What should I do if there is a dark area near the material head during injection moulding process?

In the injection moulding process, sometimes there is a dark area near the head, which not only affects the quality of the product, but also may lead to lower production efficiency. So, in the face of this situation, how should we solve it?

We need to understand the reasons for the dark zone near the material head. Generally speaking, there are several main reasons for the dark zone near the injection moulding head:

1. raw material problems: raw materials contain impurities or too much water, resulting in poor melt fluidity, easy to appear dark zone.

2. Temperature control problem: the temperature control of the injection moulding machine is not stable, resulting in low temperature of the melt near the head, which makes the melt have poor fluidity and is prone to dark zones.

3. Insufficient injection pressure: Insufficient injection pressure will lead to insufficient filling of the melt in the mould, which is prone to dark areas.

4. Mould design problem: The unreasonable design of the mould, such as the irrational design of the gate, will easily lead to the poor flow of the melt near the head, and dark zones will appear.

Understanding the reasons for the dark zone near the head, we can target the solution:

1. Optimisation of raw materials: Choose high-quality raw materials, strictly control the purity and moisture content of raw materials to ensure the fluidity of the melt. At the same time, regular testing of raw materials to ensure stable quality of raw materials.

2. Stabilise the temperature: Adjust the temperature control parameters of the injection moulding machine to keep the temperature of the melt near the head in a stable range. At the same time, strengthen the maintenance of the temperature control system of the injection moulding machine to ensure the precision and stability of temperature control.

3. Increase the injection pressure: According to the actual production situation, increase the injection pressure appropriately so that the melt can fully fill the mould. At the same time, regularly check the stability of the injection pressure to ensure the precise control of the injection pressure.

4. Improve the mould design: Improve the mould for the problem of dark area near the material head. For example, optimise the gate design to make the melt flow more smoothly near the head; increase the cooling water circuit to improve the cooling speed of the melt near the head, so as to reduce the generation of dark zone.

5. Optimise the production process: under the premise of ensuring product quality, optimise the production process, shorten the injection cycle and improve production efficiency. Such as the use of multi-stage injection, slow injection and other technologies to improve the fluidity of the melt and reduce the generation of dark areas.