Test you: What are the tips and control points when applying primer?

This post was last edited by mopeizhi on 2010-2-7 15:57. The reference answer provided by this site is: Primer is the coating under the intermediate or top coat in the coating system, or the coating applied directly to the surface of the substrate. The primer must have good protective properties for the base material, and have good adhesion and mechanical strength. It serves as an intermediary layer between the surface to be painted and other coatings, so that the two are firmly combined to form a solid covering layer. The primer must have high anti-rust ability and the ability to fill the surface. Anti-rust pigments are usually added; because the primer is generally not directly exposed to the atmosphere, the weather resistance performance is not high. Various types of resins have corresponding primers. The most commonly used ones are: epoxy primer, asphalt primer, alkyd primer, phenolic primer, chlorinated rubber primer, vinyl primer, polyurethane primer, epoxy asphalt primer, etc. Different types of coatings are used depending on the coating requirements and usage months. The most commonly used methods for applying primer are brushing and spraying. Brushing primer is especially suitable for construction on corners and other complex-shaped parts to increase coating adhesion; high-pressure airless spraying can apply a higher film thickness of anti-corrosion coating at one time and is suitable for large-area construction. The key points for applying primer are as follows. ①The general principle of selecting an appropriate primer based on the material of the object to be coated is: wood products, leather, paper, textiles and thermoplastics cannot choose coatings that are baked into films at high temperatures and must use self-drying coatings; light metals such as aluminum and magnesium and their alloys are not allowed to use coatings containing iron red and red lead anti-rust pigments; cement surfaces need to use primers with good alkali resistance; the flexibility of the primer used for plastic leather needs to meet the requirements. ②Choose the appropriate primer type according to different usage environments and usage days. ③The primer contains a high content of pigments and fillers and is prone to precipitation, so it should be stirred thoroughly before use to ensure a consistent pigment-base ratio; it should also be stirred regularly during use. ④The pretreatment of the base material should be strictly in accordance with relevant standards. For example, the steel surface should be degreased and rust-free and reach Sa2 level or above. ⑤The primer should be applied evenly and completely without any leakage or sagging. Generally, the film thickness of the anti-rust primer is controlled at 150-250 μm. The coating should be applied in a criss-cross manner and at least two coats (one-time film-forming paint can be excluded, but two coats should be applied if conditions permit) to avoid missed coatings. ⑥The amount of primer diluent added cannot exceed 5% of the total L, and the corresponding installation operation points and procedures should be strictly followed. ⑦The next coat should be applied in accordance with the drying time and optimal coating interval specified in the technical conditions. For topcoats containing strong solvents, the primer must be completely dry. In order to save energy and improve the adhesion of the coating film, the "wet-on-wet" construction process can be used, that is, spraying a thin layer and then drying it only to allow the solvent in the coating to volatilize to a certain extent. When the coating is still wet, spray a second coat and then dry it once. The "wet-on-wet" construction method is limited to certain coatings, such as amino, perchlorethylene, polyurethane, and epoxy coatings. ⑧When selecting the middle layer and topcoat, strictly follow the material matching principles to avoid the phenomenon of "bottom biting". For example, polyurethane topcoat cannot be applied to alkyd primer, only oily and alkyd varnishes, enamels, etc. can be applied. In harsh and special anti-corrosion environments, epoxy, epoxy asphalt, and polyurethane two-component paints are generally used as primers. The topcoats can be high-end polyurethane, fluororesin, chlorinated rubber paints, or alkyd and other enamels.

This post was last edited by mopeizhi on 2010-2-7 15:58 Primer is the coating under the middle layer or top layer in the coating system, or the coating directly applied to the surface of the substrate. The primer must have good protective properties for the substrate, and have good adhesion and mechanical strength. It serves as an intermediary layer between the surface to be painted and other coatings, so that the two can be firmly combined to form a solid covering layer. The primer must have a high ability to prevent rust and fill the surface of the material. Anti-rust pigments are generally added. Since primers are generally not directly exposed to the atmosphere, their weather resistance requirements are not high. Various resin varieties have corresponding primers, the most commonly used ones are: Epoxy primer, asphalt primer, alkyd primer, phenolic primer, chlorinated rubber primer, vinyl primer, polyurethane primer, epoxy asphalt primer, etc. Different types of coatings are used according to the coating requirements and purpose of use. The method of applying primer may be selected according to the construction methods in Chapter 3, but the most commonly used methods are brushing and spraying. Brushing primer is especially suitable for construction on corners and other complex-shaped parts to increase coating adhesion. ； High-pressure airless spraying can apply a relatively thick anti-corrosion coating at one time and is suitable for large-area construction. The following points should be noted when applying primer. (1) Select an appropriate primer according to the material of the object to be coated. The general principle is: Wood products, leather shoes, paper, textiles and thermoplastics cannot use high-temperature baking film-forming coatings, and must use self-drying coatings. ； Paints containing iron red and red lead anti-rust pigments are not allowed on light metals such as aluminum and magnesium and their alloys. ； The cement surface needs to use a primer with good alkali resistance. ； The flexibility of the primer selected for plastic leather must meet the requirements. (2) Select appropriate primer varieties according to different usage environments and purposes. (3) The pigment filler content in the primer is high and prone to precipitation, so it should be stirred thoroughly before use to ensure a consistent pigment-base ratio, and stirred regularly during use. (4) The pre-treatment of the base material should be strictly in accordance with relevant standards. For example, the steel surface should be degreased and rust-free and reach Sa2 level or above. (5) The primer should be applied evenly and completely, and there should be no leakage or sagging. Generally, the film thickness of the anti-rust primer is controlled at 150~200um, and the coating should be done in a criss-cross pattern. At least two coats should be applied (the primary film-forming paint can be excluded, but two coats should be applied if possible) to avoid missed coatings. (6) The amount of primer diluent added cannot exceed 5% of the total amount, and the corresponding painting operation points and procedures should be strictly followed. (7) The next coating should be applied according to the drying time and optimal coating interval specified by the technical conditions. When using topcoats that contain strong solvents, the primer must be dry. To save energy and improve coating adhesion. The "wet-on-wet" construction process can be used, that is, spraying one coat of paint and then drying it for a while, so that the solvent in the paint film can only volatilize to a certain extent. When the paint film is still wet, spray a second coat of paint and then dry it once. “The wet-on-wet application method is limited to certain coatings, such as amino, perchlorethylene, polyurethane and epoxy coatings. (8) When selecting the intermediate layer and topcoat, strictly follow the coating matching principles to avoid the phenomenon of "biting the bottom". For example, polyurethane topcoat cannot be applied on alkyd primer, only oily and alkyd varnish, enamel, etc. can be applied. The matching principles of various coatings and optional matching coatings are shown in Table 1-10 in Chapter 1. In harsh and special anti-corrosion environments, epoxy, epoxy asphalt, and polyurethane two-component paints are generally used as primers. The topcoat can be either high-end polyurethane or chlorinated rubber paints, or alkyd and other enamels.

This post was last edited by mopeizhi on 2010-2-7 15:59 The basic item for quality inspection of paint coating projects is the appearance quality of the coating, including smooth coating and no sagging, blistering, cracks, rust spots, peeling off, etc. As a part of the quality of light industry, home appliances, and mechanical and electrical products, painting has higher requirements for coating quality, such as: No loss of gloss, powdering, gold-like appearance, mildew growth, etc. In fact, consumers have default indicators for the coating quality of industrial products, such as impact resistance, flexibility, and wear resistance. There are professional: Adhesion, scratch resistance, stain resistance, yellowing, gloss and color retention, aging resistance, etc. GB 50046-95 Anti-corrosion design specifications for industrial buildings Article 7.10.5: The primer, intermediate paint, topcoat, varnish, etc. of anti-corrosion coatings should be matched with coatings that are well combined with each other. The compilation of design specifications summarizes the characteristics of coatings used to protect substrates. The bottom, middle and top coatings are matched with products with different performance characteristics to achieve the designed total thickness of the coating film, which is the key for the coating to play a protective and decorative role. Coating matching is highly professional. The anti-corrosion design specifications for industrial buildings avoid outdated preaching and guide designers to design for specific projects based on technological development, product supply and successful experience. Avoid specifications with too many details that lag behind the development of the times and affect the correctness and applicability of the overall design document. Most of the standards are compiled, and the contents of the provisions are not distinguishable from correct to incorrect. They copy each other, such as paint coating matching, and cite a large number of matching examples of similar varieties, which lacks guiding significance. Matching between similar varieties is an introduction to the early stage of the development of paint manufacturers when there are not many product varieties. It is a phenomenon in the early stages of paint coating technology and is purely a relic of the technological development process. As technology evolves, these examples no longer apply. In anti-corrosion coating construction, the bottom, middle and surface are rarely matched with the same type of equipment, but various standards emphasize this point. Article 9.1.3 of GB 50212-91 "Code for the Construction and Acceptance of Anti-corrosion Engineering for Buildings" and Article 4.1.8 of SH 3022-1999 "Code for Design and Construction of Anti-corrosion Engineering for Petrochemical Equipment Pipelines", "Anti-corrosion coatings from different manufacturers and varieties must be determined through testing when used in combination. ”However, it did not specify what kind of test will be used to determine whether it can be matched. The successful coating matching experience of recent large projects can be used as a reference. GB 50212-2002 Article 9.1.3: The coating supplier must provide * * The current standard coating construction usage guide is used to propose supporting regulations. The rationality of the coating matching package focuses on the practical effect. What the test determines is only the adhesion between layers, and data can be obtained in a short period of time. Qualitative methods include the cross-hatch method and circle method, and quantitative methods include the pull-apart method. For other performance tests, it is difficult to draw a positive or negative conclusion within a few months. For adhesion testing between paint layers, the environmental conditions must be consistent with the actual working conditions. There is a big difference between the wet adhesion and dry adhesion of various coatings. The coating is immersed in a solution or soaked in water, and the interlayer matching in the atmosphere is two different things. For example, the wet adhesion of chlorosulfonated polyethylene coatings and alkyd coatings is very poor. If you ignore this, the test conclusions may be misleading. Regarding the adhesion between the base coating and the top coating, both of the above-mentioned standards propose that the base coating and the top coating be mixed in a ratio of 1:1 to form a transition layer. This was the construction practice of vinyl chloride coatings fifty years ago. The development information of many new varieties and new technologies shows that it is no longer applicable, and the compiler's approach of using nearby materials seems inappropriate. HG/T 20586-96 Chemical building coating design regulations 5.3.2.6 strip: When the selected coating needs to increase the coating thickness or need to improve the adhesion between coatings, a matching intermediate paint can be added. The drafters of this professional specification understand the progress of coating technology, and in one principled sentence, they explain the role of the intermediate layer coating and the principles of coating matching.

This post was last edited by mopeizhi at 2010-2-7 16:00 1. Surface treatment before painting All steel raw materials used in equipment manufacturing require surface rust removal before painting. And apply maintenance primer (shop primer) within the specified time range. Surface coating technology requirements and testing requirements for steel products 1. Before spray rust removal, thick rust layers should be eradicated. And remove grease dirt. After blasting or rust removal, the steel surface must be cleared of loose dust and debris. 2. There are two levels of rust removal for spray rust removal steel surfaces. Its text description is as follows: Sa2 thorough spray rust removal: There is no visible grease or dirt on the surface of the steel, and attachments such as scale, rust, paint coatings, etc. have been basically removed, and their residues should be firmly attached. Sa21/2 is a very thorough spray rust remover. There should be no visible grease, dirt, iron oxide paint layer and other attachments on the surface of the steel. Any remaining traces should be only dots or stripes of slight stains. 3. For the surface of rust-removed steel materials with manual power tools, there is a rust-removal grade, which is described in the following text:: St3 is a very thorough manual power tool rust remover. There is no visible grease and dirt on the surface of the steel, and there is no loose scale, rust, paint coating attachments. After rust removal, the exposed surface of the substrate should have a metallic luster. 4. The term "attachment" may include welding slag, welding spatter, soluble salts, etc. When the oxide scale, rust or paint layer can be peeled off from the steel surface with a metal putty scraper, it should be regarded as weakly adhered. 5. The surface of the steel to be inspected should be visually compared with the corresponding photos. Photos should be taken close to the steel surface. The evaluation should be carried out under well-dispersed sunlight or conditions with an illumination equivalent to artificial lighting. 6. The paint film thickness and coating selection during pretreatment are as follows:: a) Paint film (dry film) thickness: 15～25μm. b) Coating types: Inorganic zinc silicate (shop) primer, epoxy primer, epoxy zinc-rich primer, zinc phosphate primer, iron red epoxy primer, etc. c) The primer used must be of a matching paint type or compatible with the matching paint type primer. 2. Technical requirements 1. Before painting, the specified rust removal level standards must be met before painting is allowed. 2. In a mildly corrosive environment, when preparing to apply conventional paint, the surface rust removal level standard is Sa2 level. 3. When subject to chemical atmospheric corrosion, seawater corrosion, high-temperature oxidation, and when inorganic zinc-rich paint is used as a primer, the surface rust removal grade standard is Sa21/2. 4. The surface roughness of the steel must be controlled before painting. In addition to controlling the angular speed of the spray abrasive, the diameter of the pellets of the recycled abrasive must not be greater than 1.2mm. 5. After spraying or blasting rust removal, the surface of the object to be coated should be coated with the first layer of primer immediately after cleaning. The interval should not exceed 6 hours. If rust appears again on the surface, it should be reprocessed and painting is allowed only after reaching the specified standards. 6. If the surface of parts or materials coated with workshop maintenance primer is re-corroded due to welding, correction, scratches, exposure, etc., secondary rust removal must be carried out. After rust removal, the grade should reach St3 level. 3. Preparation before painting 1. The paint used should have a product certificate and be re-inspected according to the paint product acceptance rules. Paint that does not meet product quality is not allowed to be used. 2. For the same coating system, primer, putty, intermediate paint, topcoat, thinner, etc. must be used in conjunction. 3. Before opening the barrel of paint, confirm its brand, variety, color, batch number, etc., and record them. If the labeling is unclear, double check it. If there is a crust after opening the barrel, the crust should be removed carefully. If the paint is found to be expired, it should be identified and confirmed to be of reliable quality before construction. In case the paint deteriorates, it should be discarded and not used. 4. Some paint pigments are dense and easy to precipitate, so mechanical stirring is required to make the paint uniform. Before adding the two-component paint curing agent, stir it evenly first, and then stir it evenly again after adding the curing agent. 5. Mixing and curing two-component or three-component paint should be mixed according to the specified proportion. The standardized approach is as follows: ①Mix the paint evenly ； ②Pour in half of the hardener and mix well ； ③Pour in the remaining curing agent and mix well ； ④Then add diluent if necessary and mix well ； ⑤Place it for a certain period of time as required for maturation pre-reaction ； Be careful not to use it longer than specified. The aging time and mixing time shorten as the temperature rises, please pay attention to the manufacturer's instructions. Construction under the sun must be avoided during high temperature seasons. 6. Thinned paint can be used in a bucket without dilution. This must be avoided. * Inertial dilution. When diluent must be used, be sure to use the correct diluent. Excessive dilution will cause the paint to fail to reach the specified thickness, reduce drying and curing time, and cause sagging problems. Thinner can be added in the following situations:: ①When the temperature is low in winter, an appropriate amount of thinner can be added to reduce the viscosity of the paint. ； ②For hand or air spraying, thinner is required for ease of application. ； ③To deliberately reduce the film thickness, you can add an appropriate amount of diluent. 7. Filtration In order to remove large particles, crusts or other foreign matter that is difficult to disperse in the paint, filtration must be performed to ensure that the nozzle is not blocked. Standard practice is to pour it into another empty bucket through the filter. When spraying, add an 80-120 mesh sieve or filter to the suction port of the paint pump. Make sure the filter is clean. Clean with solvent after use for reuse next time. 4. Painting 1. Air circulation must be maintained in the construction area. There should be no flying dust and other foreign matter during the coating and curing process. During the painting construction process, try to ensure that the paint film is even and no leaks are allowed. Edges, corners, seams, welds and other parts should be painted first, and then large areas can be painted. 2. The surface of the machine product needs to be puttyed, and it should be done according to the process documents. When applying putty, you should apply primer first, and then apply putty after the primer dries. Putty is generally applied 1 to 2 times, with a thickness of about 0.5 to 1 mm each time, and the maximum total local thickness shall not exceed 5 mm. After the putty dries, the surface must be polished. After polishing, the surface of the putty should be flat, smooth, firm, and free of cracks. 3. Painting work should be carried out under climatic conditions. Painting shall not be carried out when the following conditions occur: a. During general painting, the ambient temperature is below 5 degrees Celsius or above 35 degrees Celsius. b. When painting in the open air, it rains, snows, fogs, frosts and strong winds occur. ； c.The surface temperature is lower than the dew point temperature plus 3 degrees Celsius ； For the dew point temperature value check, see the appendix reference part. d. The relative humidity of the surrounding environment is above 85%. ； 4. Defects such as pits, blisters, and pores appear on the surface of the casting. Must be filled with putty. There should be no peeling or cracking under the putty layer. 5. Before painting, the surface treatment quality should be checked. Painting cannot be carried out if the requirements are not met. During the coating construction process, defects such as sagging, wrinkling, blistering, cracking, peeling, and pinholes may occur. Corresponding technical measures must be taken to repair. 6. When the construction cannot be carried out according to the specified coating conditions due to environmental or other reasons, necessary technical measures must be taken and the coating quality can be guaranteed before construction can be carried out. Records must be kept of the measures taken. 7. When applying the coating in batches, the coating interval must be specified in the coating product manual. If the specified coating interval is exceeded, the surface of the previous coating should be roughened as necessary. 8. The wet coating should be protected from staining and damage. If the coating is stained and damaged, it should be repaired as required. 9. Where two coating films of different colors meet, the boundary must be clear, neat and standardized. 10. Assemble the painted parts on site, and the last coat of topcoat will be applied after the equipment is installed and debugged. 11. The coating construction method, whether brushing or spraying, must strictly abide by the operating procedures. The thickness of the coating film should comply with the design requirements. 12. Do not paint the friction surface of high-strength bolts under any of the following conditions. b. Embedded in concrete or in contact with refractory materials. c. It is a machined surface that is close to each other or has relative movement. d. Anchor bolts and their base plates. e. Seal the inner surface of the box and valve. f. Stainless steel parts, plated parts, non-metal parts and drawings indicate the parts not to be painted. g. Parts that require on-site processing. 5. Secondary painting 1. The rusty parts of the surface and the exposed joints, as well as the paint film damaged during the installation process, should be repaired and then repainted. 2. Before repairing, the surface should be cleaned, rust removed again, and then the surface should be blown clean with clean compressed air, and secondary painting and repair should be carried out according to the painting design requirements. 3. The coverage width of the repaired part to the surrounding coating should be no less than 50mm. When the damaged area is small, the repair area should be more than 1 times larger than the damaged area. 4. After the painting is completed, the components should be clearly marked according to the original number, name, code, etc. 6. Coating inspection and inspection 1. The appearance of the paint film should meet the following requirements: Defects such as pinholes, bubbles, cracks, bottom bite, bleeding, missed coating, sagging, partial peeling, etc. are not allowed in the primer, topcoat, and topcoat films. ； The topcoat surface should be smooth and even, with a full paint film and consistent color. The inspection method can be observed with the naked eye or with a magnifying glass after consultation. 2. Coating thickness testing should be carried out after each coating is dry. After all coating is completed, check the total thickness. Detection method: Use a paint film thickness gauge to detect, and every 10° (the paint film area is less than 10° shall be counted as 10°) as a point, and every 3 to 4M length of the slender body as a point, and measure 3 to 5 points at each point. The average thickness of each point measured at each location shall not be less than 90% of the total thickness of the specified coating, and shall not be higher than 120%. The minimum thickness of each point measured at each location shall not be less than 70% of the total thickness of the specified coating. 3. To detect the coating quality, the resistance of the coating to separate from the substrate can be evaluated. The evaluation of the resistance of the coating to separate from the substrate is carried out according to the following method.: Select six test panels with a specification of 200mm×200mm. After surface treatment, apply the same coating paint system as the new product. The resistance evaluation is carried out after the paint film has dried. After consultation, the evaluation can be carried out by using the cross-hatch method or the cross-hatch method. cross method: Use a sharp blade or safety blade to mark a cross with an angle of 60° on the surface of the test panel. The knife mark should be cut to the steel plate, and then affix a professional pressure-sensitive tape with a width of 25mm to make the tape close to the paint film, and then quickly pull it up by hand. If the total width of the coating on both sides of the knife mark is peeled off, it is qualified if the total width does not exceed 2mm. Cross-hatch method: The evaluation shall be carried out in accordance with the relevant provisions of the "Cross-cut Test of Paint and Varnish Films" (GB/T9286).

This post was last edited by mopeizhi on 2010-2-7 16:03 The spraying method adopts the "alternating method", that is, the method of alternating vertical and horizontal spraying. The specific control points are:: · It is necessary to strictly follow the technical instructions of the carbon paint manufacturer. The raw materials should be stirred evenly without visible impurities and filtered with a filter. · Before spraying, sand the surface with sandpaper and rinse the surface with water. Spray after the moisture is removed. When spraying

This post was last edited by mopeizhi on 2010-2-7 16:04. Master the ratio of two-component or multi-component paints. It is best to apply the primer by brush. . . . P.S.: Most of my friends have similar answers. They all seem to be from Baidu?

This post was last edited by mopeizhi on 2010-2-7 16:05 Primer is the coating under the middle layer or top layer in the coating system, or the coating directly applied to the surface of the substrate. The primer must have good protective properties for the substrate, and have good adhesion and mechanical strength. It serves as an intermediary layer between the surface to be painted and other coatings, so that the two can be firmly combined to form a solid covering layer. The primer must have a high ability to prevent rust and fill the surface of the material. Anti-rust pigments are generally added. Since primers are generally not directly exposed to the atmosphere, their weather resistance requirements are not high. Various resin varieties have corresponding primers, the most commonly used ones are: Epoxy primer, asphalt primer, alkyd primer, phenolic primer, chlorinated rubber primer, vinyl primer, polyurethane primer, epoxy asphalt primer, etc. Different types of coatings are used according to the coating requirements and purpose of use. The method of applying primer may be selected according to the construction methods in Chapter 3, but the most commonly used methods are brushing and spraying. Brushing primer is especially suitable for construction on corners and other complex-shaped parts to increase coating adhesion. ； High-pressure airless spraying can apply a relatively thick anti-corrosion coating at one time and is suitable for large-area construction. The following points should be noted when applying primer. (1) Select an appropriate primer according to the material of the object to be coated. The general principle is: Wood products, leather shoes, paper, textiles and thermoplastics cannot use high-temperature baking film-forming coatings, and must use self-drying coatings. ； Paints containing iron red and red lead anti-rust pigments are not allowed on light metals such as aluminum and magnesium and their alloys. ； The cement surface needs to use a primer with good alkali resistance. ； The flexibility of the primer selected for plastic leather must meet the requirements. (2) Select appropriate primer varieties according to different usage environments and purposes. (3) The pigment filler content in the primer is high and prone to precipitation, so it should be stirred thoroughly before use to ensure a consistent pigment-base ratio, and stirred regularly during use. (4) The pre-treatment of the base material should be strictly in accordance with relevant standards. For example, the steel surface should be degreased and rust-free and reach Sa2 level or above. (5) The primer should be applied evenly and completely, and there should be no leakage or sagging. Generally, the film thickness of the anti-rust primer is controlled at 150~200um, and the coating should be done in a criss-cross pattern. At least two coats should be applied (the primary film-forming paint can be excluded, but two coats should be applied if possible) to avoid missed coatings. (6) The amount of primer diluent added cannot exceed 5% of the total amount, and the corresponding painting operation points and procedures should be strictly followed. (7) The next coating should be applied according to the drying time and optimal coating interval specified by the technical conditions. When using topcoats that contain strong solvents, the primer must be dry. To save energy and improve coating adhesion. The "wet-on-wet" construction process can be used, that is, spraying one coat of paint and then drying it for a while, so that the solvent in the paint film can only volatilize to a certain extent. When the paint film is still wet, spray a second coat of paint and then dry it once. “The wet-on-wet application method is limited to certain coatings, such as amino, perchlorethylene, polyurethane and epoxy coatings. (8) When selecting the intermediate layer and topcoat, strictly follow the coating matching principles to avoid the phenomenon of "biting the bottom". For example, polyurethane topcoat cannot be applied on alkyd primer, only oily and alkyd varnish, enamel, etc. can be applied. The matching principles of various coatings and optional matching coatings are shown in Table 1-10 in Chapter 1. In harsh and special anti-corrosion environments, epoxy, epoxy asphalt, and polyurethane two-component paints are generally used as primers. The topcoat can be either high-end polyurethane or chlorinated rubber paints, or alkyd and other enamels.

1. Choose the right paint and make it strictly according to the technical ratio to ensure that the various paints are mixed evenly； 2. Ensure that the working surface is clean and dry, and pay attention to the working environment in a moderately small environment during construction.

1. Mix the red lead anti-rust paint and control the viscosity, consistency and dilution of the paint. Stir thoroughly when mixing to make the paint color and viscosity uniform. ?? 2 When applying the first layer of primer, the painting direction should be consistent and the connections should be neat. ?? 3 When painting, the principle of frequent application and short brushing should be adopted to prevent the brush from carrying too much paint and causing it to fall off. ?? 4. After the first coat is finished, a certain time gap should be maintained to prevent the second coat from being applied before the first coat is dry. This will cause the paint to flow, wrinkle, and reduce the quality. ?? 5. After the first coat is dry, apply the second coat. The direction of the second coat should be perpendicular to the direction of the first coat, so that the thickness of the paint film will be uniform. ?? 6 It takes at least 4 to 8 hours after the primer is applied to reach surface dryness. Topcoat should not be applied before surface dryness.

1. Mix the red lead anti-rust paint and control the viscosity, consistency and dilution of the paint. Stir thoroughly when mixing to make the paint color and viscosity uniform. ?? 2 When applying the first layer of primer, the painting direction should be consistent and the connections should be neat. ?? 3 When painting, the principle of frequent application and short brushing should be adopted to prevent the brush from carrying too much paint and causing it to fall off. ?? 4. After the first coat is finished, a certain time gap should be maintained to prevent the second coat from being applied before the first coat is dry. This will cause the paint to flow, wrinkle, and reduce the quality. ?? 5. After the first coat is dry, apply the second coat. The direction of the second coat should be perpendicular to the direction of the first coat, so that the thickness of the paint film will be uniform. ?? 6 It takes at least 4 to 8 hours after the primer is applied to reach surface dryness. Topcoat should not be applied before surface dryness.