This document discusses flashless forging, a near net shape forging process where metal is compressed in a die cavity without any excess flash. Flashless forging provides benefits over closed die forging such as material and energy savings from eliminating flash, higher production rates due to no trimming, and better part dimensions and grain structure. While it enables net shape parts and savings, flashless forging also requires more complex dies and strict control over blank weight and temperature compared to conventional forging.

1. Seminar on
SEMINAR ON
FLASHLESS FORGING
By
Name-Anirudh kumar
Regd no- FF16M15 Sub- Near Net Shape Process
Branch-FFT
Batch-2016-18

2. INTRODUCTION
FORGING:-
Forging is a Bulk Deformation Process in which the
work is compressed between two dies to get a useful
required shape
According to the degree to which the flow of the
metal is constrained by the dies there are three types
of forging:
1. Open die forging
2. Impression die(closed die) forging
3. Flash-less forging

3. Types of forging
 Open die forging:-
work is compressed between two flat
dies, allowing metal to flow laterally
without constraint
 Closed die forging:-
Die contains a cavity or impression
that is imparted to workpiece, thus
constraining metal flow - flash is
created

4. Flashless forging
 It is true closed die forging in which metal deformed
in a die cavity permits virtually no excess metal to
escape
 During this process the preform is totally enclosed in
the die cavity so that no flash is formed
 In actual practice, a thin fin or ring of flash may form
in the clearance between the upper punch and die.
 This can be easily removed by blasting and doesn’t
require a trim die.

5.  This process carried out in an elevated temperature
which in between cold and hot forging.
 Work pieces are heated only to the level at which the
metal flows just enough, under forging pressure, to fill
the die but not so freely as to extrudes from closing die
halves before the cavities are filled.
This process is usually accomplished in one or two
process.

6. Preform design aspects
 Preform or blank weight:-To achieve complete filling of the
cavity without developing extreme pressures
 Metal volume should be controlled accurately.
 A small increase in volume will cause tremendous increase in
load, die stress, die wear.
 A decrease in volume, die will not fill completely.
Preform dimensions should be controlled accurately as it will
be enclosed completely in die.
 Preform and tooling temperatures:-
 To get high forge-ability the process can be carried out in an
isothermal forging operation where the die and punch
temperature is same as that of preform thereby it control the
thermal expansion and forging pressure

7. Process requirement
These are normally produced at a very high rate so
usually preferred where large production volume
required. To achieve this process requirements are:-
 The preforms, or blanks must be equal in weight
 Each preform must be heated to the same
temperature
 Proper positioning of billet inside the die

8. Benefits from flashless forging over
closed die forging
 Material waste:- in closed die forging operation, flash
averages 15-30% of original work piece. But Flashless
forging uses 100% of stock.
 Energy waste:- heating metal that will become flash,
transporting it, and then deforming it expends energy for
no useful purpose.
 Production time:- flash formation creates undesirable
internal structures in forging. Better control of grain flow
is achieved in flashless forging as it eliminates the grain
flow that lies at 90⁰ to the free surface as in close die
forging. Flash trimming operation and equipment used in
flash forging also again adds up cost and production time.

10. Advantages
 Material and energy saving
 No de-flashing operation
 Reduction of subsequent machining work through
smaller machining allowances and as a result of
lower tolerances of blank material
 Higher dimensional accuracy
 Higher production rate
 Higher strength and integrity as internal grain
structure follow flow of metal within the part
 Produced part are in net shape

11. Disadvantage
 Higher tooling cost due to complex die shape
 Requirement of high volume accuracy of blank
(deviation <5%) and thus in increased demand in
blank production
 The process requires a careful mass distribution

12. Flashless forging process need more careful die
design particularly for non-symmetrical part in
comparison to conventional impression die forging
process.
So the process lends itself best to part geometrics
that are usually simple and symmetrical .
Parts produced are:-
 Components for automative transmission
 Tracks in military vehicles
 Special piston for racing cars
 Aerospace components
 Connecting rod

13. THANK YOU