Under the premise of meeting the product function, the die castings are reasonably designed, the die casting mold structure is simplified, the die casting cost is reduced, the die casting defects are reduced and the quality of die casting parts is improved. Since the injection molding process is derived from the casting process, the die casting design guide is very similar to the plastic parts design guide in some aspects. For detailed die casting part design, refer to the book "Design Guide for Manufacturing and Assembly Products" published by the Machinery Industry Press.
Fillet
(including corners) The casting drawing often indicates the requirements of unfilled corners R2 and so on. When making the mold, we must not ignore the role of these unmarked fillets, and never make them clear corners or too small fillets. Casting fillets can make the metal liquid fill smoothly, so that the gas in the cavity is discharged in sequence, and can reduce stress concentration and extend the service life of the mold. (It is also not easy for the casting to crack at this place or various defects due to improper filling). For example, there are more clear corners on the standard oil pan mold. Relatively speaking, the brother oil pan mold is the best at present, and there are more heavy oil pans.
Demolding slope
It is strictly forbidden to have artificial side concave in the demolding direction (often when the casting is stuck in the mold during the mold trial, and when it is handled by incorrect methods, such as drilling, hard chiseling, etc., it causes local concave).
Roughness
The molding parts and pouring system should be carefully polished as required, and should be polished along the demolding direction. Since the entire process of the molten metal entering the pouring system from the pressure chamber and filling the cavity only takes 0.01-0.2 seconds. In order to reduce the resistance of the molten metal flow and minimize the pressure loss, the surface finish of the flow needs to be high. At the same time, the heating and erosion conditions of the pouring system are relatively severe. The worse the finish, the easier it is to damage the mold.
Hardness of the molding part of the mold Aluminum alloy: about HRC46° Copper: about HRC38° During processing, the mold should leave a margin for repair as much as possible, make the upper limit of the size, and avoid welding.
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