Causes and solutions of dents in plastic products  

1.  Causes of dents   

1 , the thickness of each part of the product is different    

2. Insufficient pressure inside the mold   

3.  Insufficient mold cooling    

4.  Deformation due to insufficient cooling time 

2. Related knowledge

1.  During the production process, dents are the most frequent occurrence of undesirable phenomena. The plastic injected into the mold shrinks in volume when it is cooled. The early cooling part means the surface hardens first, and bubbles will be generated inside. The so-called dent is cooling. The slow part creates a conspicuous concave surface in the direction of bubble contraction. Plastic Products Factory

2.  Materials with large shrinkage are also prone to dents. When changing the molding conditions to eliminate dents, the setting conditions should be set in the direction where the shrinkage is small. That is, the mold temperature and barrel temperature decrease, and the injection pressure increases, but it should be noted that this may cause residual internal stress.

3.  Because the dents are better to be inconspicuous, if they do not affect the appearance, they are deliberately processed into a corroded pattern on the mold, such as grains, grains, etc. Tianhe Plastic Products Factory

Guangzhou Plastic Products Factory

Three, the solution

1.  Instant: Increase injection pressure, extend injection holding time, reduce barrel temperature and mold temperature, and force cooling where dents occur. Guangzhou Plastic Products Factory

2.  Short-term: fill up the flow edge where the dent is generated. When the material in the place where the dent is generated has a narrow place through the edge, make this part thick.

3. Long-term: The difference in thickness of the designed product should be completely avoided. For ribs that are prone to dents, the long and narrow shape should be as short as possible.

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