Influences polyurethane spray hair There are many factors that determine the quality of foam. Next, we will mainly introduce the seven main factors that affect its quality. If you understand the following key factors, you can have a good control over the quality of your polyurethane spray foam.
1. The influence of the surface layer and surface layer of the wall base layer.
If there is dust, oil, moisture, and unevenness on the surface of the exterior wall, it will seriously affect the adhesion, thermal insulation and smoothness of the polyurethane foam to the insulation layer. Therefore, the wall surface must be clean and smooth before spraying.
2. The effect of humidity on aerosol foaming.
Since the foaming agent is easy to chemically react with water, the increased content of the product will easily increase the brittleness of the polyurethane foam, and in severe cases will affect the rigid polyurethane foam. Adhesion to wall surface. Therefore, the exterior wall of the building should be sprayed with rigid polyurethane foam before construction, and it is best to apply a layer of moisture-proof polyurethane primer(If the wall is completely dry in summer, you can save one step) .
3. The influence of wind.
Polyurethane foaming is done outdoors. When the wind speed exceeds5m/s, the heat loss during the foaming process will be too large, the loss of raw materials will be too large, the cost will increase, and the atomized droplets will easily fly with the wind. Environmental pollution can be solved with windproof curtains.
4. The influence of ambient temperature and wall temperature.
The suitable temperature range for spray polyurethane foam should be10°C-35°C, especially Wall surface temperature has a great influence on construction. When the temperature is lower than 10°C, the foam is easy to break off the wall and bulge, and the foam density increases significantly, which wastes raw materials; when the temperature is higher than 35°C, the foaming agent is lost too much, which will also affect the foaming effect.
5. Spraying thickness.
When spraying rigid polyurethane foam, the thickness of the spray also has a great impact on the quality and cost. When constructing polyurethane spray exterior wall insulation, due to the good thermal insulation of polyurethane foam, the thickness of the insulation layer is not large, generally 2.03.5 cm. At this time, the thickness of the spray should not exceed 1.0 cm. Make sure the surface of the spray insulation is smooth. The slope can be controlled within the range of 1.0-1.5cm. If the thickness of the aerosol is too large, the flatness will be difficult to control. If the thickness of the aerosol is too small, the density of the insulation layer will increase, wasting raw materials and increasing costs.
6. Spray distance and angle factors.
Generally, the working platform for hard foam spraying is scaffolding or hanging basket. To obtain good foam quality, it is also important to maintain a certain angle of the spray gun and spray distance. . Generally, the correct angle of the spray gun is controlled at70-90, and the distance between the spray gun and the object to be sprayed should be kept within 0.8-1.5m. Therefore, polyurethane spraying construction must be carried out by experienced professional construction personnel, otherwise the quality will be affected and the cost will be increased.
7. Interface treatment factors of rigid polyurethane foam insulation layer.
After spraying the rigid polyurethane foam to the required thickness, it can be carried out in about 0.5h Interface treatment, that is, brushing off the polyurethane interface agent. Generally, the application time of interface agent should not exceed 4 hours (it can be stored without sunlight). This is because after 0.5h of foaming, the strength of rigid polyurethane foam basically reaches more than 80% of the optimal strength, and the size changes…�� is less than 5%. Rigid polyurethane foam is already in a relatively stable state. and should be protected as soon as possible. The plastering of the leveling layer can be carried out after the polyurethane interface agent has been applied for 24 hours and finally solidified.
Be sure to pay attention to the impact of polyurethane during constructionpolyurethane Spray foaming quality factors to avoid unnecessary losses. It is recommended that customers choose a professional construction team to ensure both construction progress and project quality.