Jan 9, 2020 Viewed: 28 Tag: injection  

How to solve the problems related to mold injection molding

The monitoring during the injection molding process will directly affect the quality of the product. The injection molding defects and abnormal phenomena can finally reflect the quality of the injection molded products. We have common problems and solutions for your reference. Insufficient filling is described here. The molten plastic has been injected into the cavity of the cavity and has not been filled for cooling and hardening. This phenomenon is called insufficient filling.

Causes and countermeasures caused by machine tools: Insufficient injection ability, the machine can confirm the injection ability. Injection pressure is too low to increase pressure. The raw material temperature is low and the fluidity is poor. Confirm the temperature of the heated cylinder and increase the injection pressure. Insufficient supply of raw materials, the amount of raw materials increased. Slow injection speed increases firing rate. The nozzle resistance is large, and the hole diameter and electric heating ability are confirmed. The feed of the lead screw is not good. Manual feed. It is difficult to reduce the raw material, remove the raw material group, and reduce the inlet temperature.

Causes and countermeasures caused by the mold: soup design is not uniform, recalculation and correction. The runner gate design is too small to recalculate and expand. The cold well is blocked. Clear obstacles. Exhaust ventilation design is poor. Reduce mold temperature, lower water temperature and water. The finished meat is too thin to check the venting or increase the thickness of the meat. Heat pipe blocked, check circuit, temperature and repair. The mold is not cooling properly, confirm the water system and modify it.

Causes and countermeasures caused by raw materials: The raw materials themselves have poor fluidity, confirmation or material changes. Improper lubrication treatment, correct use of site and quantity. Overspray and reduce use.

In addition to insufficient filling, the following points also affect injection molding: plastic materials flow out from the joint surfaces of static and dynamic molds to form burrs, which are called burrs. Shrinkage: The list of molding parts often found in this phenomenon is mainly due to the raw materials in processing, which are thickened to the center of the meat, causing the surface of the finished product to sag. In particular, the surface of the meat is particularly large and the surface is more pronounced.

Flow path marking: After the molten material is injected into the cavity, the feeding point is taken as the center, and a ring pattern appears. Silver line: White line on the finished product with white as the flow direction. The surface has fog marks and gloss defects: the surface of some finished products is smooth and has a phenomenon similar to white clouds.

Connection line: a thin line injected into the mold, flowing through the runner, and then reconnected. Therefore, in order to manufacture qualified and flawless injection molding products, there are so many details to understand. This is what we need to cultivate high-quality technical personnel. In management, we must monitor and inspect each process repeatedly, especially the export of some foreign products So as not to cause unnecessary losses.

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