No matter what is in different seasons, we need to pay attention to different things, and the same is true for PU foam. The precautions are different in different seasons, and the use methods are slightly different. So you know what should be paid attention to when using PU foam in low temperature and dry seasons? How to use it?
What should I pay attention to when using PU foam in low temperature and dry seasons?
1. One component, moisture curing polyurethane foam sealant, commonly known as foam adhesive, is cured by chemical reaction with moisture in the air. If there is less water in the air and the ambient temperature of reaction is low, the curing time and the performance of cured foam will be greatly affected.
2. In late autumn, winter and early spring, due to the impact of cold air in most parts of China, the air is dry and the temperature is low, and the construction environment is poor, which brings great difficulties to the use of foam adhesive. According to previous years' experience, if the operation is not carried out in accordance with the specifications during construction, it will cause slow curing of the foam adhesive, cavities, poor bonding and other phenomena, which will affect the construction quality.
How to use the PU foam in the low temperature and dry season?
1. The normal operating temperature of the foam adhesive is ＋ 5 ～ ＋ 35 ℃. For construction at low temperature, it is recommended to place the product in 25~30 ℃ warm water for about 5 minutes before use to increase the tank temperature to ensure its * * * performance. However, do not overheat or directly contact with open flame.
2. The floating ash and oil stain on the construction surface will affect the bonding effect of the foam adhesive. Therefore, the construction surface should be properly cleaned before construction to ensure the bonding effect of * * *.
3. Foam adhesive is a wet curing product. Spray a little water on the construction surface before construction to improve the environmental humidity, which can significantly shorten the curing time and improve the overall quality of foam.
4. When installing wooden doors with foamed plastic, they must be properly fixed and supported before and after installing door jambs and door leaves to avoid deformation. After the gap between the door jamb and the wall is filled with PU foam, there shall be no external force within 24 hours, otherwise the wooden door may be displaced, loosened or even fall off later.