Radiation pattern problem in injection molding: causes and solutions

There are a number of quality issues that may arise in injection molding production, one of which is radial pattern. So, what is radial grain? How is it produced? And how do we solve this problem?

Radiation pattern refers to the surface of plastic products appear similar to the sun's rays of the stripe-like texture, these textures along the injection direction of the product extends, forming a radial pattern. The appearance of radiation pattern will affect the appearance quality of the product and reduce the added value of the product.

How do radial lines occur? The main reasons are as follows:

1. Uneven mold temperature: If the temperature of the mold is not uniform, it will lead to uneven flow of plastic in the filling process, thus forming radiation pattern.

2. injection speed is too fast: injection speed is too fast will lead to the plastic in the mold filling is not sufficient, the formation of voids and bubbles, which in turn leads to the generation of radiation pattern.

3. insufficient holding time: insufficient holding time will make the plastic can not fully fill the mold, the formation of radial lines.

4. Plastic material problems: If the plastic material has poor fluidity or contains impurities, it is also easy to lead to radiation pattern.

Understanding the causes of radiation pattern, we can target the solution. Here are some suggestions:

1. Optimize the temperature of the mold: Ensure that the temperature of each part of the mold is evenly distributed, which can be adjusted by heaters or cooling systems. At the same time, the temperature of the mold can be increased appropriately to improve the flow of plastic.

2. Adjust the injection speed: According to the shape and size of the product, choose the injection speed reasonably. For complex geometrical shapes, slow-fast-slow injection can be used to minimize the generation of radial lines.

3. Extend the holding time: extend the holding time appropriately, so that the plastic fully fill the mold to eliminate voids and bubbles, thus reducing the generation of radiation pattern.

4. Choose the right plastic material: choose the plastic material with good fluidity and less impurity, which can effectively reduce the generation of radiation pattern.