Why automatic molding is
better than green sand casting, shell molding and resin sand
Some clients may be wondering why we
suggested to produce their iron casting products by automatic
molding line, instead of manual green sand, shell molding or resin
sand casting process.
Herein, we will focus to introducing the advantages of automatic
Brief introduction of automatic molding process
Automatic molding process is also a type of sand casting process.
The green sand is its main molding material. One operator could
control the molding machine to complete the whole molding process,
so called automatic molding.
Advantages of automatic molding process
1. Because of advanced mechanical automation, all sand molds
have the same dimensions, tension, moisture content and other
properties, so the iron castings have the almost same dimensions
Manual green sand casting process is using labors to complete the
molding process, which will cause larger dimensional tolerance, big
difference of casting dimensions. Shell molding also had the problem
for dimensional difference on the parting line positions.
2. Because of high tension of sand molds, there will be
less surface defects, such as sand inclusion, air holes, sand holes
Manual green sand castings have many surface qualities, and shell
molding castings had inverse chilling defects for the thin wall
3. High production rate is also an advantage. Automatic
molding line could produce at least 10 tons each day, so it could
meet demand for large quantity or urgent orders.
Manual green sand, shell molding and resin sand casting process will
have much lower production rate.
4. The iron castings made by automatic molding line are
cheaper than shell molding and resin sand castings.
We have been in foundry production in China for over 50 years, we
have to admit that the automatic molding process is the best one.
Shell molding castings are more costly, but it is suitable for
producing complex small and middle sized castings. Resin sand
casting process is suitable for large iron castings, which are
costly too. Manual green sand is also widely used for many Chinese
foundries, and it is suitable for low or normal required castings,
but its quality will not be as good as automatic molding process.