Cracking of polyurethane foam during foaming can be caused by a variety of factors, including improper mixing, insufficient curing, or incorrect foam chemistry. Here are some steps you can take to solve this problem:
1.Check the foam chemistry: Make sure that the foam chemistry is appropriate for the application and that the foam is being produced within the recommended temperature and pressure range. Improper chemistry or temperature can cause the foam to become brittle and crack.
2.Adjust the mixing: Ensure that the foam chemicals are being mixed properly and at the correct ratio. Improper mixing can cause areas of the foam to become denser or lighter than others, leading to cracking.
3.Increase curing time: If the foam is not given enough time to cure, it may not set properly and can crack. Increasing the curing time can help to prevent cracking.
4.Adjust the mold temperature: If the mold temperature is too low, it can cause the foam to set too quickly, leading to cracking. Increasing the mold temperature can help to prevent this.
5.Use a different foam formulation: If the above steps do not solve the problem, you may need to try a different foam formulation that is more suitable for the application.
It’s important to note that cracking in polyurethane foam can also be caused by external factors, such as handling or transportation. Proper handling and packaging can help to prevent cracking after the foam has been produced.