Casting – Create geometries with minimal material waste
The casting process involves melting a material (usually a metal) into a mold to get a finished component. There are many different casting methods and what is right for you depends on what you want to achieve.
A casting process consists mostly of six steps: Mold making, melting of material, casting, solidification, clearance and possible finishing. The most common materials that are casted are different metals and alloys but you can also cast materials like plastic, concrete and glass.
When casting, the molds can be filled manually or automatically. In order to maintain cost efficiency, automatic use is usually used for large volumes. If you have low volumes, manual handling is usually preferable, because it does not pay to invest in robots.
The most common methods for metal casting are die, sand and precision casting. Which one is the most suitable for you depends on your needs.
Precision casting is the method we work most with at ESMA. Precision casting allows you to cast smaller components (usually in steel), with complex geometries and good surface finish. The method briefly means that a wax model of the same geometry as the finished castings is created. It is immersed in a ceramic pulp and then burned to a ceramic mold. When the component is solidified, the mold is shaken off with vibration. Precision casting, together with sand casting, is the only possible option if you want to cast steel or stainless steel. Precision casting gives you more accurate measurements, which reduces processing and thus also your costs. The method is often used in the automotive industry and for example for pumps and valves in the process industry.
Pressure casting is used for metals with lower melting points, such as aluminum, magnesium, zinc, but also lead and tin are possible materials. The material is pressed into a mold under high pressure and then pressed together. Pressure casting, like precision casting, provides a good surface finish, but requires higher volumes to be cost-effective because of the tool costs.
Sand casting is used for large castings. Since the method requires manual work it is most advantageous for lower volumes. By sand casting, a cavity in sand is used and this is destroyed after the casting process. The method is mostly used for steel and aluminum components but also works for reddish alloys. Sand casting often requires some form of mechanical post-processing.
Chill casting is based on casting in static steel molds. The method is most suitable for metals with lower melting points (like aluminum), and offers the possibility of complex geometries through inserts of, for example, cores in the casting tool. Major applications include cylinder head lid in the automotive industry. Chill casting requires a good overview of the material to minimize pore formation.
Castings are often used in components for the engineering, automotive and construction industries, but also in household products.
Depending on the geometries you want to achieve, you can significantly reduce your manufacturing costs by casting if you have a component with complex geometry. Casting gives you many exact measurements, without material waste and with limited need for post-processing.
Advantages of casting
The biggest advantage of casting is that you can create a geometry with minimal machining and without material waste compared to for example cutting processes.
Precision casting gives a lot of freedom in geometry, compared to other casting methods, as you do not need to take tractions and draft angles into account. The tool cost is relatively low which makes the method suitable for smaller production series.
ESMA’s manufacturers and suppliers
In our network of manufacturers, we cooperate with foundries in Europe and Asia. As many casting processes are staff intensive, we have established ourselves in LCC countries to offer cost-effective products.