Injection molding is a process involving many factors mold design, mold manufacturing, material properties and a pretreatment method of raw materials, molding, injection molding machine operation, and processing and environmental conditions, the article cooling time, post-treatment process is closely related to the complex Manufacturing processes. Accordingly, no single product quality is good or bad depends on the accuracy of the injection molding machine, metering accuracy, or determined level of accuracy and merits of the mold only by the mold design, normally, it is also influenced by other factors described above, and constraints.
　　In so many complex factor constraints, occurrence of a defect on the injection molded article is inevitable, then, to find an inner product defects and a prediction mechanism may be the type and location of defects, and used to guide and improve the mold design, induction defect law created to develop a more rational process operating conditions is particularly important. Our three main factors plastic material properties in the injection molding process, the mold structure, injection molding and injection device from the injection molding defects to illustrate the impact generating mechanism and solutions.
　　Common defect classification injection molded article
　　injection molding process used in a variety of plastic raw materials, mold design and type of form is varied, Additionally, operation of the operation for a particular skill among workers of injection molding machines and workers familiarity, practical experience differences also vary, while the objective environment (e.g., ambient temperature, humidity, air cleanliness) will vary depending on the season, which together determine the objective and subjective conditions of the injection molding to produce product defects.
　　In general, the performance of the article for the evaluation of the merits of plastic there are three main aspects:
　　First, the quality of appearance, including integrity, color, luster;
　　second, the accuracy of the sizes and relative positions between, i.e., dimensional accuracy and position accuracy;
　　third, with the appropriate mechanical properties, chemical properties, electrical properties and other purposes, i.e., functional
　　thus, if a link for any of the three aspects of the problem, will lead to the generation and propagation of defects article.
　　Common defect classification injection molded article
　　appearance defects: silver streaks color, weld line
　　Process problems: flash, shrinkage, lack of adhesive
　　performance problems: warping, embrittlement