HEATERS FOR INDUSTRIAL FURNACES: DIE CASTING AND FOUNDRY INDUSTRY
Among the products of MDR Marca dedicated to die-casting process and the foundry industry, the production of heaters for industrial furnaces is very significative.
The die casting process, also called under pressure shell foundry, provides the use of different types of furnaces, depending on the type of process undertaken.
In the process of shell mold foundry, the mold consists of two half-molds generally made of steel or cast iron. As result, the metals used during this process will be materials which melt at lower temperatures, such as alloys of aluminum, zinc or magnesium.
During the process of shell casting mold, the injection pressure of the molten metal can vary from 2 to 150 MPa depending on the case. The pressure is maintained during the process until the glass solidification, while hydraulic presses guarantee the closing of the mold also at high operating pressures. When the piece has solidify and cooled, the presses open the two molds so that it can be withdrawn.
This process is highly automated, and therefore allows to obtain high productivity. The nature of the molds also can produce pieces that have a dimensional tolerance and a finish surface better than other foundry processes. However, the initial installation costs are very high and recoverable only for large productions.
The die casting process can be divided into two main categories:
The hot-chamber die casting, thanks to the presence of the furnace, ensures better control of the operating temperature and high production rates. The direct withdrawal from the tank makes the process faster and, thanks to the fact that the tank is larger, the alloy is more uniform in terms of composition and temperature than the cold chamber die. Consequently, also the structure of the product will be more homogeneous.
On the other hand the process temperature can not reach too high levels to avoid compromising the productivity that requires restrained cooling times. This limites the application of the pressacolata hot chamber to metals with low melting point.
The holding pressure of this process is lower than the cold chamber and ranges from 2 to 15 MPa.
During the process of die casting the metal is cast into a shape composed of two metal under pressure half-molds, which usually are made of steel, cast iron or any other material to fusion temperatures definitely high. For this reason the materials cast within the mold must necessarily possess a melting temperature lower than the steel.
Compared to the shape of the ground foundry, the mold for die casting can boast thin thicknesses (up to 1 mm) thanks to an easier filling due to high pressure. On the other hand, the mold must be free of missive areas (parts of the object much larger than all the other) to allow a uniform cooling of the piece.
The extraction from the mold is simpler than the ground foundry and, having only two molds, you will have to use the blocks to prevent possible undercuts. At the time of extraction the piece will be integral with the mobile part of the mold, in order to facilitate a quick exit.
The process of cold chamber die has a lower temperature control of the liquid jet and then a lower productivity because of the longer times due to the inclusion of the molten metal, and in particular at the operating temperature substantially higher. However, the cold chamber process compensates the lower productivity with a greater flexibility of materials.
In the die casting process can be used various types of furnaces and of heaters for industrial furnaces:
In addition to the heaters for industrial furnaces, MDR Marca offers its customers a lot of products for the die casting process: discover them all by visiting the “Products” section of our website.