ENGINEERING PRACTICES LABORATORY LAB MANUAL

(MECHANICAL & CIVIL)

ACADEMIC YEAR: 2020-2021

Name of the student:

Reg. No:

Course & Branch: B.Tech / Information & Technology

Year / Semester: I / II

Sub. Code: 20ESGE201

 PLUMBING

INTRODUCTION
Plumbing deals with the laying of a pipeline. A craftsman may be perfectly proficient with
the hammer, saw and other tools, but the faces difficulties with leaking pipes and overflowing
toilets. Many people rush to a plumber on seeking a tripping pipe, but a person with a little
knowledge of the sanitary system can control this problem easily, saving time and, one with help of
few tools.

PLUMBING TOOLS
The tools used by a plumber can be classified as follows
1. Pipe wrench 4. Pipe vice 6. Pipe cutter

2. Hacksaw 5. Dies 7.Files and Rasps

3. Plumb bob
PIPE WRENCH
A pipe wrench is used for holding and turning the pipes, rods and machine parts. Wrenches
are classified as follows.1.Fixed wrenches 2. Adjustable wrenches.

PIPE VICE
A pipe vice is fitted on the work bench. This has a set of jaws to grip the pipe and prevent
it from turning while cutting, threading and fitting of bends, couplings etc. The yoke vice is
commonly used in plumbing used in plumbingpractice.
 PIPE CUTTER

The pipe cutter mainly consists of three wheels which are hardened with sharp cutting
edges along their periphery. Of these three wheels, one can be adjusted to any desired distance to
accommodate different size of pipes. After adjusting the cutter on a pipe, it is around the pipe, so that
the cutter wheels cut the pipe along a circle as shown in fig.

HACK SAW

A hacksaw is used for cutting metal rods, bars, pipes, etc

THREADING DIES AND TAPS

It is used for cutting external thread on pipes. Threads are produced in various shape and
sizes which are used for fitting inside ahandle
FILES AND RASPS
The file surface is covered with sharp edged teeth and its used for removing metal by
rubbing. A rasp is used for finishing the surface of the work piece.

PIPE FITTINGS
Pipe fittings are made up of wrought iron. The size of pipe fitting is designated by the size
of the pipe on which it fits. Some of the common pipe fittings are shown in fig.

COUPLING

It is a short a cylindrical sleeve with internal threads throughout. A coupling is used for joining
two pipes in a straight and bend where at least one pipe can be turned.

PLUMB BOB

It is used for check the vertical line and made up of steel orbrass.

UNION
A union is used for joining two pieces of pipes, where either can be turned. It consists of
three parts, two parts joint can be screwed, in to two pipe ends, and the third on for tightening called
centrepart.

NIPPLE
A nipple is a short piece of pipe with external threads at both ends. It is used to make up the
required length of a pipe line.

ELBOW
An elbow is to make an angle between adjacent pipes.
TEE
A tee is a fitting that has one side outlet at a right angle to the run. It is used for a
single outlet branch pipe.

REDUCER
It is used to connect two different sized of pipes
PLUG

It is used to screw on to a threaded opening, for closing it temporarily.

VALVES
Valves are used for regulating the flow of fluid through a pipe. The
commonly used valves in plumbing’s are

1.Gatevalve 2.Globevalve
3.Plugvalve 4.Checkvalve 5. Air reliefvalve.

TYPES OF PIPE JOINTS

BELL AND SPIGOTJOINTS

A connection between two sections of pipe i.e. the straight spigot end of one section
isinserted into the flared out end of the adjoining section. The joint is sealed by a sealing component.
FLANGED JOINTS
A flanged joint helps to connect and disconnect two pipes as per the need. A similar
example is as shown in fig.

BOLTED JOINTS

The use of bolted joint is advantageous in the following circumstances

1. The component that cannot be serviced inline.

2. The components being joined that are not capable of beingwelded.

3. Quick field assembly isrequired.

4. The component or pipe section that needs to be frequently removed forsurface.

THREADED JOINTS

Threads are cutted in a pipe, flange coupling to connect them with each other and these
joints are called threaded joints.

FLEXIBLE JOINTS

The flexible joints are generally used to connect between a washbasin and an angle
valve.
SWING JOINTS
Swing joints are special purpose joints mainly used for industrial oriented purposes where
a long bend is required.

WELDED AND BRAZED JOINTS

Welded and brazed joints are the most commonly used joints for joining pipe
components.
EXPANSION JOINTS
Expansions joints are specially designed in pipeline where a small extension of pipe is required.

SINGLE LINE DIAGRAM

Single line diagram are most commonly used in plumbing diagram. All power plants and
bottling plant pipes are made by the single line piping diagram.
DOUBLE LINE DIAGRAM

It is used for catalogs and other applications where the visual appearance is more important.
EX.NO: PLUMBING OF ONE TAP WATER DISTRIBUTION SYSTEM
DATE:

AIM
To construct the one tape water distribution system by using plumbing components.

FITTINGS REQUIRED
1. PVCpipes

2. Tankfitting(GI)

3. Union(GI)

4. MTA(PVC)

5. Gatevalve

6. Elbow

7. Reducer(GI)

8. Bend(PVC)

9. FTA(PVC)

10. TAP(PVC)
PROCEDURE
1. The given PVC pipes are measured out to the required size.

2. The suitable die is selected.

3. Gate valve is connected between the two MTA.

4. 1” x ¾” reducer connected between 1” pipe and ¾”pipe.

5. 1” (GI) bend is connected between the two pipes.

6. ¾”x1/2” reducer connected between ¾” pipe and½”.

7. ½” bend connected between ¾” and ½”pipe.

8. At the end of the pipe ½” MTA tap isconnected.

RESULT
EX.NO: PLUMBING OF FOUR TAP WATER DISTRIBUTION SYSTEM

DATE:

AIM
To construct the one tape water distribution system by using plumbing components.

FITTINGS REQUIRED
1. PVCpipes

2. Tankfitting(GI)

3. Union(GI)

4. MTA(PVC)

5. Gatevalve

6. Elbow

7. Reducer(GI)

8. Bend(PVC)

9. FTA(PVC)

10. TAP(PVC)

PROCEDURE
1. The given PVC pipes are measured out to the requiredsize.

2. The suitable die isselected.

3. Gate valve is connected between the twoMTA.

4. 1” x ¾” reducer connected between 1” pipe and ¾”pipe.

5. 1” (GI) bend is connected between the twopipes.

6. ¾”x1/2” reducer connected between ¾” pipe and½”.

7. ½” bend connected between ¾” and ½”pipe.

8. Finally FTA ½” connected at four ends and then ½” tap fixed to the fourends.

RESULT
 CARPENTRY

INTRODUCTION
Carpentry may be designed as the process of making wooden articles and components such as
roots, floors, partitions, doors and windows. Carpentry involves cutting, shaping and fastening wood
and other materials together to produce a finished product. Preparation of joints is one of the
important operations in wood work.Joineny denotes connecting the wooden parts using different
points such as lap joints, mortise and tenon joints, bridle joints, etc.
CARPENTRY TOOLS
Carpentry tools are used to produce components to an
exact size. The types of carpentry tools are as follows.
1.Markingtools 2.Measuringtools 3. Holdingtools
4.Cuttingtools 5.Planningtools 6.Boringtools
7.Strikingtools 8.Miscellaneoustools
MARKING TOOLS
It is used to marking lines parallel to the edges of a wooden piece. It consists of a square
wooden stem with a sliding wooden stock on it. On the stem, a marking pin is attached which is
made up of steel. This stem is provided with a steel nail to scratch the surface of the work. It consists
of two pins; the distance between the pins is adjustable. It is used to draw parallel lines on thestock.

MEASURING TOOLS
The carpentry measuring tools are classified as follows
1.SteelTap 2.Steelrule 3.Calipers

Steel tapes and steel rules are mainly used for measuring short and lengths in millimeters.

A try square is used for testing squareness and marking of joints.

A mitre square is used for marking and measuring an angle of 45 °.
A bevel square is used for marking and listing angles between 0° to 180°
Calipers are used for the precision measurement of cylindrical surface. Inside calipers are used for
measuring outside diameter and outside calipers are used to measure inner diameter ofa pipe.

HOLDING TOOLS

The carpentry holding tools are shown in fig.

CARPENTRY VICE
A carpentry vice is the common work holding device. It consists of one fixed jaw and one
movable jaw. Its one jaw is fixed to the side of the table while the other is movable by means of a
screw and a handle.

BAR CLAMP

The bar clamp (or) sash cramps are generally used in pairs in glueing up operations at the
final assembly of joinery work. It is made up of a steel bar of T-section, wine malleable iron fittings
and a steel screw.

G-CRAMP

G-cramp is made up of malleable iron with acme threads of high quality steel .It can be used
for clamping small work when glueing up.
CUTTING TOOLS
SAWS
A saw is used to cut wood into pieces. There is different type of saws, designed to suit
different purpose. A saw is specified by the length of its tooled edge. The following saws are used in
the carpentry section.
RIP SAW
The blade of rip saw is either straight or skew-backed. The teeth are so set that the cutting

edge of this saw makes a steeper angle about 60°.

CROSS CUT SAW

This is similar in shape of a rip saw. It is used to cut across the grain of the stock. The correct

angle for cross cutting is 45°.The teeth are so set that the saw kerf is wider than the blade thickness.
This allows the blade to move freely in the cut without sticking.

TENON OR BACK SAW

A tenon saw is used for fine and accurate work. It consists of a very fine blade, which is
reinforced with a rigid steel back. The teeth are shaped like those of cross cut saw.
CHISELS

Chisels are used for cutting and shaping wood accurately. Wood chisels are made in various
blade widths, ranging from 3 to 50mm .Most of the wood chisels are made into tang type, having a
steel shank which fits inside thehandle.

FIRMER CHISELS

These are general purpose chisels and are used either by hand pressure or by a mallet. The

blade of a firmer chisel is flat and their sloping face is at an angle 15° to 52° .

MORTISE CHISELS
These are general purpose chisels and are used for cutting mortises above 9 mm wide.The blade of a
firmer type in which they have a thicker section and a stronger neck. By means of this chisel we can
apply more Leverage to remove waste wood from the mortise.

BEVEL CHISELS

A bevel chisel is similar in construction to the firmer chisel. Its edges are bevelled to allow
access to difficult corners. It has a blade with a bevelled back due to which it can enter sharp corners
for finishing in dovetail joints.

PLANNING TOOLS

In general, planes are used to produce flat surfaces on wood. The cutting blade used in a
place is very similar to a chisel. The blade of a plane is fitted in a wood or metallic block at an angle.
 Jack plane which is about 35 cm long is used for general planning. A smooth plane that is about
20 to 25cm long is used for smoothening the stock .Being short; it can follow even the slight
depressions in the stock better than the jack plane. Smooth plane is used after using the jack plane.

A rebate plane is used for making a rebate .A rebate is a recess along the edge of a piece of wood
which to generally used for positioning glass in frames and doors. A plough plane is used to cut
grooves, which are used to fix handle in a door.

BORING TOOLS
Boring tools are used to make holes in wood .Common types of boring tools are as follows.

1. bradawl

2. Gimlet

3. Brace

4. Bit anddrill
A brace bolds and turns the bit and boring of a hole is obtained. A brace having two jaws
is used for holing the bit in one end. It has two types, namely ratchet brace and wheel brace.A
bradawl and a gimlet are used for boring small holes. These tools are hand operated.
STRIKING TOOLS

HAMMERS
The cross peen hammer is mostly used for positioning small nails. The head is tightly held in
the handle with the help of iron wedges. The claw hammer is effective in removing very large nails
and also for driving the nails using the other end of the hammer.

MALLET
A mallet is used to drive the chisel, when considerable force is to be applied, which may be
the case in making deep rough cuts. A steel hammer should not be used for this purpose, as it may
damage the chisel.

RASP FILE

A rasp file is shown in Fig. rasp is a file used for finishing the surface of wood. The rasp
has sharp cutting teeth on its surface for this purpose. The file is used for removing rasp marks end
finally the scratches left by the fix are removedwith the scraper and glass paper.
OIL STONE
This is an essential flat used for providing sharp edges on cutting tools. The oil stones
may be artificial or natural stones. The carborundum is the best artificial stones where as the
Arkansas are the natural stones.

MISCELLANEOUS TOOLS

SPIRIT LEVEL

The spirit level is used to check the level of the wooden surface. A narrow glass tube is
fitted into a small rectangular wooden box. The glass tube contains spirit and bubble. On placing
the spirit level if bubble stays in the middle, then the surface is flat otherwise it is having a slope.

PINCERS
They are made up of steel with a hinged joint and are used for pulling out small nails
from wood.

SCREWDRIVERS
Screwdriver is used for driving wood screws into wood or unscrewing them. The
screwdriver used in carpentry is different form the other common types.

CAPPENTRY MACHINES
Carpentry machines are used for large production of components. The commonly used
carpentry machines are described below.
WOOD TURNING LATHE
A wood turning lathe is the most important machines used in a carpentry shop. It is used
for producing cylindrical, spherical and tapered shape products.

A wood working lathe consists of a cost iron body, main motor, cone pulley system, spindle,
tool post, head stock, live and dead centers and speed control devices. In wood working lathes, the
workpiece is held between the two centers. The tool is held in the tool post. The workpiece is
rotated in between the two centers whereas the cutting tool passes towards the work and removes
the material and produces the desired shape and size.
CIRCULAR SAW
A circular saw is used for ripping, cross cutting, leveling, grooving and rebating,. It consists
of a cast iron table, a circular cutting blade, guide ways, saw guide, elevating hand wheel, tilting
handwheel,and a main motor.In circular saws, the workpiece is held on the table. Then the work is
moved against the circular saw to perform the operations. The saw hand wheel is used to adjust the

height of the saw above the surface of the table.The table can be tilted up to 450 for cutting with
different angles. It is an ideal machine. The size of the saw depends upon the size of the saw blade.
BAND SAW
A band saw is used for cross cutting, leveling, mitering, grooving and rebating. It consists of
two wheels having an equal diameter, saw guider, frame table, wheel guard, saw tension,
arrangement and steel blade having teeth on it. The saw blade travels over the rims of two wheels.
The blade width varies from 6 to 25 mm and the thickness is about 1 to 2 mm.
CARPENTRY PROCESSES
In a carpentry shop, a number of operations are performed to get the finished workpiece.
The different types of process performed in a carpentry shop can be classified asfollows.
MARKING AND MEASURING
It is the process of setting of dimensions on wooden pieces to obtain the required shape.
This is the first step for further carpentry operations. The marking operation is done with use of
marking tools. Before marking, one end is planed forreference.
SAWING
Sawing is the process of cutting wood to the required shape and size such as straight,
inclined or curved. Sawing can be done along the grains or across the grains.In sawing, wooden
work is fixed in a vice and wood is moved up to prevent vibrations during sawing.

PLANING
Planing is an operation of obtaining, smooth, dimensionally true surface of wood by using a
planer. It is done along the grains. So; smooth surface is achieved. This process can be also called
facing oredging.
CHISELING

It is the process of cutting a small stock of wood to produce required shapes.

MORTISING AND TENONING

Mortising is the process of producing a mortise, i.e. a rectangular or square holes and recesses
in wooden pieces. A tenon is a projected piece of wood that fits into the corresponding mortise. This
process is done by using mortise chisels and a mallet.
BORING
Boring is the process of producing through holes or blind holes in wooden piece. This process
can be done straight or inclined according to the type of work. The small holes are produced by using
bradawl and gimlet, whereas large holes are produced by using braces, drills.
GROOVING

Grooving is the process of making grooves tonguing is the process of producing

corresponding projections of wood for fitting into grooves. Grooving and tonguing operation can be
seen in drawing boards, floor boards and partitions. Grooving is done with a plough plane tool, and
tonguing is done with a moulding plane tool.
EX.NO: T-JOINT

DATE:

AIM

To make the T-joint the required dimensions from the given work piece.

MATERIAL REQUIRED Soft wood of size 300x50x50 mm.

TOOLS REQUIRED

1. Jackplane
2. Carpentry vice
3. Trysquare
4. Markinggauge
5. Steelrule
6. Tenon saw
7. Ripsaw
8. Firmerchisel
9. Mallet

PROCEDURE

1. The given workpiece is firmly clamped in the carpentry vice and any two adjacent surfaces
are planed to get right angles using the jackplane.
2. Using the try square, the right angles of planned faces arechecked.
3. Now the other two surfaces are planned to get smoothsurface.
4. The workpiece is cut into two pieces by using the ripsaw.
5. Using the steel rule and marking gauge, marking is donefor T-joint on the two halves.
6. In one half, the unwanted portions of wood are removed by using the tenon saw and
firmer chisel. The same procedure is done for the other half ofworkpiece.
7. Using the jack plane, the other two faces of workpieceis planned to the requiredsize.
8. The finished two pieces are assembled to getter to form theT-joint.
9. Finally, the finished job is checked for required size and shape using the steel rule and try
square.
RESULT
EX.NO: DOVE TAIL JOINT

DATE:

AIM

To make the Dovetail joint the required dimensions from the given work piece.

MATERIAL REQUIRED

Soft wood of size 300x50x50 mm.

TOOLS REQUIRED

1. Jackplane
2. Carpentry vice
3. Trysquare
4. Mortisegauge
5. Mallet
6. Firmer chiesel

PROCEDURE

1. The given work piece is firmly clamped in the carpentry vice and any two adjacent
surfaces are planed to get right angles using the jackplane.
2. Using the try square, the right angles of planned faces arechecked.
3. Now the other two surfaces are planned to get smoothsurface.
4. The work piece is cut into two pieces by using the ripsaw.
5. Mark the dimensions for the dovetail joint on the two pieces using the steel rule and
markinggauge.
6. Remove the unwanted portions as per the drawing and assemble to
check proper fitting.
RESULT
 WELDING

INTRODUCTION
Welding is metal joining process wherein localized coalescence is produced either by
heating the metal to a suitable temperature, with or without the use of filler metal, with or without
application of pressure. The filler material has similar composition and melting point temperature as
that of the base metal. It is used to fill gap between the joint surfaces.

TYPES OF WELDING
The welding process is divided into two main sub divisions.
PLASTIC WELDING
The pieces of metal to be joined are heated to the plastic state and then forced together
by external pressure without the addition of filler material.

FORGE WELDING
The work piece are placed in a forge or other appropriate furnace and heated within the area
to be joined to the plastic condition. Then parts are quickly superimposed and worked into a
complete union by hand or power hammering or by pressingtogether.

RESISTANCE WELDING
In resistance welding, a heavy electric current is passed through the metals to be joined over
limited area, causing them to be locally heated to plastic state and the welding is completed by the
application of pressure for the prescribed period of time.

FUSION WELDING
In fusion welding, the metal parts to be joined are melted and then allowed to solidify
pressure is not applied and filler metals may be used for this type of welding.

GAS WELDING
Gas welding is a process in which the required heat to melt the surfaces is supplied by a high
temperature flame obtained by a mixture of two gases. Usually the mixture of oxygen and acetylene
is used for welding purpose.
ELECTRIC ARC WELDING

Electric arc welding is the process of joining two parts by melting their edges by an electric
arc with or without the application of pressure and with or without use of filler metals.

THERMIT WELDING
Thermit welding is a fusion process in which weld is effected by pouring super heated liquid
thermit steel, around the parts to be united with or without the application of pressure.

OXY-ACETYLENE WELDING
 In oxy-acetylene welding oxygen and acetylene are the two gases used for producing
flame. Oxygen is mainly used for supporting the combustion intensity.

The oxygen and acetylene under high pressure in cylinders which are fitted with pressure
regulator. Each cylinder is connected to the blowpipe by flexible hoses. The oxygen cylinders are
painted block and acetylene cylinders are painted maroon.

When acetylene is mixed with oxygen in correct proportions in the welding torch, ignition is
takes place. The flame resulting at the tip of the torch is sufficient enough to melt and the parent
material .The flame temperature is about 3200ºC.The filler metal rod is generally added to the molten
metal pool to built up the seam for greater strength.
TYPES OF FLAMES
1 .Neutral Flame (Oxygen, Acetylene in equal proportions)
2. Oxidizing Flame (excess ofOxygen)
3. Reducing Flame (excess ofAcetylene)
NEUTRAL FLAME

A neutral flame is produced when approximately equal volumes of oxygen and acetylene are
mixed in the welding torch and burnt at the torch tip.
The temperature of the neutral flame is of the order of about 3260ºC
The flame has inner cone which is light blue in color.
The neutral flame is used for welding of mild steel, copper, aluminum, cast iron, etc.
OXIDIZING FLAME
If the volume of the oxygen supplied to the neutral flame is increased, then resulting flame
will be oxidizing flame.
The temperature of oxidizing flame is of the order of about 3482ºC.
Normally the outer flame envelope is much shorter. It has very small white inner
cone. This flame is used to weld copper-base metals, zinc-base metals.
Reducing Flame (Carburizing Flame)

If the volume of the oxygen supplied to the neutral flame is reduced, the resulting flame.In this
case, flame is recognized by acetylene feather which exists between the inner cone and outer
envelope. The outer flame envelope is longer than that of the neutral flame and is usually much
brighter in color. It has an appropriate temperature of 3038ºC.In this type, flames are used to weld the
high-carbon steel, non-ferrous alloys, zinc- bearingalloys.

FLAME
ADJUSTMENT
NEUTRALFLAME

To get the neutral flame, add sufficient oxygen to make the white cone clear and round.
During the neutral flame, the gas mixture from the blow pipe consists of oxygen and
acetylene in the ratio of 1:1:1
OXIDIZING FLAME
To get the oxidizing flames add, more
oxygen. The white cone will becomes
short andsharp.
The flame will produce a hissing sound and will have a short length.
CARBURIZING FLAME
To get the carburizing flame adds more acetylene to the neutral flame.The white cone will
become long surrounded by a feather-like portion. Flame will burn quietly and have more
length.

FILLER METAL
It is the material that is added to the weld pool to assist in filling the gap. Filler metal
forms an integral part of the weld. The filler metal is usually available in rod form. The rods are
called filler rods.

FLUXES
During the welding, if the metal is heated in the air, oxygen in the air combines with the metal
5 to form oxides which result in poor quality, low strength welds or in some cases may even make
welding impossible. In order to avoid this problem, a flux is added during the welding. The flux
prevents oxidation by preventing oxygen from contacting the weld zone. No flux is used in the gas
welding of steel. The most commonly used flux materials are boric acid, soda ash and sodium
chloride.

ARC WELDING
In the arc welding process, the source of heat is electricity. In arc welding process,
coalescence is produced by heating the work piece with an electric arc struck between electrode and
the work piece. Welding may be carried out in air or in an inert atm. Filler material may or may not
be used. The temperature of the arc is of the order of 3600ºC.

PRINCIPLE OF ARC WELDING:

PRINCIPLE OF OPERATION

The heat required for joining the metals is obtained from an electric arc. The electric motor
generator or transformer sets are used to supply high electric current and the electrodes are used to
produce the necessary arc. The electrode serves as the filler rod and arc melts the surfaces so that the
metals to be joined are fusedtogether.The transformer type welding machine produces AC current. It
takes power directly
Comparison of A.C and D.C arc welding equipments

No Alternating current (AC) Direct current (DC)

1 It is not suitable for joining non-ferrous It is not suitable for both ferrous
metals. and non-ferrous metals.

2 Only coated electrodes can be used. Bare electrodes can also be used.

3 Consumes less power. Consumes more power.

4 High efficiency. Low efficiency.

5 Cost of equipment is less. Cost of equipment is more.

6 Noiseless operation. It gives noise.

7 Not suitable for welding thin sections. Suitable for welding thin sections.
ELECTRODES

Filler rods are used in arc welding are called as electrodes. The Electrodes are made of
metallic wire called core wire. It is uniformly with a protective coating called flux while fluxing an
electrode about 20 mm of length is left bare at one end for holding it using electrode holder. It is
used to transmit full current from electrode holder to the front end ofthe electrode coating.
ELECTRODE HOLDER

It is a device used for mechanically holing th electrode and conducting current toit.

Electrode holder should be light, to minimize fatigue incurred by the welder.

Jaws are made to hold the bare end of the electrode in either at vertical or at an
angularposition.
WELDING CABLES
Two cables are needed for welding purpose. One is used to connect the power
source to electrode; another cable is connected toground.The cables are well
isolated withrubber.

WELDING BEAD CLEANING ACCESSORIES

CHIPPING HAMMER
A chipping hammer is chisel-shaped one and it is used to remove the slag from the weld bead
HAND GLOVES
Hand gloves are used to protect the hands from electrical shock, arc radiation and
hot spatters.

ADVANTAGES OF ARC WELDING

Flux shielded manual metal arc welding is the simplest of all the arc weldingprocess.

The equipment can be portable and the cost is fairlylow.

This process finds innumerable applications, because of the availability of a wide variety
of electrodes.
A big range of metals and their alloys can bewelded.

Disadvantages of arc welding

Because of the limited length of each electrode and brittle flux coating onit,
Mechanization is difficult.

In welding long joints, as one electrode finishes, the weld is to be progressed with the next
electrode. Unless properly cared, a defect may occur at the place where welding is restarted with
the newelectrode.
It cannot be used to weld metal thickness less then 1.6mm.
EX.NO: LAP JOINT

DATE:

AIM
To join the given two work pieces as a lap joint by arc welding.

MATERIAL USED
Mild Steel plates.
TOOLS REQUIRED
1.Weldingpowersupply 6.Flatfile
2.Weldingrod 7.Chipping hammer
3.Electrodeholder 8.Wirebrush
4.Glovesandapron 9.Earthing clamps
5.Shield andgoggles
PROCEDURE
1. First of all, the work pieces must be thoroughly cleaned to remove rust, scale and other
foreignmaterials.
2. Then the given work pieces are placed on the table in such a way that one work piece
is placed on the other work piece like the LAP joint isformed.
3. Appropriate power supply should be given to the electrode and the workpieces.

4. Now the welding current output may beadjusted.

5. When current is passed, arc is produced between the electrode andwork pieces.

6. Then the welding is carried out throughout thelength.

7. As soon as the welding process is finished, switch off the current supply and allow the
work piece tocool.
8. Slag is removed by chipping process with the help of chippinghammer.

9. Finally using wire brush, welded portions arecleaned.

RESULT
EX.NO: SINGLE V BUTT JOINT
DATE:

AIM
To join the given two work pieces as a single ‘v’ butt joint by arc
welding.
MATERIAL USED
Mild Steel plates.

TOOLS REQUIRED
1.Weldingpowersupply 6.Flatfile
2.Weldingrod 7.Chipping hammer
3.Electrodeholder 8.Wirebrush
4.Glovesandapron 9.Earthing clamps
5.Shield andgoggles

PROCEDURE
1. First of all, the work pieces must be thoroughly cleaned to remove rust, scale and other
foreignmaterials.
2. Then the given work pieces are placed on the table in such a way that work pieces are
brought close to close to each other so that it forms a V shapes when the plates butt each
other.
3. Appropriate power supply should be given to the electrode and the workpieces.

4. Now the welding current output may beadjusted.

5. When current is passed, arc is produced between the electrode andwork pieces.

6. Now set the two work pieces in correct position and maintain the gap 3mm and tag at
both ends of the work pieces as shown infigure.
7. Then the welding is carried out throughout thelength.

8. As soon as the welding process is finished, switch off the current supply and allow the
work piece tocool.
9. Slag is removed by chipping process with the help of chippinghammer.
 10. Finally using wire brush, welded portions arecleaned.
RESULT
EXNO. T-JOINT
DATE:

AIM

To join the given two work pieces as a ‘T’ joint by arc welding

MATERIAL USED

Mild Steel plates.

TOOLS REQUIRED
1.Weldingpowersupply
2.Weldingrod
3.Chipping hammer
4.Electrodeholder
5.Glovesandapron
6.Flatfile
7.Wirebrush
8.Earthing clamps
PROCEDURE
1. First of all, the work pieces must be thoroughly cleaned to remove rust, scale and other
foreignmaterials.
2. Now the work pieces are placed on the table in such a way that two work pieces are abroad
close to each other T shapes are formed as shown infigure.
3. Appropriate power supply should be given to the electrode and the workpieces.
4. Now the welding current output may beadjusted.
5. When current is passed, arc is produced between the electrode andwork pieces.
6. Now set the two work pieces in correct position like T joint and tag at both ends of the work
pieces as shown infigure.
7. The joint is placed on a welding table in a flat position by keeping the tag sidedown.
8. Then the welding is carried out throughout the workpiece.
9. As soon as the welding process is finished, switch off the current supply and allow the work
piece to cool.
10. Slag is removed by chipping process with the help of chipping hammer.
 11. Finally using wire brush, welded portions are cleaned.

RESULT
 STUDY OF LATHE

AIM
To study about the lathe

INTRODUCTION
Lathe is called the father of machine tools. The main function of lathe is to remove
metals from work piece to give a required shape and size. In the lathe the work piece is held in a
chuck. The tool is moved at an angle 90_ to the axis. Various operations such as straight turning,
taper turning, and chamfering, facing, knurling, grooving, thread cutting, taper turning are
carried out. When the operations above set are done automatically, then the lathe is called
automatic lathe.

WORKING PRINCIPLE OF LATHE

In a lathe, the work piece is held in chuck and rotates about its axis by means of power. A
single point cutting tool is mounted in tool post. When the chuck rotated the work piece also
rotated. The tool moves parallel to the axis of rotation of work piece to produce a cylindrical
surface, where as the tool moves perpendicular to the work piece to produce a flat surface. The
tool moves at an angle to the axis of work piece to produce a turn surface. The material is
removed in theform of chip from the work piece by giving proper feed and depth of cut. So,
there quire size and shape of the work isobtained.
MAIN PARTS OF LATHE
The lathe consists of various parts. Their parts and function are discussed below.
BED
Bed is the base of the lathe. The headstock is mounted on the left end; the carriage is in
the middle and the tailstock at the right end of bed. The bed is made up of cast iron, alloyed with
nickel, chromium. The bed is made up of cast iron to observe shock and vibration created during
machining. The guide ways of the bed may be flatter inverted ‘V’ shape.
HEADSTOCK
It is mounted on the left end of the bed. It carries a hollow spindle. The live center can be
attached in the spindle. The spindle nose is threaded. In chuck faceplates can be attached to the
spindle. The headstock may be back threaded type. The headstock has two types of driving
 mechanism
Back geared mechanism
Belt driven mechanism
TAILSTOCK
It is located on the bed at the right end. It is used for supports right end of work and also for
holding drills, reamer tools for drilling, reaming and such other operations. The tailstock can be
moved along the bed and clamped at any position, to support the different lengthwork.

CARRIAGE
Carriage is used for giving various feed to the tool by hand or by power. The carriage is
attached with the saddle.
SADDLE
It is a H shaped casting fitted on the bed and moves along the guide ways. It carries the cross
slide, compound rest and a tool post.
i) Crossslide
It is attached to the upper side of saddle and carries compound slide and tool post. The cross slide
can be moved cross wise by hand or power. The micrometer dial is mounted on the cross slide hand
wheel, with an accuracy of 0.05mm.
ii) CompoundRest
It is attached over the cross slide. It is used during the taper turning opening operations to set the tool
for angular cuts. Here the micrometer dial is mounted to show the depth ofcut.
iii) Toolpost
The tool is clamped over the tool post. It is fixed over the compound rest. There are four types of tool
post
a. Single screw toolpost
b. Open side toolpost
c. Four bolt toolpost
d. Four way toolpost
APRON
Apron is attached to the saddle and hangs in front of the bed. It has gears, levers, clutches for
moving the carriage automatically. A split nut is attached for engaging and disengaging the
carriage from the lead screw. It is used in thread cutting work.
LEAD SCREW
It is a longer screw with standard ACME square threads and used for transmitting power for
automatic feed for thread cutting operation.

FEED ROD
The feed rod is the long shaft used for the movement of carriage along the axis of bed. Itis used
for operations like facing, turning and boring.

RESULT
Thus the lathe was studied.
EXNO: FACING, PLAIN TURNING AND CHAMFERING

DATE:

AIM

To perform turning, facing and chamfering on a cylindrical work piece.

MATERIAL USED Mild steel rod.

TOOLS REQUIRED
1. Lathe
2. Three-jawchuck
3. Chuckkey
4. Vernier caliper
5. Single-point cuttingtool

PROCEDURE
1. First loosen the jaw in the chuck key to position the work piece, and then tighten the Jaws.
2. Fix the cutting tool in the toolpost.
3. Switch on the lathe and move the carriage near to the work piece. Give it a small cross feed,
and then move carriage longitudinally to the required length slowly.
4. Bring the carriage to the original position, give a small cross feed and move carriage
Longitudinally. Repeat this step until required diameter isobtained.
5. To get smooth surface give a very small feed when the diameter is nearing the requiredvalue.
6. To face the end surface of the work piece, move the carriage to make the tool touch the end
surface of the workpiece.
7. Give a small feed in longitudinal direction, and then move the tool towards the axis of the
work piece using the cross slide to complete the workpiece.
8. Using the proper drill pit to the required length make a blindhole.

RESULT
EXNO: FACING, PLAIN TURNING AND TAPER TURNING

Date:
AIM
To perform turning, facing and chamfering on a cylindrical work piece.
MATERIAL USED Mild steel
rod.
TOOLS REQUIRED
1. Lathe
2. Three-jawchuck
3. Chuckkey
4. Vernier caliper
5. Single-point cuttingtool
PROCEDURE
1. First loosen the jaw in the chuck key to position the work piece, and then tighten the Jaws.
2. Fix the cutting tool in the toolpost.
3. Switch on the lathe and move the carriage near to the work piece. Give it a small cross feed,
and then move carriage longitudinally to the required lengthslowly.
4. Bring the carriage to the original position, give a small cross feed and move carriage
Longitudinally. Repeat this step until required diameter isobtained.
5. To get smooth surface give a very small feed when the diameter is nearing the requiredvalue.
6. To face the end surface of the work piece, move the carriage to make the tool touch the end
surface of the workpiece.
7. Give a small feed in longitudinal direction, and then move the tool towards the axis of the
work piece using the cross slide to complete the workpiece.
8. The turning operation is done with cutting tool to reduce the diameter up to the required
dimension for the two steps of variousdiameters.
9. The work piece is removed from the chuck and the dimensions of
work piece are checked for therequirements.
RESULT:
EX.NO: DRILLING AND TAPPING

Date:
AIM
To make an internal thread on a given work piece as per the required dimensions
using drilling machine and tapping tool.

TOOLS REQUIRED
1. Machinevice 2. Drillingmachine
3.Drillbit 4. Tappingtool
5.Dot punch 6. Hammer etc.
PROCEDURE
1. The dimensions of the given work piece is checked as per therequirement.

2. The work piece is clamped in the vice and any two surfaces are filed to get rightangle.

3. Drill bit of required size is fitted in the drill chuck of the drillingmachine.

4. The mid point of the required hole is punched by using dot punch andhammer.

5. The punched dot is drilled by drillingmachine.

6. After drilling the hole, they are tapped by using taptool.

7. Finally the dimensions are checked.

RESULT
EX.NO: DATE:

MACHINING A WORK PIECE BY STEP TURNING OPERATIONS USING A LATHE

AIM
To machine a work piece by facing, plain turning and step turning operations using a lathe.

MATERIALS REQUIRED
Mild steel polished round rod -  25 X 75 mm

TOOLS REQUIRED
1. Lathe machine
2. Cutting tool
3. outside Caliper
4. Steel Rule
5. Vernier Caliper

PROCEDURE
1. The given work piece is held firmly in a lathe chuck.

2. The cutting tool is set in a tool post such that the point of the cutting tool coincides with the
lathe axis.

3. The machine is switched on to revolve the work piece at the selected speed.

4. By giving Cross feed and longitudinal feed to the cutting tool, the facing and turning
operations are done respectively.

5. The machine is switched off.

6. The work piece is removed from the chuck and all the dimensions are measured and checked.
 BEFORE MACHINING

Fig (1)

AFTER MACHINING

Fig (2)

ALL DIMENSIONSARE IN mm

RESULT
EX.NO DATE:

MACHINING A WORK PIECE BY BORING AND INTERNAL THREAD CUTTING

OPERATIONS USING A LATHE

AIM
To machine a work piece by facing, plain turning, boring and internal thread cutting operations
using a lathe.

MATERIALS REQUIRED
Mild steel polished round rod -  25 X 75 mm

TOOLS REQUIRED

1. Lathe machine 5.Outside Caliper

2. Turning tool 6.Steel Rule

3. Boring tool 7.Vernier Caliper

4. Internal V – thread cutting tool

CALCULATION:

The number of teeth on change gears is calculated using the following

formula: Driver teeth/ Driven teeth = Pitch of the work / pitch of the lead
screw.
PROCEDURE:

1. The given work piece is held firmly in a lathe chuck.

2. The cutting tool is set in a tool post such that the point of the Cutting tool coincides with
the lathe axis.
3. The machine is switched on to revolve the work piece at the selected speed.
4. By giving Cross feed and longitudinal feed to the cutting tool, the facing and turning operations
are done respectively.
5. The speed of the work piece is reduced.
6. The boring operation is done using boring tool.
7. The machine is switched off and the change gears of calculated teeth(as per calculation) are
connected.
8. Again the machine is switched on.

9. The internal thread cutting operation is done using internal V–thread cutting tool by engaging
thread cutting mechanism.
10. The machine is switched off.
11. The work piece is removed from the chuck and all the Dimensions are measured and checked.

BEFORE MACHINING

Fig (1)

AFTER MACHINING

Fig (2)

ALL DIMENSIONSARE IN mm
 SHEET METAL
INTRODUCTION

Sheet metal works deals with working on the metal of 16-30 gauge ,with hand tools and
simple Machines. It is one of the major applications in engineering industry. It has its own
significance as useful trade in engineering work. Sheet works such as making a tray, box , funnel,
chimney, air duct, fabricate boiler shells and pipe joints from thin or thick plates, etc. are few
examples of its application. For successful working in the trade, one should have a thorough
knowledge of projective geometry and development ofsurfaces.
SHEET METAL TOOLS

STEELRULE

It is used to measure and mark dimensions. It is graduated on both sidesin

millimetersand centimeters or inches.
DIVIDER
It is used in sheet metal jobs for circle making. With the dividerwe can
also do making the parts of thejob.

STEEL SQUARE

It is used for checking the right angle of the jobs.

TRAMMEL
It is used to draw large circles and arcs. This is also a marking tool
WIRE GAUGE
The thickness of sheet metal is referred in numbers known as Standard Wire
Gauge (SWG). The gaps in the circumference of the gauge are used to check the gaugenumber
BENCH SHEAR
Sheet metal may be cut by shearing action. In this, the force is applied through a compound
lever, making it possible to cut sheet metal up to 4 mmthick.

SNIPS
This tool is used for cutting thin metal sheets, before or after marking, according to the
jobs,
is called snips. The straight snip is used for cutting along outside curves and straight lines and
curved snip or bent snip is for trimming along inside curves.
 HAMMERS
Light weight hammers and mallets are used in sheet metal work. Ball- peen Hammer
has
a cylindrical slightly curved face and a ball head. It is a general purpose hammer used mostly for
riveting in sheet metal work. The cross-peen hammer and straight peen hammers are used for
folding the sheet and to work in the corners of theobject.

MALLET
Mallet is used for bending and folding work. It is called as soft hammer. Generally, it is made
of wood.

STAKES
Stakes are nothing but anvils, which are used as supporting tools and to form, seam,bend or
rivet, sheet metal objects. They are made from wrought iron, faced with steel.
SCRIBER
This tool is used for making sheet metal jobs.

PUNCH
Punch is used in sheet metal jobs for punching or deep marking.
EX.NO: SHEET METAL TRAY
DATE:

AIM
To make a rectangular tray from the given sheet metal.

MATERIAL REQUIRED
G.I Sheet
TOOLS REQUIRED
1. Steelrule
2. Mallet
3. Scriber
4. Divider
5. Protractor
6. Snips
7. Stakes
8. Ball peenhammer
PROCEDURE
1. The size of the given sheet is checked for its dimension using steelrule.
2. Then the sheet is leveled on the leveling plate using amallet.
3. The development procedure is followed the same as the square tapertray.
4. The dimensions are marked as shown infigure.
5. The sheet is cut as per the marked dimensions by straightsnips.
6. Then a single hemming is made on the four sides of the tray as shown infigure.
7. The four sides of the tray bent to 90_ using the stakesanvil.

8. Finally all the corners of the tray are joined byriveting.

RESULT
EX.NO: MAKING OF A FUNNEL

DATE:

AIM
To make a funnel from the given sheet metal.

TOOLS REQUIRED
1. Steelrule
2. Mallet
3. Scriber
4. Divider
5. Protractor
6. Snips
7. Stakes
8. Ball peen hammer
9. Solder
PROCEDURE
1. The size of the given sheet is checked for its dimension using steelrule.
2. The required development of surface is being made on the white paper which is overlapped on
the sheetmetal.
3. The marking is done on the sheet metal as per the development being done on the paper.
4. Now using straight snips, unwanted material areremoved.
5. Now fold and bend the workpiece to make the funnel shape and joint is made on the work
pieces.
6. Then using a groove, a locked grooved joint is made for about 5mm. also; hemming is done in
the bottom of thefunnel.
7. In between top face and bottom face, a butt joint is made using asolder.
8. Finally, trimming and finishing operations are carriedout.

RESULT
 FITTING

The term fitting, is related to assembly of parts, after bringing the dimension or shape to the
required size or form, in order to secure the necessary fit. The operations required for the same are
usually carried out on a work bench, hence the term bench work is also added with the name fitting.

The bench work and fitting plays an important role in engineering. Although in today's
industries most of the work is done by automatic machines which produces the jobs with good
accuracy but still it (job) requires some hand operations called fitting operations. The person working
in the fitting shop is called fitter

FITTING TOOLS:
Fitting shop tools are classified as below:
1. Work Holding Devices/ ClampingTools.
2. Measuring and MarkingTools.
3. CuttingTools.
4. StrikingTools.
5. DrillingTools.
6. ThreadingTools.
I. WORK HOLDING DEVICES /CLAMPINGTOOLS:

1. WorkBench

A fitting process can be done

at various places, but most of the
important operations of fitting are
generally carried out on a table
called workbench.The work bench is
a strong, heavy and rigid table made
up of hard wood.The size of the
work bench required is about 150 to
180 cm length, nearly 90 cm width
and approximately 76 to
84 cm height.
2. BENCH VICE:

It is firmly fixed to the bench with the help of nuts and bolts. It consists of a cast Iron body
and cast iron jaws. Two jaw plates are fitted on both the jaws. The holding surface of the jaw plates
is knurled in order to increase the gipping. Jaw plates are made up of carbon steel and are wear
resistant. One jaw is fixed to the body and the second slides on a square threaded screw with the
help of ahandle.

The jaws are opened up to required length; job is placed in the two jaws and is fully tightened with
the help of handle. Handle is used to move the movable jaw.

3. VBlock

In V Block, V grooves are provided to hold the round objects longitudinally. The screw
of the clamp applies the holding pressure. When the handle is rotated there is movement in the
screw.
II. MEASURINGTOOLS

1. Steel Rule
These are made up of stainless steel and are available in many sizes ranging from 1/2 ft. to 2 ft.
These are marked in inches or millimetres. All the faces are machined true. The edges of steel rule

should be protected from rough handling.

2. Calipers
These are generally used to measure the inside or outside diameters. Different types are:
i. Outside Caliper: It is used to measure the outside dimensions.
ii. Inside Caliper: It is used to measure the inside dimensions.
iii. Spring Caliper: Spring is provided to apply the pressure and lock nut is provided to lock any

desired position.
iv. Hermaphrodite, Jenny or Odd leg Caliper: One leg is bent at the tip inwardly and the

other has a straight pointed end. It is used to scribe lines parallel to the straightedges.
3. Vernier Caliper: It is used for measuring the outer dimensions of round, flat, square components
and also the inner size of the holes and bore. A narrow blade is used to measure the depth of bar
slots etc. The reading accuracy in metric system is 0.02 mm and British system it is 0.001”. It is
made of stainlesssteel

CROSS FILING
This method is used for efficient removal of maximum
amount of metal in the shortest possible time. It may be noted that
the file
must remain horizontal throughout the stroke (long,
slow and steady) with pressure only applied on the
forward motion.

DRAW FILING
This method is used to remove file marks and
for finishing operations. Here, the file is gripped as
close to the work as possible between two hands. In this
filing
method, a fine cut file with a flat
face should be used.
EX.NO: SQUARE CUTTING

DATE
AIM
To make a Square fit from the given mid steel pieces.

MATERIALS REQUIRED
Mild steel flat (40*40*3mm).

TOOLS AND EQUIPMENT REQUIRED:

1. 6”try square
2. 6”sriber

3. Odd leg
caliper

4. 12”hack
saw

5. Frame Blades (12TPI)

6. 10”roughfile

7. 10”smoothfile
8. 10”Squarefile

9. Dot punch
10. Ball peen hammer (0.5Ib).
11. Steel Rule

PROCEDURE
1. The given mild steel flat piece is checked for givendimensions.

2. One edge of given is filled to straightness with rough and smooth files and checked with
trysquare.
3. An adjacent is also filled such that is square to first edge and checked with trysquare.

4. Wet chalk is applied on one side of the flat and dried formaking.
5. Lines are marked according to given figure, using odd leg caliper and steelrule.

6. using the dot punch are made along the markedlines.

7. Theexcessmaterialsremovedfromtheremainingtwoedgeswithtrysquarelevelupto half of the

markeddots.
8. Finally buts are removed by the filling on the surface of the fittedjob.
RESULT
EX.NO: STUDYING THE WORKING PRINCIPLE OFAIR CONDITIONER

DATE:

AIM
The study of the window type air conditioner by dismantling and assembling the parts
sequentially.

TOOLS REQUIRED
Spanner set

PROCEDURE

1. Switch of the power supply and isolate the electrical connection from thesystem.
2. Remove the filter and grill from the system and place it on thework bench.
3. After checking and testing disconnect the circuit terminals from the operating
control systems such as thermostat, relay, capacitor, motor, selector switch and
compressor terminals.
4. Remove the evaporator and condenser cover and dismantle the condenser and
blower fan from the motor from the motor shaft by the help of Allenkey.
5. Remove the motor plates, clamps and clean the evaporator Condenser etc., with help
of brush and airblower.
6. Check the electrical parts and repair it ifnecessary.
7. Cleanthemotorandfixthefanandblowerassemblyproperlytothemotor.
8. Connecttheelectricalpartsasperthecircuitnotedbeforeandassemblealltheparts.
9. Clean the outer cover of the Air conditioner and place it on the properplace.
10. Fix the grill& filter, and test the functioning of the airconditioner.

RESULT
Thus the air conditioner is studied by dismantling and assembling the parts sequentially.
EX.NO: STUDYING THE WORKING PRINCIPLE OF CENTRIFUGAL PUMP
DATE:
AIM
To study the centrifugal pump by dismantling and assembling the parts sequentially.

TOOLS REQUIRED

1. Diespannerset 2.Box spannerset

3.Bearingpuller 4.Sledgehammer
5. Ball peen hammer 6.Tongs
PROCEDURE
1. Remove the motor from the base plate by removingthe pulley bolt and nut.
2. Remove the ump from base plate by unscrewing the base platenut.
3. Remove the pulley by striking it with the hammer & dismantlethe stuffing box flange.
4. Remove the outer cover of the vane by unscrewing the fasteners as well as the cotterpin.
5. Remove the vane mounted shaft by striking the shaft on the pulleyside.
6. Remove the vane from the shaft by unscrewing the brass locknut.
7. Remove the ball bearing from the bearingseat.
8. Clean all the removedparts.
9. Check the warned parts and replace it with newone.
10. Assemble the parts as per the above sequence in reversedirection.
Result

Thus the centrifugal pump is studied by dismantling and assembling the parts sequentially.
RESULT