H.Foam Board Shrinkage and Deformation

H.Foam Board Shrinkage and Deformation

Shrinkage and deformation of foam boards are common quality issues in the production of XPS, EPS, and PET insulation foam boards. We offer corresponding solutions for different causes.

Possible Causes:

1. Insufficient foaming agent injection: Adjust the foaming agent injection amount according to the foam board parameters (based on experience, this is usually due to insufficient foaming agent injection, leading to bubble shrinkage and subsequent warping and deformation of the extruded board).

2. Excessive melt temperature: Adjust the melt temperature according to the raw material parameters (if the temperature is too high, the bubbles will burst and the gas will escape).

3. High melt flow index of raw materials, resulting in insufficient strength:

Replace with a masterbatch with a lower melt flow index (appropriately increase viscosity).

4. If the temperature of the left, right, or center of the mold is too high: Lower the overall mold temperature.

5. If  the foam board does not shrink in the middle but shrinks and deforms on both sides:

The temperature of the left and right sides of the mold is too high. Lower the temperature of both sides of the mold.