Why the PVC foam profile appear the gap ?

Xinda Plastic Machinery Co., Ltd. Supply the PVC imitation marble profile production line machine, production process and adjust the recipe to produce PVC foam marble profile or solid marble profile , PVC foam profile more lighter , and the cost lower, but in use, they always appear gaps problem, the specific reasons for analysis:

Foaming appearance of the lines is to determine one aspect of its quality, and therefore manufacturers of employees in the manufacturing process will be observed surface of the molded foam lines, I hope there is no defect, but sometimes that I’m sorry things, produced by foaming lines present on the surface cracks, some relatively long and narrow, and some relatively small. Why line the surface will appear a gap?

1, the ratio of manufacturing lines with foamed material unreasonable. Material ratio unreasonable, the material in the molding process thermal expansion of the internal situation is not the same, leading to stress in some places is relatively large, so that the cooling process occurs later in hairline cracks, small cracks gradually widen the gap became a.

2, stirring the foam material is not stir. Stir it will lead to no material density of the molded lines in different parts of the material difference between the larger, so that the cooling process there will be a large difference between the stress change, big change places prone to cracks.

3, the foaming process of the foam box to set the ambient temperature is relatively high, which causes premature aging of the material during the foaming process, its softness, ductility are reduced in the latter line molding process prone to open a gap.