Generally speaking, there will be serious deformation of pulp molding products because of different causes, so we should do something to prevent the deformation. If we want to stop this deformation, we first should know how this deformation happened, then according to the cause to adopt different solutions.
Causes of serious deformation of pulp molded products
- Due to the improper design of the mold, the local thickness of the paper molded product is too large, resulting in uneven drying and deformation of the paper molded product.
- Paper mold products are dried too quickly or heated unevenly. The paper mold products often deformation in the mold design reasonable conditions, which is due to drying too quickly or a part surface heating temperature higher than other parts.
Solutions for solving deformation of pulp molding products
- Under the condition of not affecting the packaging function of paper molded products, the design of the mold is improved to eliminate the phenomenon of excessive thickness of the paper film locally, and some anti-deformation structures can be added to improve this situation.
- In the initial stage of drying, the temperature is relatively high, and the temperature should decrease slowly when it is close to the midpoint. If conditions permit, a longer drying tunnel can be configured to reduce the drying temperature and prolong the drying time as much as possible to make the paper molded product as a whole uniform.
- In order to reduce the deformation of paper moldings, more mechanical pulp can be used, because its shrinkage rate is smaller than other sticky chemical pulps, and at the same time, it can reduce the burr phenomenon of paper moldings