What Is Centrifugal Casting?
Centrifugal casting or also known as rotocasting is a casting process that produces a cylindrical cast product by rotating the mold on its axis.
The casting process can be done vertically or horizontally without using a core.
The cast product produced using this method will have a directional freezing direction from the outer diameter to the inner diameter.
So that the product resulting from centrifugal casting will have several characteristics, including:
- The product has a high density, especially on the outside or the surface of the castings.
- The product does not experience freezing shrinkage on the outside due to the greater centrifugal force and works continuously on the surface.
- Impurity and slag impurities will be on the inner walls of the castings and these can be removed by machining.
How Does It Work?
Centrifugal casting is done by inserting molten metal into a mold that rotates at high-speed up to 3,000 turns per minute.
This casting technique uses centrifugal force to distribute the molten metal to the edges of the mold cavity at a pressure approaching 100 times the force of gravity.
With this technique, a thin wall cylindrical product will be produced.
Operators usually get metal from tin sheet metal suppliers as the metal used for this centrifugal casting process.
The centrifugal casting process is carried out using a special mold which consists of four parts, namely walls, pouring channels, roller tracks, endplate heads.
The mold is placed on a carrying roller which can be replaced and adjusted to adjust the mold diameter.
However, as the times became more modern, the equipment used for centrifugal casting became increasingly sophisticated.
Such as centrifugal casting equipment especially sold by METACONCEPT Group where the equipment for centrifugal casting is designed to simplify the operator’s job.
All equipment is made in a more compact size with unmatched performance which helps the operator to produce goods in low to moderate quantities.
Centrifugal Casting Speed Settings
Simply put, setting the centrifugal casting rotational speed can be divided into three stages as follows:
- In the early stages of the casting process, the mold is rotated at a speed sufficient to propel the molten metal against the mold wall.
- When the molten loam reaches the farthest end of the mold, the speed is increased.
- The rotating speed is maintained constant for some time after pouring.
The ideal rotational speed will produce a sufficiently large adhesion force between the molten metal and the mold wall with minimal vibration.
In this condition, a cast product with a more uniform structure will be produced.
If the speed is too low, the resulting cast product will have a poor surface finish.
Meanwhile, if the speed is too high it can cause vibrations which can produce circular segregation.
Additionally, too high a speed can also increase the circular tension which is quite high as well.
This can cause defects or cracks as the metal shrinks during the freezing process.