Problems that are prone to occur during the molding process include: blistering on the surface of the product and bulging inside; warping and deformation of the product; cracks in the product after being placed for a period of time; local fiber exposure of the product, etc. The causes of the relevant phenomena and the treatment measures are described as follows:
1. Bubbling on the surface of the product or bulging inside
The reasons for this phenomenon may be that the moisture and volatile content in the material is too high; the temperature is too high or too low; the pressure is insufficient, and the insulation time is too short; the material is heated unevenly, etc.
Solution: Strictly control the volatile content in the material and adjust the mold temperature appropriately. Reasonably control the molding pressure and insulation time. Improve the heating device to heat the material evenly.
2. Deformation and warping of the product
The reasons for this phenomenon may be that the FRP is not completely solidified, the molding temperature is low, the insulation time is insufficient, the thickness of the product is uneven, and the shrinkage rate is uneven.
Solution: Strictly control the curing temperature and insulation time. Choose a molding material with a small shrinkage rate. On the premise of meeting the use requirements of the product, appropriately change the structural form of the product to make the thickness of the product as uniform as possible or smooth transition.
3. Cracks
This phenomenon often occurs in products with inserts. The reasons may be: unreasonable structure of inserts in products; too many inserts; unreasonable demoulding method, too large difference in thickness of various parts of products, etc.
Solution: Change the structure of the product under the conditions allowed, and the inserts must meet the requirements of molding. Reasonable design of the demoulding mechanism to ensure uniform demoulding force.
4. Product underpressure, partial lack of glue
The reasons for this phenomenon may be insufficient pressure, excessive material fluidity, insufficient feed amount, or excessive temperature, so that part of the molded material solidifies prematurely.
Solution: Strictly control molding temperature, pressure, and pressurization time; ensure sufficient material, and no shortage of material.
5. Product sticking to the mold
Sometimes the product sticks to the mold and is not easy to demould, which seriously damages the appearance of the product. The reasons may be: missing the internal release agent in the material, the mold is not cleaned correctly, forgetting to apply the release agent, mold surface damage, etc.
Solution: Strictly control the quality of materials and operate carefully. Damaged molds must be repaired in time to achieve the required mold finish.
6. Product waste edge is too thick
The reason for this phenomenon may be unreasonable mold design; too much material is added, etc.
Solution: Make a reasonable mold design; strictly control the amount of material added.
7. Product size is unqualified
The reason for this phenomenon may be: material quality does not meet the requirements; material addition is not strict; mold wear; mold design size is not accurate, etc.
Solution: Strictly control material quality and accurately add material. The mold design size must be accurate. Damaged molds must not be used.
There are more problems with products during compression molding than the above. We can summarize experience, continuously improve, and improve the quality during the production process. Zhengxi provides high-quality composite material molding press machine. If you have any needs, contact us!
Post time: Apr-30-2025
