1. The mold design must consider the control of the mol […]
1. The mold design must consider the control of the mold temperature of the mold product; when the designed mold has a small injection weight but a large mold size, the heat transfer in the mold structure is very important; the flow path of the mold coolant should be stable. Try not to use quick couplings, otherwise it may hinder the flow of mold coolant; when pressurized water is used as mold coolant, hoses and manifolds must be able to withstand high pressure and high temperature; select a suitable mold temperature controller, as indicated in the data sheet Indicate the cooling medium and flow rate; use insulation materials between the mold and the cavity plate of the molding machine; use different temperature control systems for the core and cavity; use different temperature control systems for the mold cavity and core, Therefore, when the mold is running, different cooling temperatures will occur.
2. The actual temperature of the mold surface contacting the plastic can be measured by a thermocouple in the mold, or more commonly by a handheld thermometer. The surface probe of the thermometer must be able to respond quickly, and the mold temperature needs to be measured at multiple locations instead of one location on each surface. Then modify the temperature control system to adjust the mold temperature to the desired level. The recommended mold temperature usually provided in the data sheets of various raw materials is the best mold temperature for the molded product to achieve the best surface finish, mechanical properties, shrinkage rate and cycle time.
3. When molding precision, optical and safety parts, it is usually best to choose a higher mold temperature (to make the molded parts have low shrinkage, smooth surfaces and uniform materials); for parts with lower technical requirements, usually choose Lower mold temperature to minimize production costs. Pay attention to the defects generated in the low temperature molding process, test the strength of the parts, and confirm that they meet customer requirements.