Pay attention to the following seven points during the construction of the Best POLYURETHANE SEALANT FOR GENERAL USE china.

1. Treatment of the sealed surface: before construction, clean up the garbage and sundries left after the previous construction, and then use a blower or vacuum cleaner to clean up the floating ash. If the base surface is wet, dry it with a blowtorch and brush it with a steel wire brush to remove the cement chips and dust falling after baking. Remove the greasy dirt, plastic attachments, dust and other sundries on the adhered surface (the Best POLYURETHANE SEALANT FOR GENERAL USE china does not stick to plastic and greasy dirt, and can be operated with portable cutting machine, grinding wheel, steel brush and other tools). Blow the sundries with a blower to expose the solid structural layer on the glued surface. The joint surface must be completely dry, clean and frost free. All dust and cement slurry on the surface must be cleaned. The surface to be adhered must be absolutely dry and flat to prevent poor adhesion. The rust layer and protective paint on the metal surface also need to be removed. If the structure is not dry, it can be dried with blowtorch.

2. Before the construction of the Best POLYURETHANE SEALANT FOR GENERAL USE china, 50mm wide protective tape shall be pasted at 10mm on both sides of the gap to prevent the excess polyurethane sealant from fouling the surface of the structure during the construction.

3. Apply primer before the construction of the Best POLYURETHANE SEALANT FOR GENERAL USE china: for projects where the design requires the use of primer, or for the sealing of long-term flooded parts, the primer shall be applied to the surface to be adhered and dried to form a film (primer is equipped separately).

4. Preparation of the Best POLYURETHANE SEALANT FOR GENERAL USE china: mix a barrel of white one component the Best POLYURETHANE SEALANT FOR GENERAL USE china (component a) with a bag of black curing agent (component B) until there is no color difference. The specific methods are as follows: pour two groups of one component polyurethane sealant A and B onto a glass plate or floor tile at the same time (the floor tile requires 60 cm square is the best). According to the mix proportion given in the manual, the mix proportion a:b=100:10 ~ 100:14 (mass ratio), mix the two components evenly, and then use it. When leaving the factory, our company has been proportioned according to the mass proportion, and opened it with a plastic cylinder. Users do not need to worry about the mass proportion, When using, just open the package, put component A and component B together, and mix them evenly. The manual mixing time is not less than 9 minutes, and the portable electric drill mixing time is not less than 6 minutes. It is appropriate to use the mechanical mixing method, and the mixing time should be long rather than short, so as not to achieve the waterproof sealing effect due to incomplete partial curing caused by uneven mixing. Whether mixed by machine or by hand, the color should be uniform without color difference. When mixing, bubbles should be prevented from mixing, and the prepared one component polyurethane sealant should be used up within 2 hours, otherwise it will slowly thicken, causing construction difficulties and reducing performance. Therefore, pay attention to how much you use, otherwise it will cause waste due to too much.

5. When applying one component the Best POLYURETHANE SEALANT FOR GENERAL USE china, first apply a layer of the prepared sealant on both sides of the joint with a gray knife, and then embed the Best POLYURETHANE SEALANT FOR GENERAL USE china in the middle of the seam to the specified thickness. For narrow joints and special parts that are difficult to be constructed with a gray knife, the mixed one component polyurethane sealant can be loaded into the construction glue gun and then driven into the construction part. During operation, try to prevent entrained bubbles from entering the butyl sealant. For the parts of materials that are not easy to be bonded, the bonding effect should be guaranteed. It is best to use a special primer first and then apply the dense adhesive (the primer is equipped separately). Prevent bubbles from mixing. Remember to compact and fill the sealing place to prevent bubbles from mixing when applying glue. The stirred one component polyurethane sealant must be used up within 2 hours, because the paste colloid begins to solidify slowly under the action of chemical components after 2 hours. (the surface drying time is ≤ 24 hours, and the irrigation test can be carried out after 7 days, and the performance is all achieved in 28 days.)

6. After the construction of the Best POLYURETHANE SEALANT FOR GENERAL USE china is completed, the protective tape on both sides of the gap can be removed, and the water shall be prevented from washing and raining within 24 hours.

7. Inspection of construction quality: after the construction of the Best POLYURETHANE SEALANT FOR GENERAL USE china is completed, the joints shall be comprehensively inspected, and the joints shall be repaired in time in case of missing scraping, unevenness, sagging, etc. The surface drying time of the Best POLYURETHANE SEALANT FOR GENERAL USE china is 24 hours, but it can reach 80% strength after 7 days. Therefore, before the one component polyurethane sealant is fully cured, attention should be paid to protection to prevent rainwater intrusion and reduce its performance. The closed water test must be carried out after 7 days of construction. Good adhesion; Good elasticity, excellent restorability, suitable for dynamic joints; Good weather resistance, with a service life of 15-20 years; Excellent oil resistance; Resistance to biological aging; The price is moderate. Polyurethane sealant also has some disadvantages. For example, it cannot be heat-resistant for a long time; Light color formula is easy to be aged by ultraviolet light; The storage stability of one component adhesive is greatly affected by packaging and the outside world, and it usually solidifies slowly; Bubbles and cracks may occur under high temperature and thermal environment; Primer is required for many occasions. At the same time, the water resistance of polyurethane sealant is also poor, especially the alkali water resistance.