Application of the hottest barrier anticorrosive c

The application of barrier anticorrosive coating in the anticorrosion of tap water pipeline

1 main performance characteristics

barrier anticorrosive coating is an epoxy acrylic polyurethane coating. The prepolymer containing isocyanate is mainly prepared from organic polyhydroxyacrylate homopolymer and polyisocyanate, and then it is mixed with its dispersion by ionic or non-ionic dispersion through polyamine extended polyurethane. At the same time, it is added with special stabilizer, antioxidant, accelerator, anti-corrosion additive and color filler to prepare a long-term high-performance non-toxic anti-corrosion coating, This kind of modified polyurethane coating has special properties different from any other traditional coatings

1.1 significant oxygen resistance and chemical corrosion resistance

as we all know, the infiltration of water and oxygen is the root cause of metal corrosion. From the perspective of electrochemical reaction, active rust is the main cause of corrosion. Therefore, the close molecular structure of the film is directly related to the shielding effect of the film, and the resistance of the film itself to corrosive media is the key to the quality of the coating. The barrier anti-corrosion coating is not only better than any other traditional coating in terms of moisture passing rate, but also can withstand all kinds of corrosion caused by salt water, dry wet cycle in coastal high-temperature and high humidity areas, various gas-phase corrosion media in industrial developed areas and the alternating action of saline alkali medium and acid-base medium in marine atmospheric environment. After 1440h room temperature destructive test in different proportions of solutions with different corrosive media, it is shown that even if the metal template is corroded, the anti-corrosion coating is still intact, and some physical and chemical properties are not changed

1.2 excellent adhesion, toughness, high hardness and wear resistance

relevant experts pointed out that the dynamic mechanical properties of paint film mainly refer to the impact strength of materials, and the impact strength is closely related to its tensile strength and elongation at break. After measurement, the barrier coating has excellent impact resistance and ductility, which can be traced back to the ancient age. It is a coating with high film capacity, friction resistance, high hardness and strong adhesion, and can be used in a certain temperature environment (100 ℃)

1.3 good weather resistance

light aging will often cause the surface and physical properties of the coating to deteriorate. The most common phenomena are loss of light, yellowing, cracking and chalking, and even embrittlement and peeling. According to the photodegradation mechanism, the free radicals in the resin are important intermediates causing photodegradation. Therefore, an important means to promote light stabilization is to remove the free radicals in the resin, and the hydroxylamine ether in the barrier coating modified resin can effectively remove the free

radicals and inhibit light oxidation

at the same time, it can effectively prevent the killing of ultraviolet rays and stabilize the color retention of the coating through the role of anti-oxygen groups, which is more than three times longer than the service life of general anti-corrosion coatings

2 application of pipeline corrosion prevention

2.1 derusting process

derusting process is simpler than other anti-corrosion coatings. It only needs to remove the floating rust, welding slag, oil stain and loose matter on the surface of the coated workpiece with sandpaper, wire brush or electric grinder, and wipe it up to be flat and dry. It should be emphasized that the floating rust, oil and other debris on the surface of the coated workpiece must be removed, because floating rust, oil and other debris may form an isolation layer on the surface of the workpiece, which will directly affect the adhesion and coating quality of the coating. 2.2 coating process

the product is a two-component coating, which can be applied by brushing, spraying, roller coating and other methods

① anti corrosion coating structure:

a. ordinary anti-corrosion type (two bottoms and two sides) one primer, one primer, one finish paint and one finish paint. The dry film thickness is about 100um

b. one coat of primer, one coat of glass fiber cloth and two coats of finish paint for the reinforced anti-corrosion type (one cloth and three oils). The dry film thickness is about 200umc. heavy reinforced anti-corrosion type (two cloth and four oil), one primer, one primer, one primer, one finishing coat. The dry film thickness is about 300um. Or one primer, continuous winding of two layers of fiberglass cloth, one primer and two finishing coats. The dry film thickness is about 300um

D. specially strengthened anti-corrosion type (three cloth and five oil), one layer of primer and two layers of fiberglass cloth wound continuously. One primer, one layer of fiberglass cloth, one primer and two finishing coats. The dry film thickness is about 450um. Or one layer of primer, one layer of fiberglass cloth, one layer of primer, one layer of primer, one layer of fiberglass cloth and two layers of finish paint. The dry film thickness is about 450um

② coating preparation: according to the dosage, prepare as you use, mix in proportion, mix well, and wait for 10-15 minutes before applying

coating

③ the construction industry also began to face the viscosity of energy output from different channels: the construction viscosity can be adjusted with special diluents. The application viscosity is 30-40s

④ drying conditions: natural drying at room temperature. ⑤ Precautions:

a. avoid mixing water, oil and other substances in the preparation and construction process, so as not to affect the project quality

b. when applying primer and finish paint, the coating shall be uniform without omission

c. when winding the glass fiber cloth, it must be tight, flat, free of wrinkles and bubbles, and the fiber cloth eye must be filled with paint. The lap width between glass fiber cloth is more than 20 mm, and the lap length is more than 100 mm. When winding two layers of glass fiber cloth, the lap joints of each layer of glass fiber cloth shall be staggered. The anti-corrosion coating at both ends of the pipeline shall be made into a stepped joint, and the step width shall be more than 100 mm. The warp and weft density of glass fiber cloth is 10 × 10 pieces/cm2 or 12 × 12 pieces/cm2, the thickness should be (0.12 0.01) mm, the alkali content should not exceed 12%, twistless, wax free, plain, edge sealing on both sides, and the wet fiberglass cloth must be dried before use

d. pay attention to avoid damaging the anti-corrosion coating of the pipeline or steel parts after painting during transportation and hoisting. If there is any damage, it should be repaired in time, otherwise it is not allowed to install

e. when the interface anti-corrosion brush is applied in the pipe trench, the soil and water traces at the anti-corrosion part must be removed. The backfill should not damage the vision and smell of the external defense. In fact, this forward-looking statement cannot guarantee the tactile decay layer of future deeds

f. outdoor construction is not suitable in rainy, snowy and foggy days

g. transport as dangerous goods to prevent exposure to rain and sunlight

h. keep close to the fire source and store it in a cool and dry place

i. ventilation and open fire are prohibited during construction

3 conclusion

① barrier series coatings are high-tech products in today's paint market, and their performance indicators meet and exceed the traditional anti-corrosion coatings

② barrier coating is a non-toxic protective coating against acid, alkali, salt, oil, water and atmospheric corrosion, which is suitable for the corrosion prevention and protection of various metal, wood and concrete components

③ barrier coating has the advantages of simple construction, fast drying, wear resistance and good adhesion. It is especially suitable for the anti-corrosion engineering of water and oil pipelines, as well as the anti-corrosion engineering of salt making, chemical industry, industrial floors and floors

④ the service life of barrier coating is more than three times that of general anti-corrosion coating, and the comprehensive cost is significantly lower than that of traditional anti-corrosion coating. It is an ideal anti-corrosion coating today. (end)