LATHE IN WORKSHOP TECHNOLOGY

Lathe is a machine tool which rotates about its own axis and to perform various operations such as cutting, knurling, drilling, turning. Lathe plays an important role in industrial revolution, and it is called as mother of machine. 

HISTORY

The first lathe was used in the 1300 BC in EGYPT. There is also evidence that these lathes are used in Greek during 14th century BC. In the early 400 BC China also used lathes to manufacture some small bowls and to design some weapons as well. During 6th century BC fragments of wooden bowl have been found in northern ITALY and TURKEY. During 400 BC the ancient Chinese people used rotary lathe tools to sharpen tools. 

     

Main parts of lathe 

1. Head stock

2. Tail stock

3. Carriage 

4. Cross slide

5. Saddle

6. Tool post

7. Feed box

8. Compound rest

                                         

1.Head stock:

Headstocks are the main body parts that are placed on the left side of the bed.

It serves as a holding device for gear chains, spindles, driving pulleys, etc.

2.Tail stock:

Tailstock is a casting located on the right side of the bed.

Its function is to support the loose end of the workpiece or a job while machining.

It can slide on the bed guideways and can be clamped in any position.

The tailstock has the following purposes:

1. To support the loose ends of long jobs for carrying out lathe operations.

2. To hold the cutting tools such as drill chucks, drills, reamers, etc.

3. Turning of outer taper by an offsetting method.

3.Carriage:

It is located between headstock and tailstock.

It is used to hold and move the tool post along the bed either towards or away from the

It slides on the guideways.

It is also made of cast iron.

4.Cross slide

A cross slide is a part of the carriage that allows the movement of a tool post at a right

angle to the bed guideways during machining.

The cross slide is moved by the feed screw.

5.Saddle:

It is an 'HI shaped casting mounted on lathe ways, supports the cross slide that provides movement to the tool post.

6.Tool post:

It is bolted to the carriage on top of the compound slide.

It is used to hold the tools at the correct position with rigidity.

7.Feed box:

It consists of interchangeable gear drives in a housing The kinematic features of the feed

box make possible exact matching of the movement of the tool feed during the shaping of the

workpiece (cutting threads and teeth) with other movements of the tool relative to the

workpiece.

8.Compound rest:

A compound rest is a part that connects the cross slide and the compound slide.

The compound rest is mounted on top of the cross slide.It has a circular base on which the graduations in degrees are made.

Its power is not fed but it is operated by hand.

A certain depth of cut can be set by rotating the feed screw of the compound rest.

After setting it as required, the compound slide is solidly locked with the base.