study of jig machine, its types & operation present by Engr. umair raza

1. Study Of Jig
UMAIR RAZA / 19013386-002 (A)
BS- MECHANICAL ENGINEERING & TECHNOLOGY
Objective:
A jig is a device that can hold the workpiece & guiding a tool. A Jig is a type of Fixture with means for
positively guiding and supporting tools. The main purpose is to provide interchangeability, reduction of cost,
and accuracy of the manufactured Individual detail Parts, Sub - assemblies,
Sections, or main components, and finally the complete structure.
Jigs & Fixtures in Aircraft Industries
Factors should be considered before designing a jig :
 Study of the component.
 Study of locating elements.
 Type and capacity of the machine
 Loading and unloading arrangement.
 Clamping arrangement.
 Study of power devices for operating and clamping element and also a safety arrangement device.
 The clearance between a jig and the component.
 Study of tool guiding, cutter setting elements, rigidity and vibration problems.
 Fool-proofing arrangement.
 Study of ejecting devices, table fixing arrangement, and the indexing device.
 Swarf removal arrangement.
Types of jig:
 Template jig
 Jig & channel jig with work piece pots
 Angle plates jig
 Turn-over jig
 Leaf or Latch jig
 Box jig
 Trunnion-type indexing jig
 Sandwich & pimp jig
 Jigs for multi spindle machine
Origin: traced back to Swiss
watch and clock industry!

2. Study Of Jig
UMAIR RAZA / 19013386-002 (A)
BS- MECHANICAL ENGINEERING & TECHNOLOGY
Template jig:
A template jig is generally considered to be the
simplest type of jig. It is basically a plate with a
number of holes placed in a predetermined location
to aid in the quick manufacture of drilled parts. It
may also have a simple contour that is easily
followed with basic hand or power tools.
Channel jig
The channel jig is a simple type
of jig having channel like cross section. The
component is fitted within the channel is located
and clamped by locating the knob. The tool is
guided through the drill bush. 5: Leaf Jig: ... The
drill bushes are fitted into the plates, which is also
known as leaf , latch or lid.
Angle plates jig
An angle plate is a work holding device used as
a fixture in metalworking. The angle plate is made
from high quality material (generally
spheroidal cast iron) that has been stabilized to
prevent further movement or distortion. Slotted
holes or "T" bolt slots are machined into the
surfaces to enable the secure attachment or
clamping of workpieces to the plate, and also of the
plate to the worktable.
Turn-over jig
Workpiece having no suitable resting surface for
drilling can be drilled conveniently with turn-over
jig. Turn-over jig is plate jig with jig feet. Height of
the feet should no longer than the clamping stud.
Turn-over jig is turned over for loading and
unloading the workpiece. After loading the
workpiece, the jig must be turned over to rest on the
jig feet for drilling. Turn-over jis is also called table
jig.

3. Study Of Jig
UMAIR RAZA / 19013386-002 (A)
BS- MECHANICAL ENGINEERING & TECHNOLOGY
Leaf or Latch jig
Leaf or latch jigsare usedfor workpieceshaving
machinedsurface onthe side opposite tothe holes.Box
jigsare usedfordrillingholesfromanumberof sides
on lightworkpiece
Box jig
A jig in which work is rigidly held so that
it can be drilled or machined from different
angles at a single setting depending on
which face of the jig is turned toward the
tool.
Trunnion-type indexing jig
These jigs are used for drilling holes on very large
or odd. The parts is first put into a box type carrier
and then loaded on the trunnion.
The pin and the locating hole for the locking of the
jig should be wear resistant.
Multi station jig
Multi station jigs are made in any of the forms
already discussed. The main feature of this jig is
how it locates the work. While one part is drilled,
another can be reamed and third counter bored

4. Study Of Jig
UMAIR RAZA / 19013386-002 (A)
BS- MECHANICAL ENGINEERING & TECHNOLOGY
Jig design:
A jig's primary purpose is to provide repeatability, accuracy, and interchangeability in the manufacturing of
products. A jig is often confused with a fixture; a fixture holds
the work in a fixed location. A device that does both functions
(holding the work and guiding a tool) is called a jig. Suppose we
want to make a jug with a length of 50 mm and a diameter of 30
mm. We need to make a hole exactly 15 mm in diameter in the
middle of the bar. It is used for a special purpose. For example,
we use this jug when we have to make a 15 mm hole. When we
have to make a 15 mm hole in a small work piece, we should not
use it as it will only be a loss to our company. We can make holes in the work piece one by one in this case.
Application:
External Machining:
 Flat-Surface Machining
 Milling fixtures
 Surface-grinding fixtures
 Planning fixtures
 Shaping fixtures
 Cylindrical-Surface Machining
 Lathe fixture
 Cylindrical-grinding fixtures
Internal Machining:
 Cylindrical- and Irregular-Hole Machining
 Drill jigs
 Boring jigs
 Electrical-discharge-machining fixtures
 Punching fixtures
 Internal-broaching fixtures
Jigs Materials:
Materials used in Jigs and fixtures are made from a variety of materials, some of which can be hardened to
resist wear. Given below are the materials often used in jigs.Some common materials are as following.
 Hardened Steel.
 Carbide.
 Bronze.
 Stainless Steel
Conclusion:
Jigs is used to reduce the nonproductive time of any mass production process. Jigs save our money as well.
Jigs are essential elements of a manufacturing system. Responsible for holding the works accurately &
securely during its manufacturing, they determine to a large extent its relevant quality & their rate at which it
can be produced. Good design to jigs ensure that they fulfill their function economically is vital to the success
of the manufacturing system.

5. Study Of Jig
UMAIR RAZA / 19013386-002 (A)
BS- MECHANICAL ENGINEERING & TECHNOLOGY