Consider these 8 things in Order to Produce Quality Castings
Whether your product is produced on a vertical or horizontal centrifugal casting machine, your centrifugal casting process must include the following items! If you are getting defects and your machine foundation is sound, the solution is likely found in better control of one or more of the below operations.
- Speed Control. The machine must be able to accelerate the mold to a pre-determined speed, maintain smooth spinning and decelerate to a stop in a reasonable time frame. The machine also should be able to change speeds during pour and solidification for some special applications.
- Heating. There must be a way to heat the mold before coating it and pouring the molten metal.
- Coating. There must be a way to coat the mold with refractory coating before pouring molten metal. This operation can be performed on or off the machine.
- Pouring. There must be a means to pour the molten metal safely into the rotating mold at a controlled rate, position and orientation.
- Cooling/Solidification. Once the metal is poured, a proper solidification and cooling rate must be established in the mold to obtain a desired casting microstructure, protect the mold and achieve required productivity. This can include a method for water cooling the spinning mold.
- Addition of Flux/Inoculants. There must be a means of adding inoculants or fluxes for some special applications.
- Extraction. There must be a means of extracting the solidified casting efficiently from the mold at elevated temperatures without deforming the casting.
- Process Control. Having a way to control spinning speeds, mold temperature, coating application, water cooling time, etc. is essential for managing casting defects. We like to say, having the machine is half the battle; the other half is controlling your process.