Taizhou Huangyan Jiucheng Mould Factory

Small flower pot mold manufacturer | Huangyan small flower pot mold manufacturer | Taizhou small flower pot mold manufacturer
Mold name Small flower pot mold manufacturer
Mold type Injection mold Mold life according to contract Packaging method Wooden box Processing cycle Days After-sales maintenance Free maintenance Trademark Jiucheng mold Process combination type Single-process mold Mold installation method Fixed mold product category Industrial product Forming method Injection molding mold product material Steel Injection molding process description Mold is a kind of production of plastic products tool. It consists of several groups of parts. There is a molding cavity in this combination. During injection molding, the mold is clamped on the injection molding machine. The molten plastic is injected into the mold cavity and is cooled and shaped in the cavity. Then the upper and lower molds are separated and the product is ejected from the mold cavity and out of the mold through the ejection system. Finally, the mold is closed again for the next injection molding. The entire injection molding The process is cyclical.
Common problems and solutions in molds
Cracks are a common defect in plastic products. The main reason is due to stress deformation. There are mainly residual stress, external stress and stress deformation caused by the external environment.
Cracks caused by residual stress
Residual stress is mainly caused by the following three situations: overfilling, demoulding, and metal inlays. As a solution to cracks caused by overfilling, we can mainly start from the following aspects
Since the pressure loss of the sprue is minimal, if the cracks mainly occur near the sprue, you can consider using multiple Point distribution point gate, side gate and handle gate method.
Under the premise of ensuring that the resin does not decompose or deteriorate, appropriately increasing the resin temperature can reduce the melt viscosity and improve fluidity. It can also reduce the injection pressure to reduce stress.
Generally, when the mold temperature is low, stress is likely to occur and the temperature should be increased appropriately. However, when the injection speed is high, the stress can be reduced even if the mold temperature is lower.
Excessive injection and pressure holding time will also produce stress, so shortening it appropriately or switching the pressure holding time will have a better effect.
Amorphous resins such as resin resin are more likely to produce residual stress than crystalline resins such as polyethylene and polyformaldehyde, so attention should be paid to them.
Due to the small draft of the mold and the roughness of the punch during demoulding and pushing out, the pushing force is too large to produce stress, and sometimes even whitening or cracking occurs around the pushing rod. The cause can be determined by carefully observing the location of the crack.
When inserting metal parts during injection molding, stress is most likely to occur and cracks may occur after a period of time, which is extremely harmful. This is mainly due to the huge difference in thermal expansion coefficients between metal and resin, which creates stress and over time the stress exceeds the strength of the resin material that gradually deteriorates, causing cracks. In order to prevent the resulting cracks, as a rule of thumb, general-purpose polystyrene with wall thickness and outer diameter of embedded metal is basically not suitable for adding inserts, and inserts have the least impact on nylon. Due to the small thermal expansion coefficient of glass fiber reinforced resin materials, they are more suitable for embedded parts.
In addition, preheating the metal insert before molding also has a good effect.