What are the requirements for home appliance mold processingDue to the long processing time, the influence of ambient temperature must also be considered. For example, when machining large molds on ordinary machine tools, a change in ambient temperature of 10°C will cause the temperature in the machine column to change by 6°C, so that the parallelism of the spindle angle plate will change by 0.07 mm. Therefore, the machine design must consider the influence of ambient temperature to avoid the influence of ambient temperature on the accuracy of machined parts.
The mold drawing should include two floor plans and a vertical cross-sectional drawing, especially cut as many shapes as possible from products with large horizontal and high differences in pillow height, and draw the pillow line of the product in the floor plan. The precision of the mold, that is, avoiding jams, guide columns, pins, etc., depends on the appearance quality of the product, the quality and life of the mold. According to the mold structure, various methods are selected, which mainly depend on the control of machining accuracy, and the internal model is mainly used for design. This method has been fully considered by the teacher and is well designed and easy to adjust.
(2) Preheating. Depending on the material and requirements of the mold part, preheating processes such as annealing, normalizing, or quenching and tempering are used to improve the structure, eliminate structural defects of the forged blank, and improve the machining process. High carbon alloy cast steel can remove network secondary cementite or chain carbides, spherical and refined carbides, and even make carbides evenly distributed by proper preheating. This will help ensure the quality of quenching and tempering and improve the life of the mold.
The important parameters that determine the size of the product at a constant molding temperature are the holding pressure, and the important variables that affect the dimensional tolerance of the product are the holding pressure and temperature. For example, the holding pressure decreases immediately after the filling is completed, and when the surface layer forms a certain thickness, the holding pressure increases again, so that large products with large walls are formed with low clamping forces, sagging and flash can be removed.
Injection pressure control is usually divided into one injection pressure, two injection pressures (holding pressure) or three or more injection pressure control. Correct pressure changeover time is important to prevent excessive pressure on the mold and to prevent spillage or material shortage. The specific volume of the molded part depends on the melt pressure and temperature at which the gate is closed during the hold step. Each time you switch from holding pressure to the cooling phase of the product, if the pressure and temperature are the same, the same amount of pressure does not change.
Due to the excessive processing time, the influence of ambient temperature must also be taken into account. For example, when machining large molds on ordinary machine tools, a change in ambient temperature of 10°C will cause the temperature in the machine column to change by 6°C, so that the parallelism of the spindle angle plate will change by 0.07 mm. Therefore, the machine design must consider the influence of ambient temperature to avoid the influence of ambient temperature on the accuracy of machined parts.
