There are now numerous technical molding for parts by casting. Among the most important stand out:
• Molding green-sand
• Molding chemical-sand
• Molding Shell (Shell)
• Lost-wax casting
• Casting of metal shell
• Vacuum Molding
• Spin molding.
You can not define a technique as better as or worse than another. Each has its advantages and disadvantages and each smelter must select the molding technique that best suits your needs, taking into account the following parameters:
• Type of metallic material
• Design of the part to be manufactured and requirements
• Operational characteristics of the plant
• Size of the series to be produced
Analyzing all these aspects Cofundi has chosen to use the techniques of green sand molding, chemical sand molding and casting in metal shell.
Sand casting, both green and chemical, is a well known and highly developed technology which utilizes a very cheap material (sand) which is capable of withstanding the high temperatures of aluminum casting technique. The preparation of molds and thus obtaining parts is done very quickly, optimizing the productivity of the casting. To these positive factors, we add that most of the sand used can be reused in the circuit.
Cofundi sand opts for chemical in large pieces that are not possible in the carousel green molding sand in small batches or harsh demands references with regard to its geometry.
Instead he opts for green molding sand in medium or large series of small to medium pieces.
The metal shell molding provides excellent surface finish and a high speed of manufacture of the parts. Also the cooling rate of the cast material is greater than that which occurs in other molding techniques. In the case of aluminum this aspect is critical to get good mechanical properties.
Cofundi opts for this technique, medium or large series, with demanding requirements of surface quality or mechanical properties.
Each piece and each order must be studied, to choose the most suitable molding technique, in order to maximize plant productivity and meet customer requirements.