TPE injection molding manufacturers often encounter? During the sales process of TPE materials in 2017, friends often asked this question: TPE materials are mixed and modified materials, and the problems that occur in each material are different. This article lists some problems that everyone often encounters for reference.
Injection molding is also called injection molding. Injection molding methods have many advantages, fast production speed, high efficiency, automatic operation, simple and complex shapes, small sizes, and accurate product sizes, easy to replace products and complex shapes. Injection molding is suitable for mass production and other molding processing fields such as products with complex shapes.
The phenomenon of glue deficiency
not filling the end of the mold cavity is called glue deficiency . This is mainly caused by unsuitable molding conditions such as insufficient glue filling, but insufficient exhaust gas during molding or uneven flow path (multi-cavity mold) can also lead to this phenomenon.
Injection molding produces pores
collapsed holes in injection molded products, mainly caused by shrinkage during cooling of the molded products in the mold. In addition to requiring the material to be filled with the mold cavity, rapid cooling is also very necessary. Specifically, it is to increase the pressure holding (secondary pressure) and reduce the processing temperature of the thermoplastic elastomer material and the cooling temperature of the mold.
In addition, it also has a great dependence on the shape of injection molded products. Since pores are very likely to appear in thick parts, for such products, a glue injection port or a rubber flow channel should be provided around it.
Injection produces burrs (burrs)
This is caused by the overflow of the thermoplastic elastomer material from the cavity. For injection molding of rubber, it is normal to have burrs, but it is abnormal for resin or thermoplastic elastomers. The reasons are: (1) Compared with rubber materials, molten resin or thermoplastic elastomer has higher fluidity and lower injection pressure; (2) It can be cured and terminated in an instant when contacting and cooling with the mold. Therefore, resins and thermoplastic elastomers are usually not prone to burrs.
As a countermeasure, it is necessary to reduce the filling amount, reduce the holding pressure, and shorten the holding time. In addition, the mold needs to be repaired for dimensional accuracy and typing surface notches.
The phenomenon of silver stripes
The phenomenon of radial stripes appearing at the injection port is caused by the vaporization of moisture and volatile components in the material. Among them, it is involved during the plasticization process, and the residual air in the mold will cause this phenomenon. Therefore, the moisture-removing material must be fully dried before forming to reduce the molding temperature of the decomposed gas material.
TPE injection molding manufacturers have many problems encountered during the production process, and some problems are indeed difficult to deal with. TPE products need to be done well to cooperate with raw materials, molds, and injection molding manufacturers. If you have any problems in the injection molding process, we, as a TPE raw material supplier, will definitely cooperate with you and provide corresponding technical support.
