Reasonable design of castings, castings should have a uniform wall thickness, not too thin, too thick, generally about 2 to 3.5 mm thick, corners or slopes should be rounded or sloped to reduce stress concentration, and the rib structure can be used to eliminate castings. The hot section formed. Excessively thick die-casting internal coarse grains will form pores, shrinkage, oxidation, internal cracks, and will be accompanied by stressors, so that their strength and durability will be lower than those of the rib-assisted structure.
For the crack-prone and easy-to-damage parts of the mold, the insert structure is adopted as much as possible, which is easy to repair and replace after damage. However, the insert hole on the molded part, including the core hole to the edge of the mold or another hole in the vicinity, should not be too small, and the inner corner of the insert hole should have a large round chamfer, so as not to become the early turtle of the mold. The weak part of the crack.
To improve the rigidity of the mold design, it is necessary to analyze the force of each part of the mold cavity. The force obtained by the cavity is the pressure, bulging force and impact force when the alloy liquid is filled, the tensile force, the grinding force when the product is released, the thermal stress caused by the change of the temperature, the bending of the mold and the ferrule. Pressure, tension, preload, etc. The design should have sufficient thickness and width for each component and part of the mold to make the mold rigid enough to withstand various stresses. It is also important to achieve a proper balance of these forces (this is important) to prevent deformation and cracking of the mold. Pay attention to the thin section of the mold and the concave root of the module. It is a sensitive source for the mold to break. To ensure the matching precision, if the pre-tightening force of the module is too large, it will concentrate the clamping force to a point. The main factor of large-area fracture of the mold.