Everything about the process of turning you'll find in this beautiful report

1. UNIVERSITY OF TECHNOLOGY
DEPT. OF PRODUCTION
ENGINEERING & METALLURGY
PRESENTATION OF
LATHE MACHINE

2. INTRODUCTION
 A lathe is probably the oldest machine tool, stemming from the early tree lathe, which was
turned
by a rope passed around the work a few times and attached to a sparingly branch overhead.
The
work was supported by two dowels struck in adjacent trees. The operator’s foot supplied the
motion,
 which was intermittent and fluctuating. The tool was held in the operator’s hand. Later a strip of
wood called a “lath” was used to support the rope and hence named as Lathe. From this crude
beginning and over period of more than two centuries, the modern engine lathe has evolved.
Until
about 1770, lathes were useless for metal cutting because they lacked power and a holding
device
strong enough and accurate enough to guide the tool. For its development to the form in which
we
know it now, we owe much to Henry Mauldsley, who developed the sliding carriage and in
1800 built
 a screw cutting lathe. Nowadays, it has become a general purpose machine tool, employed in
production and repair work, because it permits a large variety of operations to be performed
on it.

3. LATHE MACHINE

4. BASIC WORKING PRINCIPLE OF
LATHE MACHINE
 Lathe removes undesired material from a rotating work piece in the form of chips with the help of
a tool which is traversed across the work and can be fed deep in work. The tool material should
be harder than the work piece and the latter held securely and rigidly on the machine. The tool
may be given linear motion in any direction. A lathe is used principally to produce cylindrical surfaces
and plane surface, at right angles to the axis of rotation. It can also produce tapers and bellows
etc. Operation of turning is done on parts as small as those used by watches to huge parts weighing
several tons.
 A lathe basically consists of a bed to provide support, a headstock, a cross slide to traverse the
tool, a tool post mounted on the cross slide. The spindle is driven by a motor through a gear box to
obtain a range of speeds. The carriage moves over the bed guide ways parallel to the work piece
and the cross slide provides the transverse motion. A feed shaft and lead screw are also provided
to power the carriage and for cutting the threads respectively.

5. 5
We often hear about Islam, what is Islam ?
Learn through these sites about Islam and to all questions that revolve in your
thoughts about this religion, and raise the level of your culture in learning
religions enjoy the following sites to know everything about Islam :-
My first step in Islam :-
( http://www.1ststepsinislam.com/en/introduction.aspx )
Women in Islam :-
( http://womeninislam.ws/en/introduction.aspx )
The key to understanding Islam :-
http://www.thekeytoislam.com/
This is true :-
http://www.thisistruth.org/
Learn about Islam will change your life , There is no money nor power nor any
thing can change your life ,Islam will change your life and you will feel very happy.
We often hear about Islam, what is Islam ?
Do you have money and everything but feel dissatisfaction in your heart is not the
goal of your life?! Do you want to save you from this case?
Introduction to Islam through these sites and I promise you will find great pleasure
My first step in Islam :-
( http://www.1ststepsinislam.com/en/introduction.aspx )
Women in Islam :-
( http://womeninislam.ws/en/introduction.aspx )
The key to understanding Islam :-
http://www.thekeytoislam.com/
This is true :-
http://www.thisistruth.org/
My brother, my sister, after that follow the religion of truth and become a Muslim This
site should catch a lot (the new Muslim guide)
http://www.newmuslimguide.com/en/store
Learn about Islam will change your life , There is no money nor power nor any
thing can change your life ,Islam will change your life and you will feel very happy.

6. OPERATIONS PERFORMED ON LATHE
MACHINE
 The most common operations which can be performed on the
lathe are
1. Facing, 2. Turning,
3.Taper turning, 4. Eccentric turning,
5. Boring, drilling, 6. Reaming,
7. Threading, 8. Knurling, and
9. Scroll cutting etc.
 In addition to it, with the help of special attachments,
operations like
1. Keyway cutting, 2. Cam and gear cutting,
3. Shaping, 4. Milling,
5. Fluting, and
6. Grinding can also be performed on this machine

7. THESE OPERATIONS ARE DISCUSSED AS
FOLLOWS:
 Facing
 This operation is almost essential for all works. In this
operation, as shown in Fig.2, the work piece is held in
the chuck and the facing tool is fed from the centre of
the work piece towards the outer surface or from the
outer surface to the centre, with the help of a cross-
slide.

8. PLAIN TURNING
 It is an operation of removing
excess amount of material from
the surface of the cylindrical work
piece. In this operation, as shown
in Fig. 3 the work is held either in
the chuck or between centres and
the longitudinal feed is given to
the tool either by hand or power.

9. STEP TURNING
 It is an operation of producing
various steps of different
diameters in the workpiece, as
shown in Fig.4 This operation is
carried out in the similar way as
plain turning.

10. TAPER TURNING
 It is an operation of producing an external conical surface on a work
piece. A small taper may be produced with the help of a forming tool or
chamfering tool, but the larger tapers are produced by swiveling the
compound rest, as shown in Fig. 5 at the required angle or by offsetting
the tailstock or by taper turning attachment.
 Note. If D is the larger diameter, d is the smaller diameter and L is the
length of taper, as shown in Fig. 5, then

11. DRILLING
 It is an operation of making a
hole in a work piece with the help
of a drill. In this operation, as
shown in Fig. 6, the work piece is
held in a chuck and the drill is
held in the tailstock. The drill is
fed manually, in to the rotating
work piece, by rotating the
tailstock hand wheel.

12. REAMING
 It is an operation of finishing the
previously drilled hole. In this
operation, as shown in Fig. 7, a
reamer is held in the tailstock
and it is fed into the hole in the
similar way as for drilling.

13. BORING
 It is an operation of enlarging of a
hole already made in a work
piece. In this operation, as shown
in Fig. 8, a boring tool or a bit
mounted on a rigid bar is held in
the tool post and fed into the work
by hand or power in the similar
way as for turning.

14. UNDERCUTTING OR GROOVING
 It is an operation of reducing
the diameter of a work piece
over a very narrow surface. In
this operation, as shown in
Fig. 9 a tool of appropriate
shape is fed into the revolving
work up to the desired depth
at right angles to the centre
line of the work piece.

15. THREADING
 It is an operation of cutting helical
grooves on the external cylindrical
surface of work piece. In this
operation, as shown in Fig .10 the
work is held in a chuck or between
centres and the threading tool is
fed longitudinally to the revolving
work. The longitudinal feed is
equal to the pitch of the thread to
be cut.

16. 16
We often hear about Islam, what is Islam ?
Learn through these sites about Islam and to all questions that revolve in your
thoughts about this religion, and raise the level of your culture in learning
religions enjoy the following sites to know everything about Islam :-
My first step in Islam :-
( http://www.1ststepsinislam.com/en/introduction.aspx )
Women in Islam :-
( http://womeninislam.ws/en/introduction.aspx )
The key to understanding Islam :-
http://www.thekeytoislam.com/
This is true :-
http://www.thisistruth.org/
Learn about Islam will change your life , There is no money nor power nor any
thing can change your life ,Islam will change your life and you will feel very happy.
We often hear about Islam, what is Islam ?
Do you have money and everything but feel dissatisfaction in your heart is not the
goal of your life?! Do you want to save you from this case?
Introduction to Islam through these sites and I promise you will find great pleasure
My first step in Islam :-
( http://www.1ststepsinislam.com/en/introduction.aspx )
Women in Islam :-
( http://womeninislam.ws/en/introduction.aspx )
The key to understanding Islam :-
http://www.thekeytoislam.com/
This is true :-
http://www.thisistruth.org/
My brother, my sister, after that follow the religion of truth and become a Muslim This
site should catch a lot (the new Muslim guide)
http://www.newmuslimguide.com/en/store
Learn about Islam will change your life , There is no money nor power nor any
thing can change your life ,Islam will change your life and you will feel very happy.

17. KNURLING
 It is an operation of providing
knurled surface on the work piece.
In this operation, as shown in Fig.
11, a knurled tool is moved
longitudinally to a revolving work
piece surface. The projections on
the knurled tool reproduce
depressions on the work surface.

18. TERMS USED IN LATHE MACHINING
 The following terms are commonly used while machining a
work piece on lathe.
1. Cutting speed:
It is defined as the speed at which the metal is removed by
the tool from the work piece. In other words, it is the peripheral
speed of the work past the cutting tool. It is usually expressed
in meters per minute.
2. Feed:
It is defined as the distance which the tool advances for
each revolution of the work. It is usually expressed in
millimeters.
3. Depth of cut:
It is defined as the depth of penetration of the tool into the
work piece during machining. In other words, it is the
perpendicular distance measured from the machined surface
to the unmachined surface of the work piece. It is usually
expressed in millimeters.