​What are the characteristics of construction machinery coatings

With the development of society and the improvement of people's aesthetic concept, users put forward higher requirements for the performance of construction machinery, while the quality of its appearance requirements are higher and higher. Especially in recent years, the export volume of construction machinery products has expanded, so all construction machinery manufacturers have begun to attach importance to "surface meaning", and strive to shorten the appearance of similar products with foreign quality gap, improve competitiveness in the international market. The construction of coatings and coatings is the main link to realize the appearance quality of construction machinery products, and the correct selection of coatings and construction is the key

.
engineering mechanical coatings should have the following characteristics:
(1) very little permeability to water, oxygen and corrosive media; (2) strong and long-lasting adhesion to the substrate; (3) good rust protection, decorative properties; (4) special properties, such as insulation, conductivity, thermal insulation, etc.;
In order to ensure the above performance of industrial energy conservation and environmental protection needs
under the conditions of ensuring the above-mentioned performance, coatings should also have low-temperature fast-drying, environmental protection and energy-saving performance, such coatings should also be particularly suitable for the production of small batch of construction machinery parts and machine coating.
the current domestic construction machinery using paint is generally epoxy primer, polyurethane paint. The former has good anti-rust performance, while the latter has good decorative performance.
, acrylic latex paint:
acrylic latex paint is generally composed of acrylic emulsions, pigments, water, additives. With moderate cost, excellent weather resistance, good performance adjustability, no organic solvent release and other advantages, is a very rapid development of a class of coating products. Mainly used in the building's interior and exterior wall coating, leather coating and so on. Recently, there have been new varieties of wood with latex paint, self-linked latex paint and so on. Acrylic latex paint can be divided into pure propylene, phenyl, silicone, acetate and other varieties according to the emulsion.
II, solvent-based acrylic paint:
solvent-based acrylic paint has excellent weather resistance, high mechanical properties, is currently a rapid development of a class of coatings. Solvent-based acrylic paint can be divided into self-drying acrylic paint (thermoplastic type) and cross-cured acrylic paint (thermoso-cured type), the former belongs to non-converted coatings, the latter belongs to the conversion paint. Self-drying acrylic coatings are mainly used in architectural coatings, plastic coatings, electronic coatings, road line coatings, etc. , with the advantages of rapid drying, easy construction, protection and decorative effect. The disadvantage is that the solid content is not easy to be too high, hardness, elasticity is not easy to take into account, a construction can not get a very thick coating film, coating film plumpness is not ideal. Cross-linked cured acrylic paint mainly acrylic acrylic paint, acrylic polyurethane paint, acrylic alcohol paint, radiation-cured acrylic paint and other varieties. Widely used in automotive coatings, electrical coatings, wood coatings, architectural coatings and so on. Cross-cured acrylic coatings generally have a high solid content, a coating can get a very thick coating film, and good mechanical performance, can be made into high weather resistance, high plumpness, high elasticity, high hardness of the coating. The disadvantage is two-part coating, construction is more troublesome, many varieties also need heating curing or radiation curing, environmental conditions are relatively high, generally need better equipment, more skilled coating skills.
, polyurethane paint:
polyurethane coating is currently a more common type of coating, can be divided into two-group polyurethane coating and single-group polyurethane coating. Two-component polyurethane coatings are generally composed of isocyanate prepolymers (also known as low-molecular urethane polymers) and hydroxy resins, commonly referred to as curing agent components and main agent components. There are many varieties of this type of coating, the application range is also very wide, according to the hydroxyl-containing parts can be divided into acrylic polyurethane, alcoholate polyurethane, polyurethane polyurethane, polyether polyurethane, epoxy polyurethane and other varieties. Generally has good mechanical performance, high solid content, all aspects of performance are better. Is currently very promising a class of paint varieties. The main application directions are wood coatings, automotive repair coatings, anti-corrosion coatings, floor coatings, electronic coatings, special coatings and so on. The disadvantage is that the construction process is complex, the construction environment is very demanding, paint film is easy to produce ills. Single-group polyurethane coatings mainly have ammonia oil coatings, moisture-cured polyurethane coatings, closed polyurethane coatings and other varieties. The application surface is not as wide as the two-part coating, mainly used in floor coatings, anti-corrosion coatings, pre-rolled coatings, etc., its overall performance is not as comprehensive as the two-part coatings.
, nitro paint:
is currently more common wood and decoration paint. The advantage is that the decorative effect is better, the construction is simple, the drying is fast, the requirements of the coating environment is not high, has a better hardness and brightness, is not easy to appear paint film ills, easy to repair. The disadvantage is that the solid content is low, need more construction channel number to achieve better results, durability is not very good, especially the internal nitro paint, its preservation of color is not good, the use of a little longer will be prone to such as loss of light, cracking, color change and other ills; Nitro paint's main film-forming material is nitric cotton-based, with aolic acid resin, modified pine resin, acrylic resin, amino resin and other hard and soft resins together. Generally also need to add phthalates, diasine, castor oil oxidation and other plasticizers. Solvents are mainly esters, ketones, alcohol ethers and other real solvents, alcohols and other solvents, as well as benzene and other thinners. Nitro paint is mainly used in wood and furniture coating, home decoration, general decorative coating, metal coating, general cement coating and so on.
5, epoxy paint:
epoxy paint is a very rapid development in recent years, a class of industrial coatings, generally speaking, the composition of the composition contains more epoxy groups of paint collectively known as epoxy paint. The main varieties of epoxy paint are two-component coatings consisting of epoxy resins and curing agents. There are some other single-part self-drying varieties, but its performance and two-part coatings have a certain gap. The main advantages of epoxy paint are strong adhesion to cement, metal and other inorganic materials, the coating itself is very resistant to corrosion, mechanical performance is excellent, wear-resistant, impact-resistant, can be made into solvent-free or high solid coating, resistant to organic solvents, heat- and water-resistant, non-toxic coating. The disadvantage is that the weather resistance is not good, sunlight exposure for a long time may appear powdering phenomenon, so can only be used for primer or interior paint; Epoxy resin coatings are mainly used in floor coating, automotive primers, metal corrosion protection, chemical corrosion and so on.
6, amino paint:
amino paint is mainly composed of two parts, one is the amino resin components, mainly butyl etherized melamine formaldehyde resin, methyl etherized melamine formaldehyde resin, butyl etherized formaldehyde resin and other resins. The second is the hydroxy resin part, mainly short and medium-short oil alcoholic acid resin, hydroxypropyl acid resin, epoxy resin and other resins. In addition to the amino paint used in wood coatings of the acrylic resin paint (commonly known as acid curing paint), the main varieties need to be heated and cured, the general curing temperature is more than 100 degrees C, curing time is more than 20 minutes. After curing the paint film performance is excellent, the paint film hard plump, bright, strong and durable, with a good decorative and protective role. The disadvantage is that the coating equipment requirements are high, high energy consumption, not suitable for small-scale production. Amino paint is mainly used in automotive paint, furniture coating, household appliances coating, a variety of metal surface coating, instrumentation and industrial equipment coating.
, alicic acid paint:
aolate paint is mainly composed of aolic acid resin. It is currently the largest domestic production of a class of coatings, with cheap, simple construction, the construction environment requirements are not high, coating film plump hard, durability and weather resistance is better, decorative and protective are better and other advantages. The disadvantage is that the drying is slow, the coating film is not easy to meet the higher requirements, not suitable for high decorative occasions. Aliclic paint is mainly used in general woodware, furniture and home decoration coating, general metal decoration coating, low requirements of metal anti-corrosion coating, general agricultural machinery, automobiles, instrumentation, industrial equipment coating and so on.
8, unsaturated polyester paint:
unsaturated polyester paint is also a recent rapid development of a class of coatings, divided into air-drying unsaturated polyester and radiation curing (light curing) unsaturated polyester two categories. The main advantage is that you can make solvent-free paint, a brush can get a thicker paint film, the coating temperature requirements are not high, and paint film decoration effect is good, paint film tough and wear-resistant, easy to maintain. The disadvantage is that when curing, the paint film shrinkage rate is large, the adhesion to the substrate is prone to problems, air-drying unsaturated polyester generally needs polishing treatment, procedures are more cumbersome, radiation curing unsaturated polyester on the coating equipment requirements are higher, not suitable for small-scale production. Unsaturated polyester paint is mainly used in furniture, wooden flooring, metal corrosion and so on.
, vinyl paint:
vinyl paint including chlorine vinegar co-polyester paint, polyethylene alcohol butyl paint, perchloroethylene, perchloroethylene, chlorine polyethylene paint and other varieties. The main advantages of vinyl paint are weather resistance, chemical corrosion resistance, water resistance, insulation, mold resistance, flexibility is good. Its disadvantages are mainly manifested in the general heat resistance, not easy to make high solid paint, mechanical properties in general, poor decorative performance and so on. Vinyl paint is mainly used in industrial anti-corrosion coatings, electrical insulation coatings, phosphating primers, metal coatings, external coatings and so on.
, phenolic paint:
phenolic resin is a product of phenol and aldehyde in the presence of catalysts. Paint industry mainly uses oil-soluble phenolic resin paint. The advantages of phenolic paint are fast drying, bright and hard paint film, water resistance and chemical corrosion resistance. The disadvantage is easy to turn yellow, should not be made of light paint, weather resistance is not good. Phenol paint is mainly used in anti-corrosion coatings, insulation coatings, general metal coatings, general decorative coatings and so on.
surface treatment is one of the important processes of anti-rust coating. The quality of anti-rust coating of construction machinery depends to a large extent on the way the surface is treated.
, according to Imperial Chemical, coating life is limited by three factors: 60% surface treatment, 25% coating construction, and 15% quality of the coating itself.
different surface treatment methods for different parts in the engineering machinery industry.
mechanical cleaning can effectively remove rust, welding slag, oxidizing skin, eliminate welding stress, increase the anti-rust coating film and metal substation binding force, thereby greatly improving the rust-proof quality of construction machinery components. Mechanical cleaning standards require ISO8501 - 1 : Sa2 in 1988 . Level 5. Surface roughness should reach 1/3 of the thickness of the rust-proof coating. The steel pellets used for spraying and blasting should meet the GB6484 requirements.
surface treatment of thin plate stamping parts is called chemical surface treatment. Process is:
manual pre-treatment→ hot water washing→ pre-skimming→ degreasing→ industrial washing one→ industrial washing two→ surface adjustment→phosphate→ industrial washing three→ The process of →proal water washing four→ pure water washing one→ pure water washing two→ pour water → drying
the above-mentioned process can also be adjusted according to the oil and rust of sheet stamping parts, or do not use the picklash process, or do not use the pre-skimming process. Degreasing and phosphation are the key processes in the chemical treatment process, which directly affect the quality of the chemical treatment of work parts and the quality of rust-proof coatings. The process parameters and related auxiliary equipment are also important factors that affect the quality of surface treatment.
In order to remove all kinds of foreign objects attached to the surface of the object (e.g. oil, rust, dust, old paint film, etc.), provide a good substrate suitable for coating requirements, to ensure that the coating film has good corrosion resistance, decorative properties and certain special functions, the surface of the object must be pre-treated before coating. The work done with this treatment is collectively referred to as pre-coating (surface) treatment or (surface) pre-treatment.
because of the wide range of construction machinery, specifications, machine weight, large parts, generally by spraying for coating. Spraying tools are air spray guns, high-pressure airless spray guns, air-assisted spray guns and hand-held electrostectrective spray guns. Air spray gun spraying efficiency is low (about 30%,) high-pressure airless spray gun waste paint, the two common features are more serious environmental pollution, so has been and is being replaced by air-assisted spray gun and hand-held electrostectrective spray gun. Small and medium-sized components can also be used water curtain paint room or no pump paint room, the former has advanced performance, the latter is affordable, convenient and practical. Because the whole machine and parts of the construction machinery is heavy and the heat capacity is large, the drying of its anti-rust coating generally uses the drying method of the hot air flow with even baking. Heat sources can be selected from steam, electricity, light diesel, natural gas and liquefied petroleum gas.