Coating process: industrial coating process

Core tips: 1 Climatic conditions 1 The main factor to be paid attention to when coating high-performance anticorrosive coating is the condition of steel plate surface Humidity of steel plate and atmospheric environment during coating Generally, the coating work should be carried out under the climatic conditions of above 5 ℃ and below 85% relative humidity When the surface is affected by rain or ice and snow, coating is not allowed 2 Measure the temperature of the steel plate with a thermometer, measure the relative humidity with a hygrometer, and then calculate the dew point When the temperature difference between steel plate and dew point is above 5 ℃, the curing speed of epoxy type and epoxy asphalt antirust paint will be greatly slowed down, even Paint knowledge how about Akzo Nobel Powder Coating Recommended introduction: powder coating is a kind of coating with different form from general coating, which is in powder form It is a new type of coating, because of its own advantages and more and more known by people Let's introduce Akzo Nobel Powder coating Akzo Nobel Powder coating is a cost-effective coating solution, which can be applied to different kinds of products After the treatment of static electricity and fire baking, a tough and durable coating surface will be formed, with the least impact on the environment Since the introduction of this technology, powder coating has been able to continue to maintain the Coating home news: 1 Climatic conditions 1 The main factors to be noticed when coating high-performance anticorrosive coating are the condition of steel plate surface Humidity of steel plate and atmospheric environment during coating Generally, the coating work should be carried out under the climatic conditions of above 5 ℃ and below 85% relative humidity When the surface is affected by rain or ice and snow, coating is not allowed 2 Measure the temperature of the steel plate with a thermometer, measure the relative humidity with a hygrometer, and then calculate the dew point When the temperature difference between the steel plate and the dew point is above 5 ℃, the curing speed of epoxy type and epoxy asphalt antirust paint is greatly slowed down, or even stops curing, so it can not be used, but it can be applied by sections in the paint shop with temperature rise device; or it can also be applied dry chlorinated rubber type anti-corrosion paint under the condition of no ice frost on the surface below 0 ℃ 3 When the construction is carried out under severe conditions with temperature above 30 ℃ The solvent volatilizes very quickly When airless spraying, the solvent in the paint volatilizes between the nozzle and the surface of the coating to form dry spraying In order to avoid dry spraying, the spray gun should be as close to the object surface as possible, and spraying should be carried out as vertically as possible If drying still occurs after this measure is adopted, a solvent no more than 5% of the weight of the paint itself can be added for dilution to solve the problem 2、 Preparation before painting 1 Before painting, the type, model and specification of the paint used shall be checked to see whether they meet the requirements of construction technical conditions Unqualified or deteriorated paint shall not be used 2 Before painting, the basic composition, performance and construction method of the paint shall be understood, and appropriate painting tools shall be selected and determined according to the respective construction requirements of the paint 3 Due to the different proportion of various components in the paint, generally after the paint is stored, there will be different degree of precipitation Therefore, the paint must be mixed to be completely uniform before painting If paint skin or particles are found, 80-120 mesh screen shall be used for filtration 4 Epoxy series, chlorosulfonated polyethylene and other series are two cans of coating with two components of a and B Before use, it must be mixed evenly according to the specified weight ratio After mixing, it can be used only after being matured for 30 minutes The prepared materials shall be calculated and used according to the coating area, and then mixed If the mixing proportion is wrong, the drying performance and antirust paint performance will be affected If too much material is prepared at one time, it will cause gelatinization waste 5 Generally, the paint has been adjusted to the viscosity suitable for construction at the time of delivery, so it is unnecessary to dilute However, under the condition of too high and too low temperature, a proper amount of diluent can also be added to achieve the ideal coating viscosity, but the amount of diluent should not exceed 5% of the weight of the paint itself 6 The storage time indicated in the instructions is the minimum If the storage time is exceeded, it can still be used after passing the re inspection 3、 Painting 1 When painting with paint brush, the direction of painting shall be first downward and then left and right The paint brush shall not be dipped too much to prevent dripping When coating heavy antirust paint, the paint brush distance shall not be too large to avoid too thin paint film In case of pitted surface, rough edge, bending, concave convex and other parts, special attention should be paid It is better to precoat one layer first 2 The paint on the drum shall be evenly distributed When roller coating is used for coating, the rolling speed shall be kept to a certain extent Do not press the roller too hard too fast The protruding parts such as welds and cuts shall be handled with care It is better to precoat one layer first 3 High pressure airless spraying is the fastest coating method, and can obtain a very thick film Therefore, in order to achieve the specified film thickness, it is best to use airless spraying construction method In the actual coating, it shall be applied from top to bottom and then left and right Or the vertical and horizontal spraying method of first left and right then up Using airless spraying requires a higher skill The spray gun and the coated surface should be kept at a horizontal distance During operation, the spray gun should be prevented from swinging for a long distance or arc 4 Strengthen the lining process, apply the primer to the clean pipe body as soon as possible (referring to the epoxy coal tar pitch coating used for the pipe), then apply the finishing coat and wind the glass cloth When spiral winding and winding the glass cloth, it must be tight and wrinkled, with no gap and edge of 20 mm Construct layer by layer in order to reach the structure specified in the design The winding direction shall be opposite to the first layer to improve the tightness of the whole coating It is required that the mesh of glass cloth shall be covered by the top coat, and the surface shall be bright paint film, then it shall be lifted to the site for stacking, and it shall be naturally dry 5 If the construction task is urgent and can't wait, the lining layer can be lowered into the ditch or even into the water if it doesn't meet the requirements of practical work, but the outer wall is better to be wrapped with a dense woven glass cloth protection layer, and mechanical bruise is avoided as far as possible As long as the uncured lining layer is not damaged when running into the ditch, it will gradually solidify in the soil or water, providing good protection performance 6 The lining layer can be dried after being placed at a temperature of about 25 ℃ for 48h During this period, protection conditions shall be provided, such as no rain, sun, etc 7 When the primer is applied, the interval time to be dried must be enough to give full play to the high adhesion strength of the epoxy coal tar pitch paint, and it is not allowed to paint on it when it is not dry 8 Control of the thickness of the paint film The thickness of each paint film listed in this manual refers to the thickness of the dry paint film In order to give full play to the best performance of high-performance anticorrosive paint, it is very important to have enough film thickness Therefore, the film thickness must be strictly controlled The thickness of each coating film obtained by painting with brush or roller is light and thin, and the number of coating layers is at least twice as many as that of high-pressure airless spraying, so as to reach the specified thickness For edges, corners, welds, cuts and other parts, before spraying, a layer of paint shall be applied first, and then a large area of paint shall be applied to ensure the film thickness of the protruding parts During construction, coating shall be carried out according to the instructions, and wet film thickness gauge shall be often used to measure the thickness of wet film If the film thickness fails to meet the requirements, it must be repaired 9 The coating interval of different types of coatings is different The construction shall be carried out according to the requirements of each coating In particular, it should be pointed out that the interval time of epoxy series coating should not exceed the longest interval time in the specification Otherwise, it will affect the adhesion between the film layers and cause the film to fall off 10 The amount used in this instruction is the theoretical value, which refers to the paint consumption per unit area calculated under the theoretical conditions when the film thickness is uniform However, the actual consumption in painting depends on the thickness of the film, the painting method and the rough condition of the coated surface When estimating the actual consumption of paint, the consumption of paint should be increased by 30% - 80% in addition to the theoretical use Precautions and safety measures 1 The paint shall be stored in a place with low temperature, ventilation and dryness, away from the heat source, avoiding direct sunlight and isolating the fire 2 It is forbidden to smoke or use open fire in the batching room where the opened paint, curing agent and diluent are stored Operators should try to avoid staying too long 3 Before painting, it is necessary to check whether the required lighting, ventilation, scaffolding and other equipment are complete and reliable Whether all painting and welding have been completed, and try to ensure that the welding work does not damage the painted film 4 When the epoxy series or chlorinated rubber series are used as the inner wall of the dissolver, especially the closed container, sufficient ventilation must be carried out during coating and before the paint film is completely dry 5 Protective measures shall be taken before the paint film is completely dried and solidified Avoid being washed by rain or other liquids, or trampled by operators 6 When painting on the construction site or in the painting workshop, various preventive measures must be taken to prevent accidents and provide necessary personal protection for construction personnel 7 The construction site shall be provided with good ventilation conditions The wires must be installed according to the explosion-proof level The starting device and power distribution equipment of the motor shall be explosion-proof Explosion proof lighting lamps are also used In order to avoid electrostatic accumulation, the spraying chamber and spray gun shall be grounded when spraying in the drinking water tank on the inner wall of the container 8 Welding, cutting, smoking or ignition are strictly prohibited at the paint construction site Avoid metal friction or electrical sparks, so as not to cause explosion or combustion If the paint is on fire, do not put out the fire with water Foam should be used and carbon dioxide extinguishing agent should be put out 9 When using hand or pneumatic tools to remove rust or old paint film, in order to avoid eye injury and dust inhalation, wear protective eyes and dust masks 10 In order to prevent paint splashing on the skin or in the eyes, work clothes, gloves and protective glasses must be worn during construction If the paint is splashed on the skin, it should be washed with soap and water, and it is better not to use solvent If the paint splashes into the eyes, immediately wash with water for 10 minutes Then go to the doctor immediately 11 Prevent the inhalation of solvent gas and paint mist during spraying When painting in a place with good ventilation conditions, gas mask can be used When construction is carried out in a place with poor ventilation, such as the water tank on the inner wall of the container, gas supply hood or mask must be worn Personnel who do not wear the air supply protective cover shall not be exposed to paint mist or unknown conditions, just in case 12 If the operators feel dizzy, headache, nausea, vomiting and other discomfort, they should immediately go to the fresh air place, and continue painting until the ventilation of the original working place is improved If the person faints due to inhalation of excessive solvent or paint mist, he / she should be moved to a place with fresh air immediately Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,