Factors affecting injection molding: time control

author: Universe plastic

2024-03-23

In the process of injection molding, time control is crucial, which will affect the quality of the entire finished product. If you want to do high-quality injection molding processing, in addition to skilled operations, you must also have the ability to control processing time.

Because if the time of some injection molding steps is not controlled well, there may be problems in the products produced. So in what aspects should we control our time? Universe Plastic Engineer will explain to you in detail:

Injection molding machine settings panel

What time factors affect injection molding?

1. Injection molding pressure holding time

The pressure holding time of most injection moldings is about two seconds, but it can be longer depending on the specific situation. Too short may lead to problems such as inaccurate plastic dimensions and poor surface quality.

2. Cooling time

The cooling time during injection molding should be set according to the product shape and cooling efficiency. Most cooling times are longer than the heating time. It is necessary to ensure that the product is fully cooled and solidified before the mold can be opened.

3.Injection time

The injection time refers to the time for the plastic melt to be injected from the screw into the mold cavity. If it is too short, it may lead to under-injection or bubble defects. If it is too long, it may cause material degradation and affect the mechanical properties and appearance quality of the product.

4. Pressure holding time

The holding time refers to continuing to apply injection pressure after the injection is completed. If it is too short, it may cause injection shrink marks and dimensional instability. If it is too long, it may cause the material to wear the mold.

5. Cooling Time

Cooling time refers to the time for the plastic melt to cool and solidify in the mold. If it is too short, the product will not be completely solidified and will be deformed or damaged when taken out. If it is too long, it will affect production efficiency.

6. Screw pre-plasticizing time

The pre-plasticizing time refers to the time for the screw to heat the mixed plastic particles to melt evenly. If it is too short, it will cause unmelted material or poor filling in the injection molding. If it is too long, it will cause the plastic melt to degrade and affect product performance.

7. Screw retreat time

The screw retraction time refers to the time to prepare for the next injection after completing an injection operation. Too short will affect the next injection molding effect, and too long will affect production efficiency.

8. Mold opening time

The mold opening time refers to the time from the closed state to the complete opening of the mold. If it is too short, it will damage the mold or the product, and if it is too long, it will affect the production efficiency.

9. Mold closing time

The mold closing time refers to the time from the open state to the complete closing of the mold. If it is too short, the mold will not be completely closed, causing flash or poor injection. If it is too long, it will affect production efficiency.

Comprehensive impact of time factors on injection molding quality

1. Improper time control will lead to unstable product size and affect assembly and function.

2. Unreasonable settings of injection, holding pressure, and cooling time will cause surface defects, such as flow marks, sink marks, bubbles, etc.

3. Too short cooling time will cause internal stress to increase and affect the mechanical properties and service life of the product.

4. Unreasonable settings of pre-plasticizing time and holding time will cause material degradation and affect the mechanical properties and weather resistance of the product.

5. Time control directly affects the production cycle. Reasonable time control can improve production efficiency and reduce production costs.

Optimize time parameters

1. Determine the best time parameter settings through mold trial and process debugging.

2. Monitor injection molding parameters in real time during the production process and make adjustments according to actual conditions.

3. Optimize the mold design, such as improving the cooling system, increasing cooling efficiency and reducing cooling time.

4. Regularly maintain and maintain injection molding equipment to ensure its stable operation and reduce time delays caused by equipment failure.

Summarize

In the injection molding process, the time factor has a significant impact on the quality of the final product. The time control of the injection molding process requires comprehensive consideration of multiple factors, including material properties, product design, and process parameters, and requires continuous accumulation of experience and adjustment and optimization through practice.

Dongguan Universe Plastic Factory suggests that by reasonably controlling and optimizing the time factor in the injection molding process, the quality and production efficiency of injection molded products can be significantly improved.

If you have injection molding needs or questions, feel free to contact us.

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