs % Moisture.

4) Dry compression strength Vs % .Clay.

Result: Green compression strength of the given sand is __ _________ _

Dry compression strength of the given sand is _____________ _




SL

NO.

Weight of silica

sand in % grams

Moisture in %

grams

Clay %

grams

Green

Compression

strength%

grams/cm2

Dry

compression

Strength.

grms/cm2



SHEAR STRENGTH TEST

Aim: To determine the green shear strength & dry shear strength of the given moulding sand.

Apparatus: Weighing machine, sand rammer, specimen tube, stripper, Universal testing

machine, shear pads.

Procedure: I) Sand specimen is prepared with a sand rammer of size 50.8mm Long and 50.8 mm

diameter.

2) Prepared specimen is transferred to universal testing machine.

3) Keep the specimen between two shear pads.

4) Rotate the wheel clockwise direction uniformly, until the specimen breaks.

5) Read the scale according to location i.e. for green shear strength read on

bottom location scale and for dry shear strength read on top location scale.

6) Repeat the same procedure by varying clay and moisture content the green sand and


7) For dry shear strength prepare the specimen same as green shear strength test.

8) Dried the specimen in an oven at 1500 - 200

0 c, time of one hour.

9) The specimen should be allowed to cool in a dessicator until it has reached room

temperature.

10) Repeat the procedure same as green shear strength test.

Graphs: 1) Green shear strength V s % moisture. 2) Green shear strength Vs % clay.

3) Dry shear strength V s % moisture.

4) Dry shear strength Vs % clay.

Result: Green shear strength of the given molding sand is _____________ _ Dry shear strength of the given molding sand is ------------------------




S.No Weight of

Silica Sand Moisture

Clay

Green shear Dry shear

Strength Strength % grams % grams % grams grms/cm2 grms/crn2



TENSILE STRENGTH TEST

Aim: To determine the green tensile strength & dry tensile strength of the given moulding

sand.

Apparatus: Weighing machine, sand rammer, specimen tube, stripper, Universal testing

machine, tensile core box.

Procedure:

1) Prepare a sand specimen with help of tensile core box.

2) Insert the specimen carefully in between the tensile jaws of the Universal testing

machine.

3) Tighten the clamping screw of the jaws so that distance between pendulum and pusher

arm rubber bumper is about 30 mm.

4) Remove the guide pin.

5) Rotate the wheel clockwise direction uniformly until the specimen breaks.

6) Read the scale according to location i.e. for green tensile strength read on

bottom

location scale and for dry tensile strength read on top location scale.

7) Repeat the same procedure by varying clay and moisture content of the green sand

and


8) For dry tensile strength prepare the specimen same as green tensile strength test.

9) Dried the specimen in an oven at 1050 - 110

0 c, time of on hour.

IO) The specimen should be allowed to cool in a desecrator until it has reached room

temperature.

11) Repeat the procedure same as green tensile strength test.

Graphs:

1. Green tensile strength V s % moisture

2. Green tensile strength Vs % clay.

3. Dry tensile strength Vs % moisture.

4. Dry tensile strength Vs % clay.

Result:

Green tensile strength of the given molding sand is ____________ _

Dry tensile strength of the given molding sand is




Sl

No.

Weight of

silica sand

Moisture

Clay

Green tensile

strength

%

grams/cm2

Dry tensile

strength

grams/cm2

% grams % grams % grams



MOULD HARDNESS TEST

Aim: To determine the green surface hardness of the sand mould.

Apparatus: Mould hardness tester.

Theory: The hardness to which molding sands are rammed affects two important physical

properties of a sand mould.

1) The ability of the sand mould surface to withstand the pressure of Molten

metal.

2) The degree of permeability of the sand mould. Mould surface hardness is

the

resistance offered by the surface of a Green sand mould to penetration by a

loaded plunger.

Recommended mould hardness readings are

Soft rammed moulds ----------------- below 70.

Medium rammed moulds -------------- 70 to 80.

Hard rammed moulds ----------------- above 80.

Procedure:

1) Apply the instrument vertically, placing the tip on the mould surface of

which hardness is to be measured.

2) Gently press on the surface until the surface of the bottom ring contracts

the mould surface throughout the periphery.

3) The depth of the penetration of the tip into the mould indicates the green

hardness which is indicated on the dial directly.

Result: The hardness of the given green sand mould is _______________ _



Viva Vocae questions

What is pattern?

What are the different tools used in foundry?

What are the different names of the molding boxes?

What are the main characteristics which good molding sand should posses?

What is meant by green strength and dry strength of the molding sand?

What are the main constituents of the molding sand?

What are the different types of patterns?

What is meant by allowance relative to pattern?

What are the different allowances given to pattern?

What is the use of the strike off bar?

What is the use of riddle?

What is the difference between runner and riser?

What is the use of lifter?

What is the use of shovel?

What are the different casting defects?

What is meant by shrinkage allowance?

What is meant by finish allowance?

What is core? Why core is used?

What is sprue pin? And why it is tapered?

What is riser and why it is required?

Differentiate between molding sand, parting sand, facing sand.

What is ramming? And what is the effect of improper ramming?

What are the different properties of molding sand?

What is the difference between natural sand and synthetic sane?

Why pattern is made larger in size than casting?

What are the different pattern materials?

What is meant by permeability number?

What is the use of adding alkaline solution in clay content test?

What are the sizes of orifices you are using in permeability test?

What is use of providing vent holes in molding process?

What is size of sand specimen to conduct green compression strength test?

What is the formula to find the permeability number?



FOUNDRY



CASTING

A metal Casting may be defined as a metal object produced by pouring molten metal in

to a mould which has the desired shape of the casting and allow the molten metal to solidify.

Castings are always smaller in dimensions than the pattern from which they are made. This is because thermal contraction occurs as the metal cools from its solidification temperature to room temperature.

A pattern is a duplicate of the part to be cast. A pattern is made full size. A pattern is

made slightly larger in size, to compensate for the shrinkage and finish.

Pattern size = Actual size + Shrinkage allowance + Finish allowance

Types of patterns: There are several types of patterns used in the production of castings.

1. Solid pattern: Solid pattern is used for producing single or small quantity production.

2. Split pattern: This type of pattern is used commonly where two boxes are used and

pattern is split through joint line. The two halves are located with dowels.

Molding sand is used to fill the molding box. There are two types of moulding sand. I. Natural sand i.e sand containing the silica grains and clay bond as found. 2. Synthetic sand

i.e sand composed of washed and graded silica grains, with desired type and amount of clay

bond added. Molding sand must be capable of a) Maintaining the shape of the pattern b) Withstanding heat c) Allowing gases to escape.

Properties of molding sand :

1. Cohesiveness: It is the ability to retain shape impression after the removal of the

pattern and during pouring and solidifying of the metal.

2. Refractoriness: It is the property of sand to with stand the heat of the molten metal

with out fusing.

3. Permeability: It means that the mould is porous enough to allow gases evolve during

pouring to escape.

4. Strength of the mould: It means that the mould is strong enough to support the

weight of hot metal and necessary sand cores.



MOULDING TOOLS

Rammer

Rammers are used for packing the sand in a mould. Rammers have a flat end called the butt

and a wedge shaped end termed as the peen.

Strike off bar is a straight piece of wood or metal. It is Used to level the top surface of the mold

Flasks are made in various sizes and shapes to accommodate various castings. Flasks are usually rectangular In shape. Flasks are made of cast metal or wood.

moulding board



Sprue pins and riser pins are tapered wooden pins.

These are used as patterns for forming gate

spaces and risers.

A sprue cutter is a piece of used to cut sprue.

Gate cutters are used to cut gates and sometimes runners. A gate cutter is usually a piece of

bent into a u shape.

A lifter has one end slightly flattened and bends to 90 degree. It is used for lifting and

removing loose sand from deep pars of the mold.



Moulding tools

Trowels, slicks, spoons and lifters are finishing tools. These tools are used by the molder to

repair molds after the pattern has been withdrawn. There are over 60 different shapes of

finishing tools.

English Trowels Molder’s Trowel

Leaf and square

Leaf and spoon

Long heart trowel

Scotch cleaner



Broad heart trowel

Bellows for cleaning loose sand

from mold

Sieve for facing sand wooden hand rammer

Sand Showel

Boss tool Spoon tool

Scotch cleaner



Straight bead

English cleaner

Girdar tool

Flange cleaner



Smoothers

Flange cleaner



FOUNDRY MODELS



QUARE CHIPPING BLOCK

Aim: To prepare a mould of Square chipping block as per dimensions as shown in the

diagram.

Tools Required: Molding box(2 no's), Peen and Butt Rammer, Strike off bar, Trowel,

Shovel, sprue, Lifter, Vent rod, Draw spike, Try square, Steel rule.

Sequence of operations:

1. Mix the molding sand properly.

2. Apply bentonite mixture to all inner sides of the molding boxes.

3. Keep the drag molding box on the follow board.

4. Fill the Drag molding box with molding sand with the help of shovel.

5. Ram the molding sand with peen rammer first, latter with Butt rammer.

6. The excess sand is removed by using a strike off bar.

7. Turn over the Drag molding box.

8. Sprinkle the dry silica sand on the drag molding box.

9. Keep the Cope on the top of the drag along with Sprue and riser and fill with

molding Sand.

10. Ram the molding sand with rammer and later strike off the excess sand from the

cope

Molding box.

l l. Keep the cope and drag molding boxes separately.

I2.Mark the100x100 mm square on the drag portion by using Try square and steel

Rule.

I3. Remove the molding sand up to a depth of 25 mm by using lifter from the

drag.

14. Mark the 50X50 mm square on the cope portion by using Try square and steel

rule.

I5. Remove the molding sand up to a depth of25mm by using lifter from the cope.

I6. Cut the runner and gate in the drag portion.

I 7.Keep the cope portion on the top of the drag with proper alignment.

I8.Now the mould of square chipping block as per the dimensions shown in the

diagram is ready for pouring.



SQUARE CHIPPING BLOCK

Required

Dimensions

Actual

Dimensions



HEXAGON WITH CYLINDER

Aim: To prepare a mould of Hexagon with cylinder as per dimensions as shown in the

diagram.

Tools Required: Moulding box(2 no's), Peen and Butt Rammer, Strike of bar,

Trowel,

Shovel, Sprue, Lifter, Vent rod, Draw spike, Try square, Steel

rule.


I. Mix the moulding sand properly.

2. Apply bentonite mixture to all inner sides of the moulding boxes.

3. Keep the drag moulding box on the fallow board.

4. Fill the Drag moulding box with moulding sand with the help of shovel.

5. Ram the moulding sand with peen rammer first, latter with Butt rarnrner.


7. Turn over the Drag moulding box.

8. Sprinkle the dry silica sand on the drag moulding box.

9.. Keep the Cope moulding box on the top of the drag along with Sprue and riser and

filled

with moulding Sand.

10.Ram the moulding sand with rammer and latter strike off the excess sand from the

cope

moulding box.

l l.Keep the cope and drag moulding boxes separately.

I2.Mark the 100 mm Hexagon on the drag portion by using Try square and

steel rule.

13. Remove the moulding sand up to a depth of25mm by using lifter from the

drag.

14. Mark the cfl30mm circle on the cope portion by using compass and steel

rule.

15. Remove the moulding sand up to a depth of25mm by using lifter from the

cope.

16.Cut the runner and gate in the drag portion.

17.Keep the cope portion on the top of the drag with proper alignment.

I8.Now the mould of Hexagon with cylinder block is as per the dimensions shown

in the iagram is ready for pouring.



HEXAGON WITH CYLINDER

Required

Dimensions

Actual

Dimensions



STEP PULLEY (SINGLE PIECE)

Aim:To prepare a mould of Step pulley as per dimensions as shown in the diagram.

Tools Required: Moulding box(2 no's), Peen and Butt Rammer, Strike of bar, Trawel, Shovel, Sprue, Lifter, Vent rod, Draw spike, Try square, Steel rule.


1.Mix the moulding sand properly.



4. Keep the pattern(step pulley) at the center of the moulding box.

5. Fill the Drag moulding box with moulding sand with the help of Shovel.

6. Ram the moulding sand with peen rammer first, latter with Butt rammer.




10. Keep the Cope moulding box on the top of the drag along with sprue and riser and

filled

with moulding Sand.

11 .Ram the moulding sand with rammer and latter strike off the excess sand from

the cope moulding box.

12.Keep the cope and drag moulding boxes separately.

13Remove the pattern (step pulley) from the drag moulding box with the help of draw

Spikes.

14. Cut the runner and gate in the drag portion.

15.Keep the cope portion on the top of the drag with proper alignment.

I6.Now the mould of Step pulley is as per the dimensions shown in the diagram is

ready for pouring.



STEP PULLEY (SINGLE PIECE)

Required

Dimensions

Actual

Dimensions



DUMBBELL

Aim: To prepare a mould of Dumbbell as per dimensions as Shown in the diagram.

Tools Required: Moulding box(2 no's), Peen and Butt Rammer, Strike of bar, Trawel,

Shovel, Sprue, Lifter, Vent rod, Draw spike, Try square, Steel rule


1. Mix the moulding sand properly.

2.Apply bentonite mixture to all inner sides of the moulding boxes . ., -'. Keep the drag moulding box on the fallow board.

4. Keep the half pattern of the Dumbbell at the center of the moulding box

5. Fill the Drag moulding box with moulding sand with the help of Shovel.





10..Keep the Cope moulding box on the top of the drag along with half pattern

perfectly

align.on the lower half pattern of the Dumbbell.

l l. Keep sprue and riser and filled with moulding Sand.

I2. Ram the moulding sand with rammer and latter strike off the excess sand from

the cope

moulding box.

13. Keep the cope and drag moulding boxes separately. I4.Remove the pattem(Dumbbell) from the drag and cope moulding boxes with the help of

draw spikes.

15.Cut the runner and gate in the drag portion.

16. Keep the cope portion on the top of the drag with proper alignment.

17. Now the mould of Dumbbell is as per the dimensions shown in the diagram is

ready for pouring.



DUMBBELL



GROOVED PULLEY (TWO PIECE)

Aim: To prepare a mould of Grooved pulley as per dimensions Shown in the diagram.

Tools Required: Moulding box(2 no's), Peen and Butt Rammer, Strike off bar,

Trowel,

Shovel, Sprue, Lifter, Vent rod, Draw spike, Try square, Steel

rule.


1. Mix the moulding sand properly.



4. Keep the halfpattern(Grooved pulley) at the center of the moulding box.

5. Fill the Drag moulding box with moulding sand with the heir of Shovel.





10. Keep the Cope moulding box on the top of the drag along with half pattern perfectly

align on the lower half pattern.

11. Keep sprue and riser and filled with moulding Sand.

10.Ram the moulding sand with ram mer and latter strike off the excess sand from

the cope

moulding box.

l l.Keep the cope and drag moulding boxes separately.

12. Remove the pattern(Grooved pulley) from the drag and cope moulding boxes with

the

help of draw spikes.

I3.Cut the runner and gate in the drag portion.

I4.Keep the cope portion on the top of the drag with proper alignment.

I5.Now the mould of Grooved pulley is as per the dimensions shown in the diagram is

ready for pouring.



GROOVED PULLEY (TWO PIECE)



FORGING



FORGING

Forging is the process of plastically deforming metals or alloys to a specific shape

by compression. The compressive force is exerted by hammer, a press or by rolls etc. It is a

process of producing machine or structural parts that must withstand shock or sudden impact

loads. Forging is made by heating the metal piece to plastic state and thereby hammering,

pressing or bending it into shape. Forging may be made by hand by blacksmith or by various

types of power operated machinery

Forging processes: The load requirement for forging has lead to several types.

1. Hand forging-smith forging.

2. Open die forging.( a. hammer forging. b. press forging)

3. Drop forging.

4. Upset forging

5. Roll forging.

Drop forging: Drop forging is the process of forming the desired shape by placing a heated

bar or billet on the lower half of a forging die and placing the top half of the die into the

metal by means of a power driven machine called a drop hammer.

Press forging: In this process the heated billet is squeezed between dies. The pressure is

applied by a forging press which completes the operation in a single stroke. Large forgings

are generally shaped by this method.

Roll forging: Roll forging involves the passing of a heated bar between revolving rolls that

contain an impression of the required shape. It is a process designed chiefly to reduce short

thick sections to long slender pieces.

Advantages of forging:

1. Forged components have good strength.

2. The forged components have high toughness and good fatigue properties.

3. Forged parts are characterized by a fibrous structure.

4. Forgings are free from porosity, surface inclusions or other defects.

5. When metal is forged, both strength and ductility increase considerably along the

lines of flow.

6. Forged parts are uniform in size and shape.



FORGING TOOLS 6.

Swage Block: Swage block is a rectangular block with varying sizes of vee and half round

notches on its edges. Round, Square and rectangular holes through its face. The holes in the

face may be used for punching and bending and the grooves on its edges may be used for

accommodating work of various sections.

T1lE SIlAGE BLOCI{

Anvil: Anvil is used as a mount for pairs of tools between

which the work is forged by

hammer blows. The main body of the anvil is made of mild steel, with a hardened top face

welded on. The beak is soft and, with an increasing diameter of cross section. Beak is useful

for producing bends of different radii. The edge between the beak and the anvil face is soft

and can be used as a base for cutting operation with hot chisels.



Swaees: Swages are used in pairs to shape hot metal. They are supplied in pairs ,top and

bottom. The bottom swage is placed in the square hole of the anvil and the top swage is hit with a sledge hammer. Between them the work is brought down to size and is given a

good cylindrical finish.

Fullers: Fullers are blunt nosed chisels. They are used to reduce the thickness of hot metal. They may be held with hand or fitted with a rod handle. Bottom fullers may be inserted in the square hole of the anvil.

Chisels: Chisels are used to cut metal. There are two types of chisels. I) cold chisels for cutting cold metal. Its edge is hardened and tempered, and 'its point angle is 60° 2) 1101 chisels are used for cutting red hot metal and do not have to be as sharp as cold chisels. The

hot chisel has a point angle Df 30° and is soft. ..



FORGING MODELS



SQUARE SHAPED MODEL

Aim: To prepare a model of square shaped cross section from the Round bar.

Tools Required: Anvil, Tongs, Flatteners, Swage block, Sledge Hammer.


1. First the given specimen is heated in a furnace to a red hot state below its

recrystallization temperature.

2. With the help of Tong, work piece is taken out from the furnace, place on the

anvil and do the hammering operation. .

3. The process is continued till it get the required shape and dimensions

4. Then using flatteners finishing is done on the given job.

5. Then using scale and try square the accuracy of dimension is checked



Calculations Volume of the given round bar,

V= πd2xl

4

When d= diameter of the bar

l=length of the bar

Volume of square rod = a x a x h

Volume of the given round bar = volume of square rod

πd2xl = a x a x h

4

Equating the two, any unknown can be calculated.



HEXAGONAL SHAPED MODEL

Aim: To prepare a model of square shaped cross section from the Round bar.





2. With the help of Tong, work piece is taken out from the furnace, place on the

anvil and do the hammering operation. .

3. The process is continued till it get the required hexagonal shape and

dimensions.

4. . Then using flatteners finishing is done on the given job.

5. Then using scale and try square the accuracy of dimension is checked.




V= πd2x l

4


l=length of the bar

Volume of hexagonal rod = area of base with side of length a multiplied by its height

Volume of the given round bar = volume of hexagonal rod

πd2x l = 6 3 x a

2 x h

4 4

Volume of the given round bar = volume of hexagonal rod




SQUARE HEAD BOLT

Aim: To prepare a model of square head bolt from the Round bar.





2. With the help of Tong, work piece is taken out from the furnace and do the

upsetting operation. .

3. Before doing Upsetting operation, 3/4lh

of the work piece is quenched in

water to avoid buckling.

4. Diameter of the one end of the bar is increased by 30mm up to a length

of 20mm by upsetting operation.

5. Then the specimen end of 30mm diameter is hammered to form a square head.

6. Finally the specimen is placed in the swage block and with the help of

flatteners, the top of the square head is finished by slight hammering.




V= πd2xl

4


l=length of the bar

Volume of the bolt = volume of bolt head + volume of shank

=a x a x h + πd2 x L

4

Volume of the given round bar = volume of the bolt




HEXAGON HEAD BOLT

Aim: To prepare a model of Hexagonal head bolt from the Round bar.



1. First the given specimen is heated in a furnace to a red hot state below its re-

crystallization temperature.


upsetting operation.

3. Before doing Upsetting operation, 3/4th

of the work piece is quenched in water to

avoid buckling.

4. Diameter of the one end of the bar is increased by 30mm up to a length

of20mm by upsetting operation.

5. Then the specimen end of30mm diameter is hammered to form a Hexagonal head.

6. Finally the specimen is placed in the swage block and with the help of flatteners; the

top of the Hexagonal head is finished by slight hammering.




V= πd2x l

4


l=length of the bar

Volume of the bolt = volume of bolt head + volume of shank

πd 2x l = 6 3 x a

2 x 20 + πd

2 x 70

4 4 4

Volume of the given round bar = volume of the bolt




L-SHAPE NAIL

Aim: To prepare a model of L-shape nail from the Round bar.



1. First the given specimen is heated in a furnace to a red hot state below its re-

crystallization temperature.


drawing operation.

3. Keep the specimen on the Anvil and apply force by using sledge hammer and

convert the round bar to the square bar.

4. Keep the square bar in the swage block square hole and bend the bar into L-shape by

applying force by using hammer at 3/4th

of its length.

5. Finish the L-shape using set hammer.

6. The shorter side of the rod is hammered at an angle to form sharp edge of the four

sides.

7. Finish the model using set hammers.




V= πd2xl

4


l=length of the bar

Volume of L-shaped nail = volume of (vertical) square prism + volume of (horizontal)

prism

+ Volume of square based prism

= 10 x 10 x 40 + 10 x 10 x L+1/3 x 10 x 10 x 25

L can be calculated



Viva vocae questions

I) what is forging?

2) Name the different forging processes.

3) Give the advantages of forging.

4) Anvil is made of which material?

5) What are the uses of swage block?

6) What is the mass of the sledge hammer?

7) What is the difference between hot chisel and cold chisel?

8) Which processes are used in forming the head of a bolt?

9)Which steel is best suited for forging?

10) Sketch open-die forging and explain

11)Name some of the components that are manufactured by closed die forging.

12) What is meant by heat treatment?

13)Can the forged components be used directly without subjecting them to heat treatment?

14) Name some of the special forging processes.

1) Name some of the forging machines.

16) Name some of the heating furnaces for forging.

17) What is closed die forging?

18) What are the components that are forged?

19) Which component is better manufactured by casting or forging and why?

20) What are the forging temperatures?

21) What is the use of tongs? And list out the types of tongs.

22) What is the use of punches and drifts?

23) What is the difference between drawing down and upsetting?

24) What is meant by drifting?

25) What is meant by fullering?



DEPARTMENTAL OF MECHANICAL ENGINEERING PROGRAM EDUCATIONAL OBJECTIVE (PEO’s)

PEO 1: To impart education and enable the students to become graduates in mechanical

engineering and to be able to pursue higher studies or to join the work force.

PEO 2: To enable students acquire in depth knowledge in chosen field of engineering and

technology and be competent to apply the same.

PEO 3: To make graduates to achieve a high level of technical expertise in Mechanical

Engineering and able to work in inter disciplinary areas.

PEO 4: Graduates will be able to fulfill the expectations of the society and to create

professionally superior and ethically strong global manpower.

PEO 5: To provide an integrated experience to develop skills to face the challenges and to

pursue lifelong learning needed to prepare the graduates for successful career.

PROGRAM OUTCOMES (PO’S):

(a) an ability to apply knowledge of mathematics, science and engineering in Mechanical

Engineering

(b) an ability to design and conduct experiments, as well as to analyze and interpret data

related to Mechanical Engineering.

(c) an ability to design a system, component, or process to meet desired needs within

realistic constraints such as economic, environmental, social, political, ethical, health

and safety, manufacturability, and sustainability.

(d) an ability to function on multidisciplinary teams.

(e) an ability to identify, formulate, and solve (complex) engineering problems.

(f) an understanding of professional and ethical responsibility.

(g) an ability to communicate effectively.

(h) the broad education necessary to understand the impact of engineering solutions in a

global, economic, environmental, and societal context.

(i) a recognition of the need for, and an ability to engage in life-long learning.

(j) a knowledge of contemporary issues.

(k) an ability to use the techniques, skills, and modern engineering tools necessary for

engineering practice.

(l) an Ability to apply multivariate calculus and differential equations to model, analyze,

design, and realize physical systems, components or processes.

f and f manual

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