CN110628244B - High-temperature energy-saving anticorrosive paint for metal baffle of sintering trolley and application thereof - Google Patents

High-temperature energy-saving anticorrosive paint for metal baffle of sintering trolley and application thereof Download PDF

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CN110628244B
CN110628244B CN201810654787.1A CN201810654787A CN110628244B CN 110628244 B CN110628244 B CN 110628244B CN 201810654787 A CN201810654787 A CN 201810654787A CN 110628244 B CN110628244 B CN 110628244B
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sintering trolley
metal
coating
baffle plate
metal baffle
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CN110628244A (en
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甘菲芳
李咸伟
毛晓明
向家发
胡子国
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Baoshan Iron and Steel Co Ltd
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Baoshan Iron and Steel Co Ltd
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    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D1/00Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/08Anti-corrosive paints
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D5/00Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
    • C09D5/18Fireproof paints including high temperature resistant paints
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40Additives
    • C09D7/60Additives non-macromolecular
    • C09D7/61Additives non-macromolecular inorganic
    • CCHEMISTRY; METALLURGY
    • C09DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09DCOATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
    • C09D7/00Features of coating compositions, not provided for in group C09D5/00; Processes for incorporating ingredients in coating compositions
    • C09D7/40Additives
    • C09D7/65Additives macromolecular

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
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Abstract

The invention relates to a high-temperature energy-saving anticorrosive paint for a metal baffle of a sintering trolley and an application method thereof. The coating comprises 15-35 parts by weight of zircon powder, 3-10 parts by weight of silicon carbide powder, 39-43 parts by weight of mullite powder, 3-10 parts by weight of ball clay, 2-7 parts by weight of spodumene, 2-5 parts by weight of metal silicon and 5-15 parts by weight of aluminum magnesium silicate gel powder. When in use, water is added to prepare fine slurry, the fine slurry is sprayed or smeared on the metal surface of the baffle plate, and the coating is firmly adhered to the metal surface of the baffle plate after drying and heat treatment to form the high-temperature-resistant energy-saving anticorrosive ceramic coating. The baffle plate can reflect the heat of a material layer, reduce the temperature of the inner wall of the baffle plate and prevent corrosion to protect the inner wall surface of the metal baffle plate. Therefore, the service life of the baffle plate can be prolonged, and meanwhile, the energy-saving effect is achieved, and the production cost of the sinter is reduced.

Description

High-temperature energy-saving anticorrosive paint for metal baffle of sintering trolley and application thereof
Technical Field
The invention belongs to the technical field of inorganic materials, particularly belongs to the field of anticorrosive coatings, and particularly relates to a high-temperature energy-saving anticorrosive coating for a baffle of a sintering trolley.
Background
The most widely used sintering equipment in iron works is the belt sintering machine, and the sintering pallet consists of a pallet body, a baffle plate, a heat insulation pad, a grate bar, wheels and the like. The baffle of the trolley of the strand sintering machine is one of the main wearing parts. The baffle is generally cast by ferrite ductile iron, and due to the fact that the baffle works under the conditions of high temperature and chilling and heating, the baffle is easy to deform and crack, and the service life of the baffle is generally shortened by 3-6 months. Therefore, the improvement of the service life of the baffle is one of the problems to be solved urgently in the production of the sintering machine trolley. In the sintering process, the inner wall of the baffle is contacted with a glowing sintering material, the temperature of the material layer is about 1000-1100 ℃ at most, and the local highest temperature of the inner wall of the baffle is about 850-950 ℃. The trolley overturns and unloads when running to the tail part of the sintering machine, and the baffle is cooled. Thus, the baffle plate is not uniformly heated or cooled during operation. In the process of continuous heating and cooling circulation, the baffle is acted by alternating stress to form micro-cracks, and the micro-cracks gradually expand to form through cracks so as to break the baffle. Meanwhile, due to the cyclic utilization of the dedusting ash in the sinter, a large amount of harmful elements such as K, Na, Pb, Zn and the like are enriched, and the harmful elements aggravate the corrosion to the metal baffle and also cause the service life of the baffle to be reduced. If the ceramic coating is coated on the inner wall of the metal baffle, the heat of a material layer can be reflected, the temperature of the inner wall of the baffle is reduced, and meanwhile, the ceramic coating is also anti-corrosive and protects the inner wall surface of the metal baffle. Therefore, the service life of the baffle plate can be prolonged, energy is saved, and the production cost of the sinter is reduced.
Through consulting the published documents, the high-temperature infrared radiation energy-saving coating has wide application, can improve the heat efficiency and the heating quality of products in an industrial kiln, and has good protection effect on base materials. Because the application places are different from the working conditions, the energy-saving coatings have various characteristics. For example, patent application CN 101875566A "a high-temperature energy-saving coating for ceramics" mainly comprises potash feldspar, bentonite, brown corundum, SiC, clay, quartz and ZrO2BeO, propanol, etc. in certain proportion. Has quite high radiance in a very high temperature range, has good thermal stability, is used on the ceramic heating surface, and has obvious energy-saving effect.
The patent application CN 1583889A "a high-temperature resistant energy-saving coating for metal" adopts silica sol, alumina sol and aluminium dihydrogen phosphate as binding agents, and uses modified silicon carbide as powder to prepare the high-temperature resistant energy-saving coating for metal, which is used on the surfaces of stainless steel, heat-resistant steel and common carbon steel, is not oxidized and decomposed under the action of high-temperature heat load, has high radiance and good thermal stability, and is a good high-temperature resistant energy-saving coating for metal. Can protect the metal matrix from high-temperature corrosion, strengthen the radiation absorption thermal property and have obvious energy-saving effect.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a high-temperature energy-saving anticorrosive coating for a metal baffle plate of a sintering trolley, which is particularly suitable for the working conditions of sintering trolleys, has the characteristics of good thermal shock, good high temperature resistance, high radiance, good corrosion resistance and convenient construction, can prolong the service life of the baffle plate of the trolley, and is energy-saving and environment-friendly.
The energy-saving anticorrosive high-temperature coating disclosed by the invention has the advantages that the highest use temperature is ensured to reach 1100 ℃, the coating can bear frequent temperature cold and hot changes, the corrosion of harmful elements such as K, Na and the like is also resisted, and the use conditions are more severe. Therefore, the coating of the invention also needs good high temperature resistance, erosion resistance and oxidation resistance on the basis of energy conservation, and must combine the technical characteristics of high-temperature ceramics and energy-saving coatings.
The high-temperature energy-saving anticorrosive paint for the metal baffle of the sintering trolley comprises the following components in parts by weight:
Figure GDA0002990463590000021
preferably, the particle sizes of the aluminum magnesium silicate gel powder, the zircon powder, the silicon carbide powder, the mullite powder, the ball clay, the spodumene, the metal silicon and the carboxymethyl cellulose are 325-1000 meshes.
The invention also provides a preparation method of the high-temperature energy-saving anticorrosive coating for the metal baffle of the sintering trolley, which is to uniformly mix the components in proportion and put into a stirrer for dry mixing and uniform stirring.
The invention also provides a spraying or brushing method of the sintering trolley metal baffle, which comprises the following steps:
(1) adding 25-35% by mass of water into the high-temperature energy-saving anticorrosive paint for the sintering trolley metal baffle, and uniformly stirring to form a water-based paint;
(2) spraying or coating the water-based paint on the surface of the metal baffle of the sintering trolley, wherein the spraying or coating thickness is 1-2 mm;
(3) and (3) placing the sprayed or coated sintering trolley metal baffle for 8 hours at normal temperature, drying and forming primary strength. For better application effect, the metal baffle of the sintering trolley after being placed for 8 hours idles once along with the sintering trolley, so that the coating is firmly adhered to the technical surface of the baffle at the current temperature of the sintering machine, and a sintered high-strength ceramic coating is also formed. The coating with added water is required to finish painting construction within 4 hours, otherwise, the coating is easy to harden and lose efficacy.
Mullite has excellent thermal shock resistance and good high-temperature volume stability, is Al203-Si02The binary solid solution is only stable at normal pressure in the element system, the hardness is high, and the refractoriness reaches 1800 ℃. The mullite ceramic has the characteristics of uniform expansion, excellent thermal shock stability, good chemical corrosion resistance and the like. Mullite powder Al2O3≥68%。
The zircon has high refractoriness and good thermal shock resistance, and is used as radiation powder in the coating. Zircon powder ZrO2≥60%。
The silicon carbide has high refractoriness and good wear resistance, and is used as radiation powder in the coating. The SiC powder is more than or equal to 96 percent. However, it is not versatile because of its poor oxidation resistance.
The ball clay is a clay mineral containing microcrystalline kaolinite and alpha-quartz particles as main mineral components, and is used for enhancing the suspension property of a coating after water is added into the coating so that formed slurry is not segregated. Preferably, Al in ball clay2O3Greater than or equal to 28 percent and plasticity index greater than or equal to 24 percent.
The spodumene has small expansion and good thermal shock performance, and is also used as a ceramic sintering agent in the coating.
The carboxymethyl cellulose is used for leading the coating to have better suspension property, water retention property, water reducing property and construction smearing property.
The aluminum magnesium silicate gel powder is a fine hydraulic inorganic cementing material with a powder granularity D500.1 to 2 μm, and SiO as a main component2 60~66%,Al2O316-22% and MgO 2-4%. After water is added, the plastic slurry can be hardened in air and water. The silicon-aluminum-magnesium material can form a slurry body after water is added. The adhesive cement has high bonding capacity, can bond framework materials, filling materials, high molecular polymers and other materials together, and gradually coagulates and hardens to obtain strength and durability.
The metallic silicon can be chemically reacted with water vapor and oxygen at 900-1200 DEG CReaction to produce a dense layer of silicon dioxide (SiO)2) And the film protects the metal surface of the baffle. Meanwhile, the Si strengthens the thermochemical reaction between the coating and the substrate and the penetration of elements, and increases the binding force between the coating and the metal substrate; the metal Si is also a good antioxidant, protects SiC in the coating and plays a stable radiation energy-saving effect.
Thus, the chemical component of the coating formed by the components is ZrO2、Al2O3、SiO2、MgO、SiC,Li2And the inorganic ceramic material system of O ensures the high temperature resistance, thermal shock resistance, high radiance and corrosion resistance of the coating.
Preferably, the granularity of each component in the high-temperature energy-saving anticorrosive paint for the sintering trolley metal baffle is controlled between 325 meshes and 1000 meshes. The coating is made of ceramic powder with good thermal shock resistance, high temperature resistance and corrosion resistance; reflecting agent components SiC and ZrO2、SiO2、Al2O3Under different temperatures and wavelengths, the emissivity of the MgO has complementarity; the added metal has the function of oxidation resistance and increases the bonding strength of the coating. The components have different functions, so that the coating has good comprehensive performance and stable application effect.
The technology not only prolongs the service life of the baffle plate of the sintering trolley, but also can realize that the whole sintering trolley is more energy-saving, reduce the consumption of sintering energy, improve the field operation environment and generate more comprehensive benefits.
Detailed Description
The raw materials are prepared according to the following table 1:
TABLE 1 coating compositions of examples 1-3
Figure GDA0002990463590000041
The components are taken according to the examples 1-3 in the table 1 and are uniformly mixed, and the mixture is placed into a stirrer to be dry-mixed and uniformly stirred, so that the high-temperature energy-saving anticorrosive paint for the metal baffle plate of the sintering trolley disclosed by the examples 1-3 in the invention is obtained. Before using, proper amount of clean water in Table 1 is added into the coating before construction, and the water-based coating is obtained by stirring the mixture evenly again. And (3) coating the water-based paint on the metal surface of the baffle plate of the sintering trolley, wherein the coating thickness is 1-2 mm, and the water-based paint is coated in 2-3 times. The coated baffle was allowed to dry at room temperature for 8 hours and developed a green strength. Then, the coating is firmly adhered to the technical surface of the baffle at the existing temperature (1000 ℃) of the sintering trolley along with the idling of the sintering trolley, and a ceramic coating of the high-temperature radiation anticorrosive coating is formed. The properties of the coatings were tested and the results are shown in table 2.
TABLE 2 technical Properties of examples 1 to 3 of the present technology
Figure GDA0002990463590000042
Figure GDA0002990463590000051
1) And (3) oxidation resistance detection: the coating of the invention is coated on the surface of a baffle metal block with the thickness of 40mm multiplied by 160mm, the baffle metal block is put into an electric furnace after being dried and is subjected to heat treatment at the temperature of 1000 ℃ multiplied by 24h, the baffle metal block is taken out after natural cooling, and the color and the integrity of the coating surface are observed. The coating did not whiten indicating good oxidation resistance.
2) And (3) corrosion resistance detection: and collecting the accretions on the sintering trolley, placing the accretions on the surface of the metal plate with the existing coating, performing heat treatment at 1000 ℃ for 24 hours, and observing the corrosion condition of the surface of the metal plate.
3) The surface of the metal plate with the coating is placed in an electric furnace at 1000 ℃ for heating for 10min, the metal plate is taken out and placed in air for cooling for 10min, the circulation is carried out for 1 time, the bonding property of the coating and the metal plate and the integrity of the coating are observed after 10 times of circulation, and the thermal shock resistance test result is determined.
4) And detecting and analyzing the normal phase total emissivity according to the GB7286.1 standard.

Claims (5)

1. The high-temperature energy-saving anticorrosive paint for the metal baffle of the sintering trolley is characterized by comprising the following components in parts by weight:
Figure FDA0002990463580000011
2. the high-temperature energy-saving anticorrosive paint for the metal baffle plate of the sintering trolley as claimed in claim 1, which is characterized in that: the particle sizes of the aluminum magnesium silicate gel powder, the zircon powder, the silicon carbide powder, the mullite powder, the ball clay, the spodumene, the metal silicon and the carboxymethyl cellulose are 325-1000 meshes.
3. The preparation method of the high-temperature energy-saving anticorrosive paint for the metal baffle plate of the sintering trolley as claimed in claim 1 or 2, comprising the following steps: the components as described in claim 1 or 2 are mixed evenly according to the proportion and put into a stirrer for dry mixing and even stirring.
4. A spraying or brushing method for a metal baffle of a sintering trolley is characterized by comprising the following steps:
(1) adding 25-35% by mass of water into the high-temperature energy-saving anticorrosive paint for the metal baffle plate of the sintering trolley according to claim 1 or 2, and uniformly stirring to form a water-based paint;
(2) spraying or coating the water-based paint on the surface of the metal baffle of the sintering trolley, wherein the spraying or coating thickness is 1-2 mm;
(3) and (3) placing the sprayed or coated sintering trolley metal baffle for 8 hours at normal temperature, drying and forming primary strength.
5. The spraying or painting method according to claim 4, characterized in that: the metal baffle of the sintering trolley after being placed for 8 hours idles once along with the sintering trolley.
CN201810654787.1A 2018-06-22 2018-06-22 High-temperature energy-saving anticorrosive paint for metal baffle of sintering trolley and application thereof Active CN110628244B (en)

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