1, product wall thickness

(1) All kinds of plastics have a certain wall thickness range, generally 0.5 ~ 4mm, when the wall thickness exceeds 4mm, it will cause the cooling time is too long, resulting in shrinkage and other problems, should consider changing the product structure.

(2) Uneven wall thickness will cause surface shrinkage.

(3) Uneven wall thickness will cause porosity and weld marks.

2. Opening direction and parting line

Each injection molding product must first determine its opening direction and parting line at the beginning of the design to ensure that the core pulling slider mechanism is reduced as much as possible and the parting line has no influence on the appearance.

(1) After the mold opening direction is determined, the structure of the product reinforcement, buckle, bulge and so on is designed as much as possible to be consistent with the mold opening direction, so as to avoid core-pulling to reduce the stitching line and extend the life of the mold.

(2) After the mold opening direction is determined, the appropriate parting line can be selected to avoid the reverse buckle in the mold opening direction to improve the appearance and performance.

3, stripping inclination

(1) The appropriate demoulding inclination can avoid the product drawing (drawing). The release slope of the smooth surface should be ≥0.5 degrees, the surface of the fine grain (sand) is greater than 1 degree, and the surface of the coarse grain is greater than 1.5 degrees.

(2) Appropriate demoulding inclination can avoid product top damage, such as top white, top deformation, top break.

(3) When designing deep cavity structure products, the external surface inclination should be greater than the internal surface inclination as far as possible to ensure that the mold core is not skewed during injection molding, to obtain uniform product wall thickness, and to ensure the material strength of the product opening part.

4. Strengthen the tendon

(1) The reasonable application of reinforcement can increase product rigidity and reduce deformation.

(2) The thickness of the reinforcement must be ≤ (0.5 ~ 0.7) T product wall thickness, otherwise it will cause surface shrinkage.

(3) The slope of the single side of the reinforcement should be greater than 1.5° to avoid top injury.