1. The document describes the process of preparing and managing green sand in a cast iron foundry. It involves mixing sand, clay, water, and other additives to form green sand that is then used to create molds in molding machines. 2. The green sand is then used in the molding process where molds are produced and molten metal is poured. After solidification, the molds are shaken to separate the casting from the sand for reclamation. 3. The returned sand is processed to remove impurities before being dried and mixed with new sand in preparation for reuse in the molding process. Proper management of foundry sand includes reclamation, recycling, and disposal to reduce waste.

1. PreparationOFSANDFLOWSYSTEM INA
CAST IRONFOUNDRY

2. Cast Iron 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 mold.
• Cupola furnace is a melting device used in foundries to melt cast
iron.

3. Green Sand Description
• The word ‘Green’ signifies that the moulding sand is in moist state at the time of
metal pouring.
• Green sand is not green in color, but "green" in the sense that it is used in a wet
state.
• Unlike the name suggests, "green sand" is not a type of sand on its own, but is
rather a mixture of:
 Silica sand (SiO2), or Chromite sand (FeCr2O), or zircon sand (ZrSiO4), 75 to 85%, or
olivine, or Staurolite, or graphite.
 Bentonite (clay), 5 to 11%
 water, 2 to 4%
 inert sludge 3 to 5%
 Anthracite (0 to 1%)

4. Preparation of green sand
High Intensity Green Sand Mixers
•Complete Integrated Green Sand Plants
•Rotary Knockout and Cleaning Drums
•Rapid Homogenous Mixing
•Low Operating and Maintenance Costs
•Automatic Moisture Control and Batch Weighing
•High Quality Sand
•Automated Sand Plants
•Additives Bulk Storage and Pneumatic Conveying
•Programmable Control Systems

5. Overview of system

6. 1. Vibratory Shakeout Machine 2. Vibratory Conveying Shute 3. Hanging Magnetic
Separator 4. 8.11.14.22. Bucket Elevator 5. Vibrator Feeder 6. Crushing and Reclamation
Machine 7. Magnetic Separator 9. Roasting Furnace 10. Rubbing Reclamation Machine
12. Centrifugal Reclamation Machine 13. Vibratory Hot Cooling Bed 15. Sand Temperature
Regulator 16.18.19.20.21. Pneumatic Transportation Device 17. Chromite Sand Separation
System
Over Viewof System

7. Belt and Bucket Conveyor Description and Details
A BUCKET ELEVETOR can
elevate a variety of bulk
materials from light to heavy
and from fine to large lumps.
BELT CONVEYORs are typically
used in fixed installations for
transportation of large volumes of
abrasive media from easy
accessible areas .

8. Storage Chamber
• Storage chamber is the
main source of providing
Foundry sand in
moulding zone and within
it sand stay with its
proper idle Properties.
• Size of its depend on the
demand and quantity
products of Industries.

9. SAND DRYER
Raw sand contains dust,
pebbles moisture and other
contaminants. And cannot be
directly mixed with other
additives and binders. Hence,
it needs to be treated to obtain
the desired grain size and
consistency. Sand dryer is a
kind of equipment to dry large
amounts of material. As it's
reliable operation, operating
flexibility and adaptability, large
capacity per unit area, it’s
widely used in building
material, metallurgy, chemical,
coal, mining industry.

10. Mixing Chamber
Mixer bowl
Wall scraper
Turbine
Turbine drive
Rotating arm drive
Plough
Sand outlet
Prepared sand
Weighing hopper , sand
Used sand
New sand
Weigh hopper, additives
Sand Multi-controller
Guide vane
Prepared sand hopper
Discharge gate

11. Introduction to Moulding and Moulding Machine
Fundamentally, a mold is produced by shaping a refractory material to form a cavity of
desired shape such that molten metal can be poured into the cavity. The mold
cavity needs to retain its shape until the metal has solidified and the casting is
removed.
Molding machine may be classified as follow on the basis of method of compaction:
1. Squeeze moulding 2. Jolt moulding 3. Jolt-squeeze moulding 4. Slingers
5. Blowers 6. Air flow and squeeze

12. Classification of Green Sand inMoulding Processes

13. Moulding Process
DISAMATIC consists of a molding machine and mold transporting conveyor (A molding sand
mixture, usually green sand or bentonite) is blown into a rectangular steel chamber using
compressed air. The molding sand is then squeezed against two patterns, which are on the two
ends of the chamber. After squeezing, one of the chamber plates swings open and the opposite
plate pushes the finished mold onto a conveyor. Finally, any cores are automatically set into the
mold cavity while the next mold is being prepared.

14. Pouring
When manufacturing by metal casting, pouring refers to the process by which the
molten metal is delivered into the mold. It involves its flow through the gating system
and into the main cavity (casting itself).

15. Shaking
Mould shake out equipment and Shaking conveyor belt has special model of
Vibrating shake-outs or knock-outs to meet the industry needs for green and
process and also that of resin sand process. Right value of vibration force,
amplitude and frequency are key to achieving required mould characteristics.

16. Filtering
Three-Chamber Underground Sand Filter
The first chamber acts as a pretreatment facility removing any floating organic material such
as oil, grease, and tree leaves.
The second chamber is the filter chamber. It should contain three feet of filter material
consisting of gravel, geotextile fabric, and sand, and should be situated behind a three foot weir.
The third chamber is the discharge chamber. It should also receive the overflow from the first
chamber through the bypass pipe when the storage volume is exceeded.

17. Refining of Return of Sand and Testing
This Process goes following steps-
1.Crushing and regeneration of used sand;
2.The used sand containing a large amount of fine dust is subjected to dedusting and
cooling;
3.Conveying of new and used sand;
4.Sent to the bucket after being mixed with the new sand according to a proportion;
5.After that sand sample is Tested and there after it is sent to Storage chamber for
further use.

18. REFINEMENT PROCESS

19. Properties of Foundry Sand
Foundry Sand is high quality silica sand that is a by-product from the
production of both ferrous and nonferrous metal castings. The physical
and chemical characteristics of foundry sand will depend in great part on
the type of casting process and the industry sector from which it
originates.
Property Results Test Method
Specific Gravity 2.39 - 2.55 ASTM D854
Bulk Relative Density, kg/m3 (lb/ft3) 2590 (160) ASTM C48/AASHTO T84
Absorption, % 0.45 ASTM C128
Moisture Content, % 0.1 - 10.1 ASTM D2216
Clay Lumps and Friable Particles 1 - 44 ASTM C142/AASHTO T112
Coefficient of Permeability (cm/sec) 10-3 - 10-6 AASHTO T215/ASTM D2434
Plastic limit/plastic index Nonplastic AASHTO T90/ASTM D4318

20. Future Scope
Reducing Foundry Sand
Reducing foundry sand was continues to be a major costsaving opportunity area for many
foundries. New formulations of binder materials increase the useable life of foundry sand. Sand
recovery and reuse processes incorporate effective capture and segregation of unwanted materials
from the waste sand stream. Effective capture systems make recovery less cumbersome and more
profitable.
Foundry sand management options:
• re-plumb the dust collector ducting on the casting metal gate cutoff saws to collect metal chips for
easier recycling;
• install a new bag house on the sand system to separate the sand system dust from the furnace
dust;
• install a new screening system or magnetic separator on the main molding sand system surge
hopper to continuously clean metal from the sand system;
• separate nonferrous foundry shot blast dust (often a hazardous waste stream) from other non-
hazardous foundry and sand waste streams;
• install a magnetic separation system on the shot blast system to allow the metal dust to be
recycled;
• change the core sand knockout procedure to keep this sand from being mixed in with system
sand prior to disposal.

21. Sand Reclamation
Pollution Prevention Methods for Foundries
Sand Reclamation
Attrition Sand Reclamation
Attrition sand reclamation technology spins two streams of sand in
opposite directions in the presence of heat. The combination of
sand abrasion and binder combustion free the sand particles from
some binders. Attrition cannot remove all residual binders, but
works well with no-bake binders. The yield from this process is a
high strength recycled sand.
Dry Sand Reclamation
Dry sand reclamation relies on mechanical and pneumatic
scrubbers to remove lumps and binders from sand (Figure 5).
Mechanical scrubbing moves each sand grain through a sand-to-
metal or sand-to-sand interface to remove impurities. Pneumatic
scrubbers use air to propel sand between baffles. These scrubbers
are particularly good for removing clay from molding sands and
binders in systems that are not baked.

22. Sand Reclamation continued
Water (Wet) Reclamation
Wet reclamation uses water to remove sand binders (Figure 6). The
process uses on the different water solubilities of sand and binders to
separate the two. Clay bonded systems work well with water
reclamation processes because the clays are very soluble in water.
Sodium silicate sand binders can also be removed using wet
reclamation. The sodium silicate dissolves part of the sand crystal
when binding, but can be removed by exposing it to water. After the
sand is soaked in a water bath it is dried and reused.
Thermal Sand Reclamation
Thermal reclamation uses heat in a rotary kiln, multiple-hearth
furnaces, or a fluidized bed to combust binders and contaminants
(Figure 7). In removing binders, the process can cause sand to change
in composition. Combustion products from the fuel used to heat the
sand and thermal cracking of the sand crystals may occur. The
resulting sand may be significantly different than the original sand.
Depending on the type of casting, thermally treated sand may or may
not be usable.

23. SandReclamation
CONTINUED
Sand Recycling
Another option for foundry sand is recycling. Many industries use sand as a
raw material in their processes. As foundry sand is usually not hazardous, it
can serve this purpose. Markets for spent foundry sand include
manufacturing of: cement, concrete, asphalt, bricks and tiles, flowable fill
(permeable, low-strength concrete), geotechnical fill and roadfill, daily landfill
cover, and manufactured topsoil and composting. Liability and local
legislation must, of course, be considered before selling spent foundry sand.
Spent Slag and Emissions Control Dust
Slag and emissions control dust constitute the remainder of the solid waste
produced by foundries. Not much has been written regarding process
modification to reduce these solid wastes. However, if the slag or dust
contained sufficient metal content, they can be fed back into the furnaces to
reclaim the remaining metal dust. The metals can also be recovered from the
dust using electrolytic or other metal recovery techniques. The recovered
metal can either be added to the molten metal or sold for other uses.

24. Conclusion
Metal casting industry is a Mother industry. Most of industries use
cast metal components in some form or another. Industrial revival,
after steep recession, has given a boost to foundry industry.
Improvement in infrastructure and power generation in particular
shall further increase demand of castings. After service sector’s
record growth in the last decade, manufacturing sector is poised
to have accelerated growth now due to it’s potential to offer
employment to growing population. This will obviously, result in
increased demand of castings for sustained and increased growth
of economy.
This increase in demand directly relate to the fact that the
requirement for a proper sand flow system has an important role
to play in the foundry industry. In the decades to come the
foundry industry will provide a fare amount to the economy of the
country.