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1. How is the polymerization heat curing considered in the engineering quota for anti-corrosion coatings, and what if other methods are used? How should it be handled? Quota-based aggregate thermosetting involves indirect polymerization and curing using steam and infrared radiation; if other methods are used, calculations must be carried out separately according to the construction plan. 2. Does the quota for anti-corrosion coating projects include rust removal work? The quota for anti-corrosion coating projects does not include rust removal work. 3. What is the coating mixture ratio? What should be done to calculate the labor and machinery costs when the coating mixture ratio differs from the actual design ratio? A coating mixture consists mainly of four components: (1) film-forming substances, such as various resins, vegetable oils, asphalt, etc. (2) Pigments, such as the white pigment titanium dioxide, the black pigment carbon black, and the colored pigment benzidine yellow, etc. (3) Solvents, such as chlorinated hydrocarbons and nitrohydrocarbons, esters, benzene-based solvents, terpene solvents, etc. (4) Various additives, such as silicone resin leveling agents. By mixing these components in a certain ratio (usually by weight), the desired coating can be obtained. The ratio used to prepare the coating is the coating mix ratio. When the coating mix ratio differs from the actual designed mix ratio, it can be adjusted according to the design requirements, while the amounts of labor and machinery required remain unchanged. 4. Which types of construction projects are covered by the quotas for anti-corrosion coating work? These quotas apply to various anti-corrosion coatings used on equipment, pipelines, metal structures, etc. 5. What is polymerization? What are the common methods of polymerization? Polymerization is the process of converting the organic impregnant that has penetrated the pores of concrete into a solid polymer. Polymerization methods include: (1) Radiation method: high-energy radiation polymerization without the use of an initiator. (2) Heating method: Heat-induced polymerization with an initiator. 6. What is the chemical method? What is thermal curing? The chemical method refers to pure chemical polymerization that requires no radiation or heating, only initiators and accelerators. The function of paint is to form a tough solid film on the surface of a material. Generally, paint is initially a liquid that turns into a solid film after application; this is a process in which the glass transition temperature gradually increases, and this process is what constitutes the formation of a solid. The process of forming a film by heat melting is thermal curing. 7. In the quotas for anti-corrosion coating projects, if new types of coatings that are not included in these quotas are used, how should the quotas be applied? In such cases, the relevant quota items should be used, with no changes to the labor and machinery requirements. 8. What is perchloroethylene paint? How is it taken into account in the pricing standards for anti-corrosion coatings? Perchloroethylene paint is formulated from perchloroethylene resin, plasticizers, heat stabilizers, drying oils, or other modified resins, as well as solvents. The specified perchloroethylene coatings in this chapter are based on the spraying application method. 9. Does the corrosion-resistant coating project include heat curing? The quota for corrosion-resistant coating projects does not cover heat curing; it should be calculated separately according to the relevant quotas. 10. What is paint? What is its basic designation? Paint is a substance that is applied to the surface of objects to give them an attractive appearance or to protect them from degradation; examples include paints and drying oils. 11. In anti-corrosion coating projects, other coatings are considered for application by brushing; but when spraying is used, how should the labor and materials costs be calculated? All other coatings are assumed to be applied by brushing. In the case of spraying work, labor is multiplied by a factor of 0.3, materials are multiplied by a factor of 1.16, and costs related to spraying machinery are added. 12. What are the rules for calculating the quantity of work for the acid-resistant anti-corrosion coating finish layer? (1) The quantity of work for acid-resistant anti-corrosion coating projects should be calculated by distinguishing between different types of such coatings as well as the number of application layers, based on the actual area covered, measured in “m2”. The areas occupied by structures and equipment foundations that protrude above the ground surface should be deducted from this figure. protruding parts from the wall surface, such as brick stacks, are calculated based on their exposed area and included in the scope of work for wall anti-corrosion treatment. (2) The final quantity for the acid-resistant anti-corrosion coating finish layer (the quantity used in quota calculation) is calculated in square meters by multiplying the calculated quantity by the corresponding coefficient specified in the \"Decoration Works\" section. 13. What is corrosion? Into how many categories is corrosion prevention engineering divided? During the production process, various building materials suffer physical and chemical damage to varying degrees due to the action of substances such as acids, bases, salts, and organic solvents; this phenomenon is commonly referred to as corrosion. Currently, the common types of anti-corrosion works in construction projects are as follows: (1) Sodium silicate-based anti-corrosion works. (2) Sulfur-based corrosion prevention projects. (3) Asphalt-based anti-corrosion projects. (4) Resin-based anti-corrosion engineering. (5) Corrosion protection works for blocks. (6) PVC anti-corrosion project. (7) Coating anti-corrosion project. 14. What is anti-corrosion paint? Where is it suitable for use? The paint used in anti-corrosion projects is formulated by combining film-forming substances (oils, resins) with fillers, pigments, tougheners, organic agents, etc., in certain proportions. It is mainly suitable for areas subject to chemical atmospheric corrosion, acid mist corrosion, and splashes of corrosive liquids. Common corrosion-resistant coatings include polyethylene oxide paint, asphalt paint, raw lacquer, cresol resin, phenolic paint, polyurethane paint, and other related types. 15. How to calculate the quantity of work for spraying paint on walls, columns, beams, and ceilings? The quantity of work for spraying paint on walls, columns, beams, and ceilings is calculated based on the area that is to be sprayed. The quantities for different flower dot sizes, as well as those for planar or vertical views, should be calculated separately. 16. What are the principles for selecting coatings? The main principles for choosing coatings are: (1) the material of the object. Applying the same coating to different materials yields different results; therefore, the material of the object is a very important factor in determining how well the coating will appear. On surfaces such as concrete, oil-based paints cannot be used, as they undergo a saponification reaction with the alkaline substances in concrete, causing the coating to peel off. (2) The compatibility of coatings refers mainly to whether there are any reactions between the primer, putty, topcoat, and sealant, as well as the degree of adhesion. If these materials react with each other or the adhesion is insufficient, the paint film will delaminate and peel off. (3) Scope of application and environmental conditions of the coating. The scope of application of coatings is very important; different types of coatings should be used depending on the properties of the coating layer required for various materials. For example, painting the outer surfaces of steel pipes, equipment, and steel structures is primarily done to prevent corrosion and ensure durability, which is why anti-rust paint is generally used. 17. What are epoxy resin paints and phenolic resin paints? Epoxy resin paints (available in both dried-type and air-dry type) are made by grinding epoxy resin, solvents, fillers, plasticizers, and pigments together; when an amine curing agent is added, they become air-dry type. It has strong alkali resistance, as well as resistance to organic solvents, moisture and cold, and wear; however, it is not resistant to corrosion by benzene, propylene, ethanol, ***, nitric acid, sulfuric acid, etc. Toxic; caution is required during construction. Phenolic resin paints are primarily made from phenolic resins, with various other materials added during formulation. They come in two types: varnishes and enamels. These paints can resist corrosion caused by acids, alkalis, and salts; they also exhibit some resistance to dilute acids and can withstand acidic gases. However, they are not resistant to concentrated phosphoric acid or nitric acid. Suitable for applying to steel surfaces. 18. How to calculate the quantity of paint applied to walls, columns, and ceilings? The quantity of paint used for walls, columns, and ceilings is calculated based on the total area to be painted. The quantities for different types of coatings, the number of application coats, and the surfaces to be coated should be calculated separately.