How to adjust injection molding machine parameters according to product materials?

Adjusting injection molding machine parameters according to product materials is a complex process that requires consideration of material properties and injection molding process requirements. Here are some guidelines for adjusting injection molding machine parameters based on different material properties.

1. The melt temperature setting
For thermoplastic elastomers such as TPE soft glue, the melt temperature range is usually between 150°C and 250°C. The specific temperature needs to be determined based on the data provided by the material supplier and actual operating experience.
2. The injection pressure setting
The injection pressure determines the filling and density degree of the plastic in the mold cavity. For TPE soft glue, the injection pressure is between 30 and 100MPa. The specific pressure needs to be determined based on the mold design, product structure and injection speed.
3. The injection speed setting
The injection speed determines the filling speed and filling effect of the plastic. For TPE soft glue, the injection speed should be set to fast first and then slow, that is, quickly fill the runner system first, and then reduce the speed after the material passes through the gate and begins to flow into the mold cavity.
4. Mold temperature setting
Mold temperature affects the surface finish and cooling speed of the product. High temperature can make a smoother surface finish, while lower temperature speeds up the cooling process.
5. Cooling time adjustment
Cooling time affects the time it takes for the plastic material to solidify before it is ejected from the mold. For products with simple structure, thin walls, and fast cooling, the cooling time is short. And for thick molds or thick products with relatively closed and slow heat dissipation, the cooling time is long.
6. Back pressure setting
Back pressure affects the shear heating phenomenon of the material, but too high back pressure will cause overheating and degradation of the material. The screw speed and back pressure need to be adjusted according to the actual situation to achieve the best injection molding effect.
7. Material drying process
For materials with strong water absorption, such as PA6 and PA66, it is necessary to dry them before injection molding to avoid bubbles and silver mark.
8. Consideration of material fluidity
It needs to choose the higher processing temperature if the materials have poor fluidity and high viscosity, such as PC, PMMA, PA66. For heat-sensitive materials such as PVC, POM, the temperature must be strictly controlled below its thermal decomposition temperature.
9. Matching of material properties and injection molding process parameters
Different plastic has their own different unique processing property and characteristic. The plastic performance is the basis for setting the injection molding process conditions.
10. Environmental impact factors
If sustainability is a priority, environmentally friendly or recyclable materials can be selected, such as biodegradable plastics or materials with a low carbon footprint.

In summary, when adjusting the parameters of the injection molding machine, it is necessary to comprehensively consider multiple factors such as the material melting point, fluidity, heat sensitivity, drying requirements, etc. to ensure product quality and production efficiency.