八、 The product cracks after being placed for a period of time

There is no crack when the product is taken out, and when it is placed for a period of time, it will be found that the product has cracking, and the cracking due to the manpower damage in the process of stacking and transportation is excluded, and the big reason is that there is a hidden danger of cracking such as sharp corners and notches in the structure, and after the product is stationary, the tendency of cracking expands to form visible cracks due to environmental factors and internal stress.

九、The wall thickness of the product is uneven

When the product is ejected and demoulded or the mold is opened, the wall thickness of the product is uneven, the wall thickness has not been cooled, and the thin wall has been cooled, the wall thickness will be stretched by the thin wall, which will produce residual stress, the soft material is easy to whiten at the connection, and the rigid material is easy to crack at the connection.

In terms of process means, the mold temperature can be reduced locally in the area of wall thickness, the cooling time can also be increased, and the resistance can be reduced by spraying the release agent.

十、Material reasons

For the use of materials, the material requirements of the product design should be observed, and for the products that are not very high, the addition ratio specifications should be done when mixing the nozzle material, and it is forbidden to add the nozzle material at will and change the nozzle material ratio.

When too much nozzle material is mixed or mixed, the melt index, tensile strength and color of the plastic will change, the quality of the product will be greatly reduced, and the strength of the dissolution mark will be significantly reduced.
In serious cases, the product will be broken and disintegrated, sticking to the front mold, and plugging the rib position when the mold is opened. Therefore, the selection of materials is the basic guarantee of injection molding.