An Experimental Study on The Removal of Weldline by Moving Core Method

이동식 코어를 적용한 웰드라인 제거에 관한 실험적 연구

Yun, Gyeong-Hwan;Jo, Gwang-Hwan

  • Published : 2000.07.01


Injection molding is one of the most popular processes in plastic industry. Despite the significant progresses in technical point of view there are still problems to be solved in injection molding process. One of these problems is well-known weldline. A weldline is formed when the two flow front seperates and rejoins during the filling process. The flow front separation is caused by an obstruction in the cavity such as core, inserts and multiple gates. The typical occurrence of weldlines is one of the most undesirable phenomena in injection molding because the molded product's appearance is damaged and its strength is reduced considerably. A major factor which weakens the strength is the V-notch structure in its surface and parallel molecular orientation in inner structure. Several methods were tried to remove the weldline in injection-molded parts, but in fail. In the present paper a new technique to remove the weldline is proposed. This technique is named as ,'moving core method


Moving Core;Weldline;Frozen Layer


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