I believe that many friends have encountered the problem of air bubbles in the injection mold during the production process of the injection mold. Especially as a friend who has just entered the industry, it will seem helpless when facing such a problem. Let ’s analyze the injection today. Reasons and solutions for air bubbles in the mold.

First, defects in the mold design cause bubbles in the injection mold

For example: Poor injection gate position, too small gate, asymmetric gate arrangement of multi-gate parts, small runners, irrational mold cooling system, too large difference in mold temperature, etc., causing melt to be in the cavity The flow is discontinuous, blocking the passage of air.

Second, the mold parting surface lacks the necessary exhaust holes, or the exhaust holes are insufficient, blocked, or in a poor position, and there are no processing gaps such as inserts and ejectors, so that the air in the cavity cannot be simultaneously with the plastic. Leave. These reasons also cause the phenomenon of air bubbles in the injection mold.

Finally, if the surface roughness of the injection mold is poor, the frictional resistance is large, causing local hot spots, and the decomposition of the passing plastic will also cause the occurrence of air bubbles.

Of course, in addition to the mold reasons, there will also be equipment, processes, raw materials and other reasons; so every process in the production process of the injection mold needs to be very careful and serious, try to avoid the occurrence of bubbles in the injection mold and reduce product production. The bad rate in the process can increase the competitiveness of injection mold manufacturers in the increasingly competitive mold industry.