PPT on Manufacturing Engineering-III (PPT on Lathe Machine)

1. SIGMA POLYTECHNIC
Saini Tarandeep Singh (126420319613)
Department : Mechanical Engineering (19)
Sem : 5th Sem
Year : 2015-2016
Subject : Manufacturing Engineering – III
(3351903)

2. LATHE
MACHINE

3. LATHE MACHINE :

4. Figure shows the working principle of
lathe machine. The work-piece is either
held in chuck or between two centers
and rotated. Suitable cutting tool is held
in tool post and by selecting suitable
cutting parameters and with relative
working motions between work-piece
and cutting tool. Unwanted material is
removed from the work-piece in the
form of chips to get desire shape, size
and finish.
WORKING PRINCIPLE OF LATHE MACHINE :

5. Working Principle of Lathe Machine

6. 1.Speed Lathe
2.Engine Lathe
3.Bench Lathe
4.Tool Room Lathe
5.Capstan and Turret Lathe
6.Special Purpose Lathe
7.Automatic (CNC) Lathe
CLASSIFICATION OF LATHES :

7. 1. Speed Lathe :
It is the simplest of all the lathes. It consists of a bed, a headstock
tailstock and an adjustable slide for supporting the tool post. It is
driven by a variable speed motor built on the headstock.
2. Engine Lathe :
This lathe is one of the most important members of lathe family. In
old days this lathe was driven by steam engine. Hence it is known as
engine lathe. It is also known as Centre lathe.
3. Bench Lathe :
This is a vary small lathe mounted on the work bench. The parts of a
bench lathe are similar to that of the engine lathe but the only
difference of size. Bench lathe are used for small jobs.
4. Tool Room Lathe :
It is used to make small tools in the shop floor. This is much
accurately built than the engine lathe with large range for spindle
speeds up to 2500 rpm.

8. 5. Capstan and Turret Lathe :
They are developed version of engine lathe. They are
popularly used for production work. In this type of
lathes no tailstock is used, but a hexagonal turret
replaces the tailstock.
6. Special Purpose Lathe :
This type of lathes are used for definite type of work
and also for the jobs which are difficult to manufacture
on standard lathe.
7. Automatic Lathe :
This lathe is provided with automatic control and it is
high speed and heavy duty mass production lathe.
Here once the tool is set the entire product gets ready
automatically. Changing of tools, speed, feed, etc. are
performed automatically.

9. The major components are :
1. Bed
2. Head Stock
3. Tail Stock
4. Carriage
5. Feed Mechanism, etc.
6. Screw Cutting Mechanism.
CONSTRUCTION OF LATHE MACHINE :

10. Block Diagram of a Lathe Machine

11. 1. bed :
Lathe bed is made from cast-iron which gives more
strength required. Nickel cast-iron alloy is used. It
provides support to headstock, tailstock and carriage.
2. Head stock :
A permanently fitted unit on the inner side of the lathe bed
and on left hand side is called headstock. Its function is to
furnish power to work-piece and tool to provide different
speed for work-piece mechanism is provided in the
headstock.
3. Tailstock :
The assembly mounted on the right hand side of bed on
inner ways of lathe bed is known as tailstock.

12. Tailstock is used for many functions such as :
i. To support long work-piece.
ii. To facilitate drilling, tapping, reaming
operation.
iii. For taper turning by off setting the tails for
long work-piece. Tail stock comprises of
body, sleeve, screw, bush, hand wheel, etc.
Figure shows one such tailstock and its
components.

13. Tail Stock

14. 4. Carriage :
Carriage of a lathe contains following :
a. Saddle c. Cross Slide
b. Apron d. Compound Rest
The function of the carriage is to support the cutting tool,
to give feed to the cutting tool and to control the cutting
action. The function of the saddle is while sliding on their
lathe ways is supports cross slide, compound rest and
tool post. Apron comprises of driving mechanism and
facilitates manual as well as power feed to the carriage.
Cross slide is used to provide cross feed to the tool that
is feed motion at right angle to the axes of the lathe.
Compound rest is used to provide angular feed for tapper
turning to the tool.

15. 1.Straight Turning
2.Tapper Turning
3.Facing
4.Chamfering
5.Thread Cutting
6.Knurling
7.Grooving
OPERATIONS WHICH ARE PERFORMED BY HOLDING THE WORK-PIECE
BETWEEN CENTRE'S OR IN CHUCK. SUCH AS :

16. 8.Filing
9.Spinning
10.Forming
11.Polishing
12.Eccentric Turning
13.Shoulder Turning
14.Spring Winding