Common Injection Molding Defects & Practical Solutions
(常见注塑成型缺陷及实用解决方案)
In the process of custom plastic injection molding, various defects may appear on finished products due to mold structure, raw material performance or improper parameter setting. These issues will affect product appearance, dimensional accuracy and service life. As a supplier focusing on custom plastic mold development and one stop plastic customization, we summarize the most frequent defects and effective solutions for global customers, to help you better control product quality during mass production.
(在定制塑料注塑成型过程中,受模具结构,原料性能,工艺参数设置等因素影响,成品容易出现各类瑕疵,直接影响外观,尺寸精度与使用寿命.作为专注定制塑料模具开发与一站式塑料定制服务的生产厂商,我们整理了行业高发缺陷及对应解决方案,助力客户在量产阶段把控产品品质.
1. Shrinkage Marks (产品缩水凹陷)
Shrinkage is one of the most common defects in plastic products. It usually occurs on thick-walled areas, rib positions or boss surfaces.
(缩水是塑料制品最常见的缺陷之一,多出现于产品厚壁处,加强筋或柱位表面.)
Main Causes (主要原因):
Insufficient plastic material filling and packing pressure
Unreasonable mold cooling system design
Excessive wall thickness difference of the product
( 主要原因:熔胶填充不足,保压压力不够,模具冷却系统设计不合理,产品壁厚差异过大)
Solutions( 解决办法)
Increase packing pressure and extend pressure holding time
Optimize cooling channels to ensure uniform heat dissipation
Adjust product structure properly during DFM analysis to reduce wall thickness gap
解决办法:(加大保压压力,延长保压时间 ,优化模具冷却水路,保证散热均匀,在前期可制造性分析阶段优化产品结构,缩小壁厚差)
2. Product Warpage & Deformation( 产品翘曲变形)
Warpage refers to bending or twisting of plastic parts after demolding, which leads to unqualified assembly size. It happens easily on thin and large-size plastic components.
(翘曲变形指产品脱模后出现弯曲,扭曲现象,造成装配尺寸不合格,大尺寸,薄壁塑件尤为多发.)
Main Causes( 主要原因)：
Uneven cooling speed inside the mold
Unbalanced ejection force
Different shrinkage rates of plastic materials in different directions
(主要原因 • 模具内外冷却速度不均 • 顶出受力不平衡 • 原料各方向收缩率存在差异)
Solutions( 解决办法)：
Reconstruct cooling system to balance temperature of mold cavity and core
Optimize ejector pin layout to make force evenly distributed
Adjust injection speed and temperature according to material characteristics
(解决办法：重新规划冷却水路,平衡型腔与模芯温度,优化顶针排布,保证顶出受力均匀,根据原料特性调整注塑速度与料温)
3. Air Bubbles & Voids (气泡与空穴)
Air bubbles inside or on the surface of plastic parts will seriously reduce product strength, which is a fatal defect for industrial plastic accessories.
(产品内部或表面出现气泡,会大幅降低结构强度,对于工业塑胶配件而言属于严重不良问题.)
Main Causes (主要原因)
Moisture contained in raw plastic materials
Too fast injection speed leading to air trapping
Unreasonable exhaust slot design of the mold
(主要原因：塑料原料含有水分,注塑速度过快,型腔困气,模具排气槽设计不足)
Solutions 解决办法
Dry plastic raw materials before production
Slow down injection speed and optimize material feeding path
Add exhaust slots at product edges and deep cavity positions
(解决办法:生产前对原料进行烘干处理,降低注塑速度,优化进胶路线,在产品边缘,深腔位置增设排气槽)
4. Flash (Burrs) 飞边毛刺
Flash means extra thin plastic edges around the parting line, pin holes and insert positions. It affects assembly and appearance.
(飞边是指产品分型面,孔位,嵌件位置出现多余塑胶毛边,影响装配与外观效果.)
Main Causes (主要原因):
Loose mold clamping or worn mold parting surface
Excessively high injection pressure and material temperature
Overloading of mold structure
(主要原因:模具锁模力不足或分型面磨损,注塑压力,料温过高,模具结构承压过大)
Solutions 解决办法
Repair worn mold surfaces and increase clamping force
Appropriately lower injection pressure and barrel temperature
Optimize mold structure to avoid local overpressure
(解决办法:修复磨损模具面,加大锁模力,适当降低注塑压力与料筒温度,优化模具结构,避免局部受力过载)
Summary 总结:
High-quality custom plastic injection molding relies on mature mold technology and precise production control. All the above defects can be effectively avoided through early DFM optimization, reasonable custom plastic mold development and standardized production operation.
(高品质的定制塑料注塑成型,依托成熟的模具工艺与精细化生产管控.通过前期可制造性优化,合理的定制塑料模具开发以及标准化作业,以上各类缺陷均可有效规避.)
Xingtai Huarui Rubber & Plastic Products Co., Ltd. provides full-set one stop plastic customization services from design, mold making to mass production. We strictly control every production link to deliver stable and high-quality plastic products for global clients. Welcome to send us drawings or samples for inquiry.
(邢台华锐橡塑制品有限公司提供从设计,模具制造到量产的全套一站式塑料定制服务,严格把控每一道生产环节,为全球客户交付稳定优质的塑胶产品.欢迎各界客户来图,来样咨询合作.)
