The shrinkage in the blocking direction is always less than that in the unblocked direction, and the shrinkage near the insert is less than that far away from the insert. The shrinkage of products with complex shape is smaller than that of products with simple shape. There is also a significant difference between the flow direction and the contraction perpendicular to the flow direction. Generally speaking, the contraction in the flow direction is greater than that in the flow direction. The following is a detailed description of the factors affecting the shrinkage of Jinan self sealing bags.

　　其次要說的是提高自封袋模具的溫度，一般會增加收縮率，特別是對于結晶塑料。延長保溫時間可降低收縮率。但一旦澆口關閉，延長保溫時間將不再影響收縮率。

　　The second thing to say is to increase the temperature of the self sealing bag mold, which will generally increase the shrinkage, especially for crystalline plastics. The shrinkage can be reduced by prolonging the holding time. However, once the gate is closed, extending the holding time will no longer affect the shrinkage.

　　還有一點是，增大壓力會導致塑料拉鏈袋密度增大，從而使收縮率降低。提高材料的溫度會使產品的體積膨脹，減少進入腔體的材料。然而，材料溫度的升高會降低粘度，但有利于壓力向空腔的傳遞，降低收縮率，收縮率取決于上述兩種效應的綜合影響。一般塑料的粘度是對溫度變化敏感的，是后者。

　　Another point is that increasing the pressure will increase the density of the plastic zipper bag, thus reducing the shrinkage. Increasing the temperature of the material will expand the volume of the product and reduce the material entering the cavity. However, the increase of the material temperature will reduce the viscosity, but it is conducive to the transfer of pressure to the cavity and reduce the shrinkage, which depends on the combined effect of the above two effects. The viscosity of general plastics is sensitive to temperature change, which is the latter.

　　以上是濟南自封袋廠家小編為大家介紹的相關內容，想要了解更多內容，歡迎訪問網站：http://www.ksdgwy.com

　　The above is the relevant content introduced by Jinan self sealing bag manufacturer. If you want to know more, please visit the website: http://www.ksdgwy.com