Coating process: water based coating spraying construction process

Core tip: water-based coating is a kind of coating with water as solvent or dispersion medium The water-based coating includes water-soluble coating, water diluting coating and water dispersing coating (emulsion coating) The water-soluble coating is based on water-soluble resin as film-forming material, polyvinyl alcohol and its various modifiers as representatives, in addition to water-soluble alkyd resin, water-soluble epoxy resin and inorganic high polymer water-based resin Spraying method is one of the most important methods in the construction of water-based coating The thin and uniform coating can be obtained by spraying on the surface of the object For the different geometry, there are holes, gaps and bumps, the coating can be divided into Application scope and advantages of roller ceramic coating Recommended introduction: the surface of ceramic rubber plate used for roller ceramic coating is cast into durable rubber plate by hundreds of independent small ceramic pieces Each ceramic piece has raised characteristics Under general conveyor belt pressure, thousands of unique cast bumps can produce positive traction, prevent slipping and extend the service life of conveyor belt roller At the same time, the bottom layer adopts high-quality rubber, which has strong elasticity and can play a good impact resistance role The scope of application of roller ceramic coating is one three six 83857180 (the same as V) 1 Roller coating in extremely harsh working environment 2 The belt joint is not suitable for fixing with iron buckle; 3 It is suitable for leather Coating home news: water-based coating is used as a solvent or as a dispersing medium The water-based coating includes water-soluble coating, water diluting coating and water dispersing coating (emulsion coating) The water-soluble coating is based on water-soluble resin as film-forming material, polyvinyl alcohol and its various modifiers as representatives, in addition to water-soluble alkyd resin, water-soluble epoxy resin and inorganic high polymer water-based resin Spraying method is one of the most important methods in the construction of water-based coating The thin and uniform coating can be obtained by spraying on the surface of the object For different geometry, there are holes, gaps and uneven places, and the coating can be evenly distributed For spraying large objects, this method is faster and more effective than painting However, some operating skills should be mastered in the construction of spraying method: first, adjust the coating to the proper spraying viscosity with clean water, and measure it with a - 4 viscometer The proper viscosity is generally 20-30 seconds If there is no viscometer for a while, visual inspection can be used: stir the paint with a stick (iron bar or wood bar) and then lift it to a height of 20cm to stop for observation If the paint liquid continues to line in a short time (several seconds), it is too thick; if the line breaks immediately from the upper edge of the barrel, it is too thin To stay at a height of 20cm, the paint liquid will form a straight line, which will break and flow into drops in an instant This viscosity is more appropriate Second, the air pressure is best controlled at 0.3-0.4 MPa (3-4 kgf / cm2) If the pressure is too small, the paint liquid will not atomize well, and the surface will form pockmarks; if the pressure is too large, it is easy to flow and hang, and the paint mist is too large, which wastes materials and affects the health of the operator Third, the distance between nozzle and object surface is generally 300 mm ~ 400 mm When it is too close, the paint film is easy to flow and hang; when it is too far, the paint mist is uneven, and the spray nozzle is far away from the object surface, and the paint mist disperses on the way, causing waste The specific distance should be adjusted according to the type of coating, viscosity and air pressure The spraying distance of slow drying paint can be a little longer, that of fast drying paint can be a little closer; when the viscosity is thick, it can be a little longer, when the viscosity is thin; when the air pressure is high, it can be a little farther, and when the pressure is small, it can be a little closer; the so-called "near point and far point" refers to the adjustment of the small range between 10 mm and 50 mm, if it is beyond this range, it is difficult to obtain the ideal paint film Fourth, the spray gun can be moved up and down, left and right It is better to operate uniformly at a speed of 10-12 M / min the spray nozzle should be straight on the surface of the object, and oblique spray should be minimized When spraying to both ends of the object surface, the hand to pull the trigger of the spray gun should be loosened quickly to reduce the paint mist Because the two ends of the object surface are often subject to more than two spraying, which is the most likely place to cause sagging Fifth, when spraying, the next layer should be pressed to 1 / 3 or 1 / 4 of the previous layer, so as to avoid leakage When spraying quick drying paint, it is necessary to finish spraying in sequence at one time, and the effect of re spraying is usually not ideal Sixth, when spraying in the open outdoor place, pay attention to the wind direction (it is not suitable for operation in case of strong wind), and the operator shall stand in the downwind direction to prevent the paint mist from being blown to the sprayed paint film to cause the ugly granular surface Seventh, the order of spraying is: first difficult, then easy, first inside and then outside First high place, then low place, first small area, then large area, so as not to cause the spray spray to the spray film and damage the spray film 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,