It's a project focused on reducing the scraps and increasing the efficiency and Quality of the Castings..

1. COST REDUCTION IN MELTING- A
SQC & SIX SIGMA APPROACH
ARUN KUMAR.S,
B.E.MECHANICAL ENGINEERING
FINAL YEAR
RAJA COLLEGE OF ENGG.&TECH.

2. FOUNDRY
• A Foundry is a factory that produces metal, castings.
• Metals are cast into shapes by melting them into a
liquid, pouring the metal in a mould, and removing the
mould material or casting after the metal has solidified
as it cools.
• The most common metals processed are
aluminium and cast iron.
• However, other metals, such
as bronze, brass, steel, magnesium, and zinc, are also
used to produce castings in foundries. In this process,
parts of desired shapes and sizes can be formed.

3. FOUNDRY-PROCESSES
PATTERN MAKING
METHODING
MOULDING
MELTING
LAB TESTS
FETTLING
QUALITY CONTROL
DESPATCH

4. ARUNAALLOY STEELS(AAS)-
COMPANY PROFILE
 The temple city of Madurai houses a world class foundry
“ARUNA ALLOY STEELS PVT LTD.”, a versatile
company which laid down its roots in the memorable
year of 1961 as a small scale industry.
 Down the years of its growth, the company became the
suppliers to our country’s prestigious Indian Railways
for more than 3 glorious decades.
 When the Vacuum brake system in the Railways
became obsolete, the company also changed tracks in
Manufacturing to Automotive castings, Flywheel, brake
drum, and Gear & Clutch Housings.

5. ARUNAALLOY STEELS(AAS)-
COMPANY PROFILE
 From 1998 ARUNA is forging ahead to dedicate itself
exclusively to VALVE industry.
 ARUNA has excelled itself in the faultless supply of
high performance of widely varied valves for
maximum pressure rating up to “5000 PSI and size 30
Inch.”
 ARUNA is manned by Mr.SV. Arunachalam who is a
proud recipient of the “All India Best Foundry Man of
the Year 2003-2004 award.”
 The company is now a World-class certified supplier of
steel castings to reputed valve manufacturers both in
the domestic and international arena.

6. MELTING
Melting is a physical process that results in
the phase transition of a substance from a solid to
a liquid.
 The internal energy of a substance is increased,
typically by the application of heat or pressure,
resulting in a rise of its temperature to the melting
point, at which the ordering of ionic or molecular
entities in the solid breaks down to a less ordered
state and the solid liquefies.
 An object that has melted completely is molten.

7. MELTING
Melting Techniques:
There are a variety of methods used in foundries
for melting the metal for casting.
 The selection of an appropriate technique is
dependant on factors such as the metal being
melted, the amount of molten metal required for
the production run and the area available to house
the melting equipment.
The range of melting equipment typically used
can be categorised as follows:

8. MELTING
Electric Arc Furnaces
Induction Furnaces
Vacuum Induction melting
Hearth Furnaces
Crucible Furnaces
Cupola Furnaces
Vacuum Arc Skull Melting and Casting

9. INDUCTION FURNACES
 A water cooled copper coil carrying alternating current
produces a magnetic field, which in turn induces eddy
currents in the charge.
 These eddy currents heat and eventually melt the
metal.
 A second magnetic field is generated by the induced
current in the charge.
 The opposed magnetic fields result in a mechanical
force, which stirs the molten metal.
 The benefits of this stirring include the production of a
thermally and chemically homogeneous melt and
excellent alloy and charge absorption.

10. POURING
 In a foundry, molten metal is poured into moulds.
 Pouring can be accomplished with gravity, or it
may be assisted with a vacuum or pressurized gas.
 Many modern foundries use robots or automatic
pouring machines for pouring molten metal.
Traditionally, moulds were poured by hand
using ladles.

11. LAB TESTS
The following are some of the tests being carried out in chemical lab:
 Micro structure of Scraps;
 Compression strength; Permeability and Moisture content of Mould
& Core Sand.
 Chemical composition of Castings(Bath1&2 and final).
The following are some of the tests being carried out in mechanical lab:
 Hardness;
 Yield Strength;
 Ultimate Tensile Strength;
 Elongation%;
 Reduction%.

12. FETTLING
• The foundry Cleaning Room is collection
processes where castings are ‘finished’ to meet
the customers specifications.
• Once poured, the moulds are allowed to cool
before next being sent to the shakeout.
• At the shakeout, the castings are separated
from the sand mould.
• The sand is sent to a reclamation system so
that it can be reused in the moulding process.

13. FETTLING
• For some metal types, and with some gating system designs,
the sprue, runners and gates can be removed by breaking
them away from the casting with a sledge hammer or
specially designed knockout machinery.
• The gating system required to produce castings in a mould
yields leftover metal, including heads, risers and sprue,
sometimes collectively called sprue, that can exceed 50% of
the metal required to pour a full mould.
• Since this metal must be remelted as salvage, the yield of a
particular gating configuration becomes an important
economic consideration when designing various gating
schemes, to minimize the cost of excess sprue, and thus
melting costs.

14. FETTLING
• Heat treating is a group of industrial and
metalworking processes used to alter the physical,
and sometimes chemical, properties of a material.
• Heat treatment involves the use of heating or
chilling, normally to extreme temperatures, to
achieve a desired result such as hardening or
softening of a material.
• Heat treatment techniques include annealing, case
hardening, precipitation strengthening, tempering
and quenching.

15. PROBLEM DEFINITION
• Usage of more scraps leads to more cost.
• This can be controlled by using SQC(Statistical
Quality Control) and Six Sigma.
• Some of tools that can be used are:
 Pareto charts
 Fish-Bone Diagram
Hypothesis testing
 Control charts…

16. EXPERIMENTAL DATA
Taken melts of WCB without returns.
Taken melts of WCB with returns.
Taken melts of CK3MCuN without
returns.
Taken melts of CK3MCuN with returns.

17. CK3MCuN GRADE WITH& WITHOUT
RETURNS
Heat No SCRAP Status RT NSD % WELD Chem Mech
K7748 406.75 Rejection 50 Ok Ok
K7837 416.35 Rejection 50 Ok Ok
K7668 413.41 Rejection 75 Ok Ok
K7715 406.23 ok 100 1.87% Ok Ok
K7502 413.71 ok 100 0.82% Ok Ok
K7378 409.1 Rejection Ok Ok
K7432 413.59 ok 100 0.89% Ok Ok

18. CK3MCuN GRADE WITH& WITHOUT
RETURNS
Heat No SCRAP+RET Status RT NSD % WELD Chem Mech
K7868 390.44 ok 100 Ok Ok
K7906 391.27 ok 100 Ok Ok
K7629 364.62 Rejection 50 Ok Ok
K7643 392.54 Rejection 50 Ok Ok
K7513 408.99 Rejection 50 Ok Ok
K7521 401.01 R ok 100 0.93% Ok Ok

19. WCB GRADE WITHOUT RETURNS
HEAT NO: NSD% WELD%
K6739 78.90% 3.22%
K6740 81.50% 1.78%
K6741 82.90% 5.11%

20. WCB GRADE WITH RETURNS
HEAT NO: NSD% WELD%
K6748 63% 15.17%
K6751 81.50% 1.66%
K6752 75.30% 9.66%
K6756 89.50% 0.52%
K6761 63.20% 3.67%
K6762 73.70% 3.18%
K6764 48.60% 3.54%
K6765 94.60% 0.78%
K6766 83.80% 1.81%

21. WCB GRADE WITHOUT RETURNS
90.00%
80.00%
70.00%
60.00%
50.00%
40.00%
30.00%
20.00%
10.00%
0.00%
K6739 K6740 K6741
NSD% WELD%

22. WCB GRADE WITH RETURNS
100%
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
NSD% WELD%