Mentioned waterproof coating construction, a lot of people will think, this is wipe besmear daub, shouldn't be hard, but if you want to complete this procedure, ensure that later don't leak, is to have cultured, take a look at. Waterproof coating construction of six major difficult and complicated
1. The waterproof coating is not well bonded to the base
The specific phenomenon
Paint and base adhesion or foaming or not enough adhesion.
Prevention and control measures
The grass roots must be cleaned; The strength of the base shall not be sanded, peeled or loosened. Water-soluble coatings shall not contain bright water; The solvent - based coating base must be dry. A primer must be used for the first coat.
2. Waterproof coating cracks
The base is not clean and there is floating ash on the base. The deformation of the base layer is large, and the cracking of the base layer leads to the cracking of the coating film. Water-borne coating cracking is mainly caused by the low humidity of the base layer compared to the dry environment, and the rapid water loss during the evaporation process of coating film, resulting in cracking. Excessive thickness of the coating at one time leads to uneven moisture volatilization and cracking of the coating during the drying process.
Clean the base layer to ensure that there is no floating dust and floating slurry on the base surface; When applying water-based paint, wet the base first, and then apply the film multiple times.
3. Waterproofing coating into bean dregs
Excessive hydration leads to separation of liquid and powder, or uneven mixing, which leads to the separation of liquid and powder in the coating and the subsidence of powder, like bean curd residue. Improper storage of paint, exposure to the outside and exposure to cold can cause such phenomenon; Fake goods also appear bean curd residue phenomenon.
Strictly control the amount of water added. Control the amount of water used for one day, so as not to leave the water products overnight. Store as required.
4. Waterproof coating is transparent
The film coating thickness and brush number are not enough, there is the phenomenon of cutting corners.
Strictly control the number of brush strokes. The 1.5mm thick film should be applied at least three times.
5. Yellow spots and embroidery spots appear in the waterproof coating at the root of the tube
The root of the pipe is cast iron pipe. When the pipe is coated with waterproof coating, no derusting treatment is carried out. As a result, the cast iron pipe will rust through the coating, causing rust spots, yellow spots and other phenomena.
For metal parts such as cast iron pipe, when coating film, first use sandpaper or wire brush to polish and remove rust, and then film coating brush.
6. Waterproof coating dry slowly
Because a single component acrylic coating is made by evaporation of water into a film, high humidity, low temperature environment, which hinders the evaporation of water in the paint, so the drying speed is relatively slow.
Prevention and control measures
Enhancing indoor ventilation conditions can be more conducive to the development of water; Adopt thin coating and multilateral coating, more conducive to the evaporation of water, in the construction of the film must wait until each coating dry before painting; Use cement - based coatings for construction or other waterproof coatings.