1.INTRODUCTION
1.1 NECESSITY OF PROFESSIVE DIE IN MASS PRODUCTION
In today’s industrial era the main basic thing for any industry is to produce
and manufacture the product with shortest Lead time and with greatest
accuracy. Also grate care is taken to maintain international quality
and to over come these problems we can o for progressive
dies.Progressive die is widely used in our present day manufacture
industry. These dies play a vital role in each and every operation that
lead to manufacturing of certain components. Further the dies are
classified according to the type of operation performed by them.
SOME OF THE IMAGES OF PROGRESSIVE TOOL ARE
(A)Piercing:
The piercing is the operation of production of hole in a sheet metal by
the punch and the die. The material punched out to form the hole
constitutes the waste. The punch point diameter In the case of piercing
in less than or equal to the work material thickness. The punch governs
the size of the hole and the clearance is allowed on the die.
(I) bending :
The punching operation is similar to the piercing operation. While
punching the formation of the hole is the desired result. The
difference between the punching and the piercing is that in the case of
punching a cylindrical hole is produce, where as in the case of
piercing the hole produced may be of any other shape. The size of the
hole is determined by the size of the punch and the clearance is
allowed on the die.
©Perforating:
The perforating is the operation of production
of a number of holes evenly spaced in a regular pattern on a sheet
metal.
(D)Blanking:
The blanking is a operation of cutting of flat
sheet of the desired shape the metal punched out is the required
product and the plate with the role left on the die goes as waste.
While blanking
(d) Cutting off:
The size of the blank of the die and the clearance is left on the punch.
The cutting off is the operation of shearing a piece from a sheet of
metal or a bar with a cut along a single line. The cutting off
operation can be performed along a straight line or a curve.
(E)Parting:
The parting is the operation of cutting a sheet metal in two parts.
Unlike cutting off operation, some quality of scraps is removed to
shear the work piece in two parts.
(f)Notching:
The notching is the operation of removal of the desired shape from the
edge of a plate. This operation removes a small amount of material from
the edges of a strip or a blank. Nothing serves to shape the outer
contours of the work piece in a progressive die or to remove excess
metal before a drawing or forming operation in a progressive die.
(g)Embossing:
The embossing die is used to press letters and number onto a sheet
metal or on predawn piece part. The forms of the script are engraved
and polished usually the punch bears the raised from and die bears the
cavity.
(h)Coining:
Coining is the process of pressing cold material in a die so that it
flows into the engraved profiles on the die face. Coining differs from
embossing such that in coining the metal flows, where as in embossing
the metal thus not changes in thickness to great extent.
round straight axis which extends completely across the material. The
result is a plane surface at an angle to the original plane of the flat
blanked component. Metal flow is uniform along the bend axis.
(j)Forming:
The operation of forming is similar to bending aspect that the line of
bend is along a curved axis instead of a straight. Metal flow is not
uniform as in bending because it may be localized to some extent
depending up on the shape of the work piece.
(K) Drawing:
In drawing a flat blank is transformed in to a cup or shell, the parent
metal subjected to several plastic deformation. Shell forms produced
may be cylindrical or rectangular with straight tapered sides.
NEED FOR DESINGNING OF PROGRESSIVE DIE
Die design, a large division of tool engineering is a complex,
fascinating subject. It is one of the most exciting of all areas of the
general field of tool designing. The die designer originates designs of
the die employed to stamp & form parts from sheet metal, assemble
parts together & perform variety of other operations,
Today `s industrial era demands something that is simple and economical
.in this regard the progressive die will play a very important role. A
progressive die is a die which can perform a number of operations at
each press of ram. And hence will be the brightest future in the mass
production area. Let`s see some of the advantages and disadvantages.
1.2ADVANTAGES AND DISADVANTAGES OF PROGRESSIVE DIE.
Advantages:
• If the pierced holes are too near to the outer edge of the piece
part, the blanking punch of a compound die which accommodates the
piercing dies will be come very weak.
• The posses a very big disadvantage of punch breakage either during
manufacturing or during the course of the die life. For such piece
parts the best solution is always a progressive die.
• Compound dies generally uses more than one press along with secondary
press. Where as progressive die needs only one press even for to work
stations.
• Progressive dies increases the annual production to a high volume(thus high scale production only through progressive die)
Disadvantages:
• Parts produced from compound die are very accurate and identical as
all operations are carried out in a single station. this is made
possible because the accuracy the part does not
• Depend on the accuracy of the advance of the strip or the accuracy of the layout of the stations as in the progressive die.
• Scrape stocks from other dies can be economically employed to produce
piece part in a compound die whereas progressive die always need stock
strip sheared to size.
• In a compound die burrs resulting from piercing and blanking are on
the same side of the piece part. Piece parts produced by a progressive
die have the burrs on the opposite sides.
• Die cost incurred in manufacturing a compound die is lesser then that
of a progressive die made for the same component because of its smaller
size and easier manufacturing methods warranted.
Thus we need to design a progressive die for better scale of production and effective use.
1.3METHOD OF DESIGNING A PROGRESSIVE DIE
• The first step of designing a progressive die is to study the piece
pat drawing carefully and to plan the operations to be carried out in
different stations.
• The drawing of the stock strip is laid out as it will appear after it
as gone through all stations, till a finished piece part is removed
from it.
• It should be dimensioned and should carry all information’s necessary
to start with the tool design like the feed direction, the amount by
which the strip advances after each stroke of the press.
• The blank must be positioned in the strip so that a maximum area of the strip is utilized for the production of the stepping.
• The existence of numerous die stations having many punches tends to
weaken the over all die. Than one or more idle stations, where now
operations or performed should be included. The addition of an idle
station is also called for when the punches from two active stations
are too close to each other.
• Although idle stations are often included to strengthen a die, at
times they are also included in order to case of die maintenance to
provide flexibility in the event that additional need to be added later.
• Most stamping operations are carried out on parts less than 200mm is
size using progressive die. Large parts are not usually produced on
progressive dies because the size of die becomes exorbitantly large.
• Progressive dies can produce a complete part without any secondary
operations. Then are capable of high speeds & high degree of
accuracy they can be engineered to produce very complex parts.
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