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Taizhou Union Plastic Mould Co.,Ltd

ADD:No.26, MaoFeng Street, Beicheng Development Area, Huangyan Dist., Taizhou, Zhejiang, China

Post Code: 312080

Contact:Ms vicky






Avoid Spraying Materials For Injection Molding Process And Mold The Requirements
Aug 03, 2018


      Requirements of non-spraying materials for injection molding process and mold: high gloss, high brightness, high-gloss steam mold injection parameters using high temperature and high pressure; High amount of mineral/metal powder is added, mould material is made of wear-resistant material. For the single gate mould, the proper position and shape of the glue inlet should be selected according to the size of the product. For multiple gate injection products, into the way to adopt order into the glue no spraying materials for product structure design requirements: little holes little rib avoid the complex structure of common coating resin, mainly include ABS PMMA/ABS, PC/ABS high-gloss ABS and so on, these material is suitable for used to do what needs to be better product surface gloss, but not all of the product structure can avoid spraying materials to do, because of, especially for surface has obvious hollow structure; On the back of the product, there are more screw column fasteners, reinforcing bars, etc. Products, such as uneven thickness of the middle part of the thin three typical prone to flow mark product structure of weld line, but not limited to the above three, complex product structures are prone to these problems and to improve these problems must be product structure mold molding technology materials cooperate to achieve four aspects at the same time, so avoid spraying material application in the actual product, need to accumulation of rich experience and system solutions to ensure the smooth progress of the project

1. The appearance surface of the product has obvious hole structure

To melt in the filling process, in the surrounding parts of the hole after shunt to meet again, and then create a weld line in the region of convergence problem, for normal dyeing material, weld line is only a fine line, for avoid spraying material, "visual" weld line on both sides of the color difference, so the weld line showed more obvious, therefore, apparent surface has obvious holes class product structure, generally avoid spraying material are not suitable for direct injection molding directly

2. On the back of the product, there are more screw columns, buckle, reinforcing bars and other product structures

Injection molding process, the filling to the screw post to the site, melt will produce shunt, partial melt longitudinal filling screw column/card buckle structure, part of the melt lateral filling product appearance, cause transverse flow amount is reduced, so in the region due to the change of flow state flow the flow mark problems 

3. The wall thickness of the product is uneven, and the middle part of the product is thin

Filling process, compared with the intermediate thinning, the flow speed is obviously faster than thinning on both sides of the area, both sides to middle coating formation, thus in the thinned parts combine the line at the end

Conclusion: although, avoid spraying has many benefits, but it does for the structure of products, its application is still relatively limited, the product defects is more prominent, however, to avoid spray product is widely used in: air-conditioning refrigerator panel LCD TV panel, decorative article speaker base panel small home appliance shell cosmetics packaging