When designing the mold, the position and size requirements of the gate are relatively strict. After the initial mold trial, further modifications to the gate size are needed. Regardless of the type of gate used, its opening position has a significant impact on the molding performance and quality of the plastic part. Therefore, selecting the reasonable opening position of the gate is an important link to improve quality, and the different gate positions also affect the mold structure. In short, to ensure good performance and appearance of plastic parts, it is necessary to carefully consider the selection of gate location.

The following principles are usually considered:

1. Try to shorten the flow distance as much as possible.

2. The gate should be set at the position with the maximum wall thickness of the plastic part.

3. It is necessary to minimize welding marks as much as possible.

4. It should facilitate the discharge of gas from the cavity.

5. Consider the influence of molecular orientation.

6. Avoid spray and creep.

7. Avoid bending and impact loads at the gate.

8. Pay attention to the impact on appearance quality.