Each injection molded product must first determine its mold opening direction and parting line at the beginning of the design to ensure that the core slider mechanism is minimized and the impact of the parting line on the appearance is eliminated.
1. After determining the mold opening direction, the product's reinforcing ribs, snaps, protrusions and other structures are as close as possible to the mold opening direction to avoid the core reduction and the mold life is longer.
2. After determining the mold opening direction, you can select the appropriate parting line to avoid the reverse buckle in the mold opening direction, thus improving the appearance and performance.
Second, the draft angle
1. Appropriate drafting angle can avoid product pulling (drawing). The smooth surface of the draft should be ≥ 0.5 degrees, the surface of the fine grain (sand surface) should be greater than 1 degree, and the rough surface should be greater than 1.5 degrees.
2, the appropriate draft angle can avoid the top of the product injury, such as white, top deformation, burst.
3. When designing the deep cavity structure, the slope of the outer surface should be as large as possible to the slope of the inner surface to ensure that the core is not biased during the injection process to obtain a uniform product wall thickness and to ensure the strength of the material product opening.
Third, the product wall thickness
1. All kinds of plastics have a certain wall thickness range, generally 0.5~4mm. When the wall thickness exceeds 4 mm, the cooling time is too long, resulting in shrinkage and the like, and the product structure should be considered.
2, uneven wall thickness will cause the surface to shrink.
3, uneven wall thickness will cause pores and welds.
Fourth is reinforcement
1. Reasonable application of ribs can increase the rigidity of the product and reduce deformation.
2. The thickness of the ribs must be ≤ (0.5 ~ 0.7) T product wall thickness, otherwise the surface will shrink.
3. The slope of the rib should be greater than 1.5° to avoid head injury.