Today we will discuss about what are Jigs and Fixture,
working, advantages and also difference between them. Before discussing about
it first you should learn the concept of Jigs and Fixtures. We know that
machining is the process of removing metal by the moving or stationary
work piece by use of tool. This process is done on some kind of machining like
lathe, milling, drilling etc. When the work piece is smaller and simpler it can
be easily mounted on the machine and we do not require any other mechanism to
hold the work piece (concept of Fixture) and guide the tool (concept of
Jigs). But in some cases when the work
piece is heavier and machining process is difficult some external mechanisms
are used to hold the work piece on machine and also guide the tool so accurate
machining can be done on work piece. These devices are known as jigs and
fixture.
Jigs and Fixtures are production tools used to accurately
manufacturing duplicate and interchangeable parts. They are specially designed
so that a large number of components can be machined or assembled identically,
and to ensure interchangeability of components. They eliminate the necessity of
a special set up for each individual part.
- Jigs and fixtures are precision tools.
- They are expensive to produce because they are made to fine limits from materials with good resistance to wear.
- They must be properly stored or isolated to prevent accident damage, and they must be numbered for identification for future use.
Jigs and Fixtures:
What is Jig?
A jig is a device in which a component is held and located
for a specific operation in such a way
that it will guide one or more cutting tools to the same zone of machining. The
usual machining operation for jigs are drilling and reaming. Jigs are usually
fitted with hardened steel bushings for guiding drills or cutting tools. The
most common jigs are drilling jigs, reaming jigs, assembly jigs etc. when these
are used they are usually not fastened to machine tools or table but are free
to be moved so as to permit the proper registering of the work and the tool.
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| Jig |
What is Fixture?
A fixture is a production tool that locates, holds and
supports the work securely in a fixed orientation with respect to the tool so
that the required machining operations can be performed. Fixtures vary in design
from relatively simple tools to expensive complicated devices. There are most
frequently attached to some machine tool or table. The most common fixture are
milling fixtures, broaching fixtures, assembly fixture etc.
 |
| Fixture |
Advantages of Jigs and Fixtures:
Jigs and fixtures are used in mass production of identical
parts. They gives following advantages.
- They improve productivity.
- It gives rapid production work.
- It reduced manufacturing costs.
- Complex and heavy components can be easily machined.
- Owing to high clamping rigidity, higher speed, feeds and depth of cut can be used.
- Jigs and fixtures are increased machining accuracy.
- It reduces in the expenditure due to inspection and quality control of finished components.
Difference between Jigs and Fixture:
S.No. |
Jigs |
Fixtures |
|
1.
|
Jigs incorporate bushes that guide the tools.
|
Fixture holds the component being machined with the cutters working
independently.
|
|
2.
|
Jigs are used on drilling, reaming, tapping and counter boring
operations.
|
They are used in connection with turning, milling, grinding, shaping,
planning, and boring operation.
|
|
3.
|
Jigs are depended on operation.
|
Fixtures are dependent on specific machine tools.
|
|
4.
|
They are lighter than fixture.
|
Fixture are heavier in construction and bolted rigidly on the machine table.
|
|
5.
|
They are more costly compare to fixture.
|
They are less costly.
|
|
6.
|
They are not fixed on machine table.
|
They are fixed on machine table.
|
This is all about Jigs and Fixtures uses, advantages and
difference between them. If you have any query regarding this article, ask by
commenting. If you like this article, don’t forget to share it on social
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