USAGE OF CARBON
DIOXIDE IN FOUNDRY INDUSTRY
Process of making a metal casting of an
By pouring molten metal into a mould.
Mould is made using a pattern of the article
Two Types of Foundries
1. Ferrous foundry \96 to produce
Iron & Steel Castings
2. Non-Ferrous \96 to produce Copper based
alloys (brass, bronze & copper)
to produce Aluminium Based Alloys (lead,
zinc, nickle, magnesium)
to produce other Alloys
Foundry Process Map
1. Sand Mixing
Once sand (refractory), clay (bentonite)
and water are mixed to a desired consistancy,
the sand must be mulled. Spread sand on
a clean hard floor to a depth of about 6".
Stomp down hard on the sand until it is
all packed tight.
2. Pattern & Moulding
Section Keep the required pattern
\96 items to be moulded \96 inside the box.
The mixed sand (core material \96 silica sand
and sand binders) is filled in the frame
over the patterns. The filled-in sand is
ramming hardly on the pattern. This is called
core. Cores are moulded sand shapes placed
inside moulds to define a cavity inside
the final casting. In general, cores must
be strong to withstand molten metal and
at the same time, should become loose to
breakdown into sand after pouring &
3. Moulding Process
\96 Adding Co2 Moulding is a process of mixing
sand and binders to give the necessary strength
to the core. Sand binders are liquid resins
/ catalysts and its selection is based on
their curing (hardening) time of the sand
mixture. \93Cold-box\94 systems require gassing
or curing at room temperature. Core is cured
using a vaporised (gas) catalyst \96 the most
preferred one is Carbon Dioxide (Co2)
\95 In short, Co2 is referred
to as silicate binder in core making
Development of Co2 mould laid the foundation
for future success of foundry industry.
Co2 sodium silicate facing sand with green
sand backing became the standard technique
employed on all moulds.
4. Pouring &
Liquid metal is poured into the core
any information / Co2 requirements, contact
VI Floor, Dhun Building, # 84, (Old No.
827), Anna Salai, Chennai-600 002.
Phone : 91 - 044 - 2852
1644 / 2852 1467 / 2852 0657 / 2852 0870
Fax : 91 - 044 - 2852 1249,
Phono No: 044 39850715/728
At : Bangalore, Chennai, Cochin, Coimbatore,
Goa, Hyderabad, Indore, Kakinada, Kolkata,
Madurai, Mumbai, Surat, Tuticorin, Vadodara,