18-07-2016, 12:23 PM
Jigs and Fixtures:
Some machining operation are so simple’ which are done quite easily, such as turning, the job is held in position in the chuck and turning operation is done easily. No other device is required to hold the job or to guide the tool on the machine in such an operation. But some operations are such type in which the tool is required to be guided by means of another device and also some jobs are of such forms which are required to be held in position on the machine by means of another device.
The device which guides the tool is called jig and the device which holds the job in position is called fixture.
Jigs and fixtures are special purpose tool which are used to facilitate production (machining, asslembling and inspection operations), when work piece is based on the concept of interchangeability according to which every part will be produced within an established tolerance. Jigs and fixtures provide on means of manufacturing interchangeable parts since they establish a relation with predetermined to tolerance between the work and cutting tool. They eliminate the necessity of a special set up for each individual park. So’ A jig is may be de-fined as a device which hold and position the work; locate or guides the outing tool relative to the work piece and usually not fixed to the m/c table. It is usually lightly in construction.
A fixture is a work holding device and position the work; but doesn’t guide ‘locate or position the cutting tool’ the setting of the tool is done by machine adjustment and a setting blocker using slip gauges. A fixture is hold or clamp-ed to the machine table. It is usually heavy in construction. Jigs are used on drilling , reaming , tapping and couter boring operations , while fixtures are used in connection with turning , milling , grinding , shaping , planning and boring operations.
The use of jig and fixture makes possible more rapid and more accurate manufacturing at a reduction of cost.
Uses of Jigs and Fixtures:
Jigs and fixtures are used to reduce the cost of production as there use elimination being out work and setting up of tools.
To increase the production.
To assure the high accuracy of the parts.
To provide for interchangeability.
To enables heavy and complex shaped parts to be machined by holding rigidly to a machine.
To control quality control expenses.
Less skilled labor.
Saving labor.
There use partially automates the machine tool.
Improve the safety at work, thereby lowering the rate of accidents.
Jigs
The most-common jigs are drill and boring jigs. These tools are fundamentally the same. The difference lies in the size, type, and placement of the drill bushings. Boring jigs usually have larger bushings. These bushings may also have internal oil grooves to keep the boring bar lubricated. Often, boring jigs use more than one bushing to support the boring bar throughout the machining cycle.
reference;
http://www.mechengg2016/07/design-of-jig...lling.html
Some machining operation are so simple’ which are done quite easily, such as turning, the job is held in position in the chuck and turning operation is done easily. No other device is required to hold the job or to guide the tool on the machine in such an operation. But some operations are such type in which the tool is required to be guided by means of another device and also some jobs are of such forms which are required to be held in position on the machine by means of another device.
The device which guides the tool is called jig and the device which holds the job in position is called fixture.
Jigs and fixtures are special purpose tool which are used to facilitate production (machining, asslembling and inspection operations), when work piece is based on the concept of interchangeability according to which every part will be produced within an established tolerance. Jigs and fixtures provide on means of manufacturing interchangeable parts since they establish a relation with predetermined to tolerance between the work and cutting tool. They eliminate the necessity of a special set up for each individual park. So’ A jig is may be de-fined as a device which hold and position the work; locate or guides the outing tool relative to the work piece and usually not fixed to the m/c table. It is usually lightly in construction.
A fixture is a work holding device and position the work; but doesn’t guide ‘locate or position the cutting tool’ the setting of the tool is done by machine adjustment and a setting blocker using slip gauges. A fixture is hold or clamp-ed to the machine table. It is usually heavy in construction. Jigs are used on drilling , reaming , tapping and couter boring operations , while fixtures are used in connection with turning , milling , grinding , shaping , planning and boring operations.
The use of jig and fixture makes possible more rapid and more accurate manufacturing at a reduction of cost.
Uses of Jigs and Fixtures:
Jigs and fixtures are used to reduce the cost of production as there use elimination being out work and setting up of tools.
To increase the production.
To assure the high accuracy of the parts.
To provide for interchangeability.
To enables heavy and complex shaped parts to be machined by holding rigidly to a machine.
To control quality control expenses.
Less skilled labor.
Saving labor.
There use partially automates the machine tool.
Improve the safety at work, thereby lowering the rate of accidents.
Jigs
The most-common jigs are drill and boring jigs. These tools are fundamentally the same. The difference lies in the size, type, and placement of the drill bushings. Boring jigs usually have larger bushings. These bushings may also have internal oil grooves to keep the boring bar lubricated. Often, boring jigs use more than one bushing to support the boring bar throughout the machining cycle.
reference;
http://www.mechengg2016/07/design-of-jig...lling.html