Press tool manual
Published on: Mar 6, 2016
Transcripts - Press tool
Exercise No.: Date: / /
TITLE: Study and Design of Press Tool
After the completion of this exercise students will be able to know:
⇒ Desirable Properties of good cutting tools
⇒ Types of cutting tools
⇒ Basic geometry of single point cutting tool
⇒ Different angles associated with single point cutting tool
⇒ Importance of different angles of single point cutting tool in cutting process
The various press operations are as under:
(1) Blanking (2) Punching (3) Trimming (4) Shaving (5) Notching
(6) Perforating (7) Slitting (8) Lancing (9) Nibbling (10) Bending
(11) Drawing (12) Squeezing
Blanking: It is the process of producing a flat piece of material by cutting the
desired shape, in one operation. Here the article punched out is the ‘blank’ and is
the required product.
Punching: It is the operation by which various shaped holes are made in sheet
metal. It is similar to blanking except material punched out is scrap.
Trimming: Trimming is a process in which the outer perimeter of a formed or
flat part is cut away to give the piece part its finished or partially finished profile.
Shaving: It is the operation of removing the thin strips of metal from the
edges in order to make the product more accurate in dimensions.
Notching: Notching is a cutting operation that removes material from the edge
of the work piece.
Perforating:Perforating is a piercing operation that involves punching a large
number of closely spaced holes.
Slitting: It is the operation of making incomplete holes in work piece.
Lancing: Lancing is an operation in which the work piece is sheared and bent
with one strike of the die. A key part of this process is that there is not reduction
of material, only a modification in its geometry. This operation is used to make
tabs, vents, and louvers..
Nibbling:The nibbling process cuts a contour by producing a series of
overlapping slits or notches.
Bending: In this operation, the sheet metal is bent up to desired angle with use of
Drawing: It is process of forming a flat work piece into hollow shape by means
of punch which causes the blank to flow into a die cavity.
In this operation, the metal is caused to flow from die cavity by
application of compressive force in order to get the desired
shape.Classification of dies
According to type of operation.
1) Shearing – Blanking, piercing, punching, perforating, notching,
2) Bending – Forming, curling, angle bending.
3) Drawing – Cupping, forming flanges and tubes.
4) Squeezing – Coining, embossing and extruding.
According to specific construction
11 Single operation dies – (a) Cutting dies (b) Forming dies
11 Multi operation dies - (a) Compound dies (b) Combination dies
(c) Progressive dies
Simple Cutting Die & Assembly
Types of cutting dies
They perform single cutting operation such at one stroke of ram at the
same station these dies are called simple die. In this die, blanking operation
is performed during each stroke of the ram.
They perform two cutting operations such as blanking, piercing, notching
punching etc in each stroke of the ram at the same station. These dies are
called compound die. In this die, piercing and blanking operation is
performed during each stroke of the ram. For producing a washer with the
help of compound die, the first operation is blanking and then piercing
operation is performed with compound dies. We can produce washers or
link of chain of bicycle.
TWO OR MORE CUTTING, BENDING, FORMING OR CURLING OR
COMBINED OPERATIONS ARE PERFORMED IN EACH STROKE OF THE
RAM AT DIFFERENT STATIONS IN THESE DIES. WORK PIECE IN
PROGRESSIVE DIES TRAVELS FROM ONE STATION TO ANOTHER,
SEPARATE OPERATIONS BEING PERFORMED AT EACH STATION
USUALLY THE WORK PIECE IS RETAINED IN THE STOCK UNTIL IT
REACHES FINAL STATION. ALL STATIONS WORK SIMULTANEOUSLY BUT
AT DIFFERENT POINTS ALONG THE WORK STRIP. WORK STRIP
ADVANCES ONE STATION AT EACH STROKE OF RAM. STAMPING OF
TRANSFORMER OR ELECTRIC MOTOR, KEYS FROM SHEET METAL ARE
THE BEST EXAMPLES PRODUCED BY PROGRESSIVE DIES. FIGURE
ILLUSTRATES THE PROGRESSIVE DIE. PROPERTIES OF GOOD
1. Enlist the desirable properties of good cutting tool material.
2. Show with neat sketch the elements of Single Point Cutting tool.
3. Explain different cutting edge angles with neat sketch.
4. Explain the sign convention for back rake angle and end rake
5. Justify the suitability of positive and negative back rake angles.
6. Explain the various relief angles with neat sketch.
Discipline Understanding Total
4 2 4 10
Date: Signature of faculty member