The advantages and disadvantages of green sand casting process
Let me briefly introduce the advantages
and disadvantages of green sand casting process in China dandong
foundry, and hope
it could be helpful for casting buyers to learn more about its
In China, green sand casting process is very common, and almost all
iron foundries could
produce iron castings by this
process. Its mainly because of the advantages of this process.
1. Simple production process
The production process of green sand
casting is very simple comparatively, so easily handled. The
materials are simple, and easily available.
2. Lower production costs
Since the materials are simple and its
prices are lower comparatively, the production costs of green sand
casting are lower. Therefore, the green sand castings are cheaper
than resin sand castings and shell molding castings. As for the
current cast iron prices,
you could check the website of
3. Higher production rate
The green sand casting process can
achieve high production rate. The floor molding with green sand can
produce castings of 100 to 200 sand boxes each day, e.g. about 100
pieces to 2000 pieces each day. The
automatic molding process with green sand can produce
castings of 20 tons each day.
Moreover, green sand casting process can produce the castings with
unit weights from hundreds of grams to several tons.
The disadvantages of green sand casting process is also inevitable.
1. More casting defects
Green sand mold is a kind of soft mold, so it is not hard enough as
the resin sand molds and shell molding. So, there are more
casting defects such
as sand residuals, sand holes, air holes and shrinkages.
2. Rough surface quality
The casting surfaces by green sand casting process are very rough
and coarse. If the iron foundries use the very fine green sand, the
rough surfaces will be better. However, there are few iron foundries
who use very fine green sands in China. Refer to iron-foundry.com.
3. Bad casting dimensions
Since the green sand will have larger shrinkage, the casting
dimensions will have larger changes during molding and cooing
periods. Therefore, the green sand casting process will cause larger
dimensional tolerances. Normally, its could reach
casting dimensional tolerances
of CT10 to CT12.
4. Unstable casting quality
The temperature has some influence to the casting quality made by
green sand casting process. Therefore, the iron foundries should
keep the good temperature in cold winter. Moreover, as the manual
floor molding, the worker's skill will have key affects to the