四、Cracking of tendons

Usually the cracking of the rib position is that the filling amount of the plastic is too much during the debugging conditions, or there is a burr at the rib position, the material is wrapped too tightly, the plastic is deformed when the product is demolded, and the rib position will be plugged in serious cases.

At the same time, if the amount of glue is too small and the fullness of the product is not reached, cracking will also occur.

There is also a situation that when the mold is designed, there is no draft of the rib position or the draft angle is too small, and the difference between the upper and lower sections of the rib depth is inversely proportional to the holding force, and cracking at the rib position will occur.

五、Dissolution marks and cracking

Cracking at the end of the product is the most common problem, which is caused by the melt filling the mold cavity, when the melt fills the mold cavity, two or more strands at the front end of the melt are fused together, and when they collide, they will merge into a joint (groove), which is a three-dimensional space formation.

Often, the dissolving line is not well bonded due to insufficient glue feed and too low temperature.

This problem is particularly obvious for brittle or sensitive materials, PS\PC transparent with a small bright line, cracking consequences are very serious, directly affecting the quality and life of the product.

Sometimes this situation is encountered, the product has reached the filling amount, there is no other defect there is a little crack, if the glue will be added to produce too many scratches, at this time increasing the mold temperature will have a better effect.