Paint knowledge | what is the formulation of EPC coating? How to improve the permeability of EPC coating

Core tip: EPC coating is generally composed of refractory, binder, carrier (solvent), surfactant, suspending agent, thixotropic agent and other additives All kinds of components are mixed together and play an important role in coating and pouring Lost foam coating formulation 1, bauxite 90%, quartz powder 10%, phenolic resin 2%, white emulsion 2%, calcium bentonite 3%, laundry powder 0.1%, isopropanol 0.1%, appropriate amount of water; 2, silica sand powder and bauxite 2:3, (refractory 100%), GM-1 resin 2%, silica sol 3%, lithium bentonite 1%, cmc1.5 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: EPC coating is generally composed of refractory, binder, carrier (solvent), surfactant, suspending agent, thixotropic agent and other additives All kinds of components are mixed together and play an important role in coating and pouring Lost foam coating formulation 1, bauxite 90%, quartz powder 10%, phenolic resin 2%, white emulsion 2%, calcium bentonite 3%, laundry powder 0.1%, isopropanol 0.1%, appropriate amount of water; 2, silica sand powder and bauxite ratio 2:3, (refractory 100%), GM-1 resin 2%, silica sol 3%, lithium bentonite 1%, cmc1.5%, flat as 0.3%, water reducer 0.5%, appropriate amount of water; 3 Bauxite 60%, flake graphite 40%, silica sol 4%, binder 4%, bentonite 1% iron oxide 3%, cmc3%, n assistant 0.5%; the sum of the above formulas is 100% Determination of coating thickness of EPC coating: casting weight (kg) coating thickness (mm) application 500 1.5 ~ 2.0 large cast iron and steel casting EPC coating performance The performance of EPC coating includes many indexes: light, air permeability, fire resistance, heat insulation, cold and hot resistance, moisture absorption, cleaning, coating hanging, dribbling and suspension These performance indexes can be divided into two categories: working performance and process performance The strength, air permeability, fire resistance, heat insulation and quench resistance of the coating are all working properties, while the coating hanging, dribbling and suspension properties of the coating are technological properties Foaming of EPC coating the reason for foaming of EPC coating is that there are polymer molecules in the coating and the components that are easy to dry into film When the coating is thick and the drying speed is too fast, the polymer molecular chain cross-linking forms the film too early, and the gas evaporated by the water under the film in the drying process can't smoothly expand through the film, so the coating bulges up; In the process of coating application, due to the insufficient friction and infiltration between the coating slurry and the surface of the white mold, the gas on the surface of the white mold could not be completely "expelled" and eliminated When the pattern was baked and heated, the gas expanded and the coating was bubbled After the coating of EPC coating, the coating bubbles directly affect the coating effect, resulting in poor casting quality, rising defective rate and greatly increased cost, which many foundry enterprises do not want to see Therefore, when using the coating, it is necessary to operate strictly according to the steps, so that the coating can fully play its role How to improve the permeability of EPC coating? 1 Mix different kinds and sizes of refractory aggregate reasonably The type and size of refractory aggregate have a great influence on the air permeability of the coating Generally speaking, the permeability of coating is very poor when a certain aggregate is used alone, but it is better when different refractory aggregates are used together If bauxite is compounded with quartz powder, good air permeability can be obtained At the same time, the particle shape of aggregate has a great influence on the permeability of coating Spherical particles (quartz and corundum) form exposed micropores, while sheet particles (talc and mica) form concealed micropores Cellular structure (perlite) and fibrous structure (asbestos, vermiculite) filler form disordered structure, forming loose porous structure and high permeability The air permeability of the coating can be adjusted within a certain range by reasonable mixing of different kinds of aggregate 2 Select organic binder The decomposition of organic binder at high temperature can form some cavities, which can increase the high temperature permeability of the coating However, the coating with high temperature binder such as silica sol and water glass has poor air permeability 3 Add appropriate oxidant When the foam mold is not completely decomposed at high temperature, it will deposit some carbon on the surface of the coating and block the exhaust passage, thereby reducing the high temperature permeability of the coating Adding some oxidants can accelerate the decomposition of foam plastic mold, thereby preventing carbon deposition and increasing the air permeability of the coating The air permeability of EPC coating is enhanced, which has a significant effect on improving the quality of castings 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,