2 Cooling analysis of injection molds
2.1 Model establishment and preset of molding process parameters The size of the cup top cover is 500mm × 480mm × 250mm, and the thickness of the whole product is 3mm. First, use PROE to obtain a 3D model of the cupboard cover product and import it into Moldflow in the *.stl file format. Then, the parts are meshed in the Fusion format and the finite element method is used to repair the finite element. The final parameters are as follows: the number of face units = 11185, the number of nodes = 5680, and the matching rate of the unit = 79.0%. The preset process parameters for the cooling analysis are as follows: molding material selection Polyflam Rpp1058-295 (PP), mold temperature 50 ° C, melt temperature 230 ° C, mold opening time 5 seconds, injection molding pressure cooling time sum is 30 seconds, filling control The speed/pressure control is converted to automatic control, and the pressure holding control is the relationship between the filling pressure and the time, and the default value is adopted. In the cooling system, the layout of the preset cooling pipe is preset according to the plastic structure. The cooling pipe has a diameter of 10 mm; the cooling medium is water, the temperature is 25 ° C, the flow rate is 2.54 L/min; the population Reynolds coefficient It is 10000; the simulation analysis process is Cool mode. 2.2 Cooling analysis The cooling analysis is used to analyze the heat transfer in the mold, mainly including the temperature and cooling time of the plastic part and the mold. The factors that determine the performance of the cooling system are as follows: the heat transfer rate of the resin melt to the mold; the heat transfer rate from the plastic melt/metal interface to the metal/coolant interface throughout the mold; and the conduction from the metal/coolant interface to the coolant rate. That is, the heat transfer performance determines the performance of the cooling system. The factors that affect the heat transfer rate of the plastic melt to the mold wall are: material properties of the melt, such as specific heat, heat transfer capacity; temperature gradient between the melt and the mold wall. The contact properties between the melt and the mold. MPI/Cool provides users with a wealth of simulation analysis results through heat transfer analysis of molds, products, and cooling systems: (1) Cooling time. In order to ensure that the product has sufficient strength during demolding to prevent deformation after demolding, determine the appropriate cooling time; MPI / cool can calculate the cooling time required for the product to fully cure or the user set percentage of cure.(2) Temperature distribution of the cavity surface. The surface temperature of the cavity has an important influence on the quality of the product. MPI/Cool can simulate the cavity surface temperature distribution during the injection cycle, helping the process technician to determine the uniformity of the mold temperature and whether the mold temperature required for the material is reached. For the neutral surface model, MPI/Cool can also calculate the temperature drop on both sides of the product.
Previous Next
Stainless Steel Ball,Welded Pipe Ball,Stainless Steel Pipe Ball,Stainless Steel Tube Ball
Antong Valve Co.,Ltd , https://www.atvalveball.com