A prismatic fin with anti-corrosion coating

Abstract

The present invention relates to a fin with a prismatic surface and an anti-corrosion coating, comprising a substrate with an anti-corrosion coating, a plurality of tube holes being opened on the substrate, and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges being punched out around the periphery of the tube holes on the substrate, wherein the anti-corrosion coating is a phenolic coating formed by spraying a phenolic coating. The fin with a prismatic surface and an anti-corrosion coating of the present invention has a plurality of tube holes opened on the substrate, and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges being punched out around the periphery of the tube holes on the substrate, thereby effectively destroying the "boundary layer" generated when the fluid flows along the surface of the fin during use, thereby strengthening the disturbance of the fluid and effectively preventing the deposition of solid dust in the fluid. The surface anti-corrosion coating can resist corrosion well in an environment with high temperature and corrosive media, and is suitable for an environment with complex media components, high temperature and corrosiveness, such as a gas heat exchanger for a waste-to-energy gas-fired unit.

Description

Technical Field

[0001] The invention relates to the technical field of heat exchangers for garbage power generation gas turbines, and in particular to a prismatic fin with an anti-corrosion coating used in a gas turbine heat exchanger. Background Art

[0002] Using fins with an anti-corrosion coating is one of the most effective ways to improve the gas-side corrosion resistance of heat exchangers. Conventional fins are coated with a corrosion-resistant metal layer, known as coated fins. Experimental studies have shown that when using coated fins, the coating on the fins can easily blow off during high-temperature flow, especially when the fluid contains corrosive components such as water and hydrogen sulfide. This can cause corrosion on the fins, block the gas-side passage, increase gas-side resistance, and affect heat transfer efficiency.

[0003] In summary, the art lacks a prismatic fin with an anti-corrosion coating that can solve the above-mentioned technical problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a fin with a prismatic surface and an anti-corrosion coating in order to solve the above-mentioned problems.

[0005] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is as follows:

[0006] A fin with an anti-corrosion coating on a prismatic surface comprises a base plate with an anti-corrosion coating, a plurality of tube holes are opened on the base plate, and projections with the anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes on the base plate. The anti-corrosion coating is a phenolic coating, which is formed by spraying a phenolic paint.

[0007] Preferably, the height of the protrusion on the substrate is 0.8 mm, the length of the long diagonal of the rhombus is 4-7 mm, and the length of the short diagonal is 2-5 mm; and the thickness of the phenolic coating is 7-9 μm.

[0008] Preferably, the phenolic coating consists of phenolic epoxy resin, n-butyl methacrylate, silane coupling agent, terephthalate, polydimethylsiloxane, aqueous zinc phosphate, octadecyltrimethylammonium chloride, colloidal graphite, cosolvent and diluent.

[0009] Preferably, the phenolic coating is composed of the following raw materials in parts by weight: 60-70wt% of phenolic epoxy resin, 10-15wt% of n-butyl methacrylate, 5-10wt% of silane coupling agent, 1-3wt% of terephthalate, 2-4wt% of polydimethylsiloxane, 1-3wt% of aqueous zinc phosphate, 4-8wt% of octadecyltrimethylammonium chloride, 1-3wt% of colloidal graphite, 2-5wt% of cosolvent and 10-15wt% of diluent.

[0010] Preferably, the phenolic coating is composed of the following raw materials in parts by weight: 60wt% of phenolic epoxy resin, 10wt% of n-butyl methacrylate, 5wt% of silane coupling agent, 2wt% of terephthalate, 2wt% of polydimethylsiloxane, 1wt% of aqueous zinc phosphate, 5wt% of octadecyltrimethylammonium chloride, 1wt% of colloidal graphite, 2wt% of cosolvent and 10wt% of diluent.

[0011] Preferably, the phenolic coating is composed of the following raw materials in parts by weight: 65wt% of phenolic epoxy resin, 12wt% of n-butyl methacrylate, 8wt% of silane coupling agent, 1wt% of terephthalate, 3wt% of polydimethylsiloxane, 2wt% of aqueous zinc phosphate, 6wt% of octadecyltrimethylammonium chloride, 2wt% of colloidal graphite, 4wt% of cosolvent and 8wt% of diluent.

[0012] Preferably, the phenolic coating is composed of the following raw materials in parts by weight: 70wt% of phenolic epoxy resin, 15wt% of n-butyl methacrylate, 5wt% of silane coupling agent, 1wt% of terephthalate, 2wt% of polydimethylsiloxane, 1wt% of aqueous zinc phosphate, 8wt% of octadecyltrimethylammonium chloride, 3wt% of colloidal graphite, 5wt% of cosolvent and 15wt% of diluent.

[0013] Preferably, the cosolvent is any two or more of ethanol, sodium benzoate, polyethylene glycol and isophorone.

[0014] Preferably, the diluent is any one or more of propylene glycol methyl ether acetate, butanol or cyclohexanone.

[0015] Preferably, the preparation method of the phenolic coating comprises the following steps:

[0016] (1) adding phenolic epoxy resin, n-butyl methacrylate, silane coupling agent, terephthalate, polydimethylsiloxane, aqueous zinc phosphate, colloidal graphite, a cosolvent and 1 / 2 of the diluent according to the formula ratio into a reaction kettle, stirring and dispersing them, and then sand-milling them to a fineness of less than 30 μm with a sand mill. Then, heating the mixture to 8° C. and keeping it warm for 30 minutes, and then cooling it to 40° C. to prepare a slurry;

[0017] (2) Then add octadecyltrimethylammonium chloride to the slurry, stir and disperse, and finally add 1 / 2 of the formula amount of diluent and stir evenly. When the solid content reaches 40-50%, filter and obtain the phenolic coating.

[0018] The beneficial effects of the present invention are:

[0019] 1. The fins with phenolic anti-corrosion coatings on the prismatic surfaces of the present invention are formed by punching a number of tube holes on a substrate and forming horizontal and vertical ridge-shaped projections with anti-corrosion coatings around the perimeter of the tube holes. This effectively destroys the "boundary layer" generated by fluid flow along the surface of the fins during use, enhancing fluid disturbance and effectively preventing the deposition of solid dust in the fluid. Furthermore, the size of the projections is strictly controlled to maximize the diffusion area and improve heat exchange efficiency. The surface anti-corrosion coating can effectively resist corrosion in high-temperature, corrosive media environments and is suitable for environments with complex media components, high temperatures, and corrosive environments, such as gas heat exchangers for waste-to-energy gas turbines.

[0020] 2. The phenolic coating of the present invention combines the excellent chemical resistance of phenolic epoxy resin with the heat resistance, acid and alkali resistance, high temperature resistance and high humidity resistance of components such as n-butyl methacrylate, silane coupling agent, terephthalate, water-based zinc phosphate and colloidal graphite. In addition, polydimethylsiloxane and cosolvent are added to enhance the corrosion resistance of the coating, improve the adhesion and flexibility of the paint film, and improve the construction performance of the coating, so that the coating can adapt to various harsh corrosive environments; colloidal graphite has special oxidation resistance, self-lubrication and plasticity under high temperature conditions, which improves the thermal conductivity and adhesion of the paint layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a front view of a prismatic fin with an anti-corrosion coating according to the present invention;

[0023] Figure 2 It is a left view of a prismatic fin with an anti-corrosion coating according to the present invention.

[0024] In the figure: 1—fin, 2—tube hole. DETAILED DESCRIPTION

[0025] Example 1

[0026] See also Figure 1-2The present invention provides a fin with an anti-corrosion coating on a prismatic surface, comprising a substrate 1 with an anti-corrosion coating, wherein the substrate 1 is provided with a plurality of tube holes 2, and protrusions with an anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes 2 on the substrate. The anti-corrosion coating is a phenolic coating, which is sprayed with a phenolic paint. The height of the peaks or troughs of the horizontal and vertical diamond shapes on the substrate 1 is 0.8 mm, and the widths of the two sides of the diamond shape are 5.33 mm and 4 mm respectively. The thickness of the phenolic coating is 7-9 μm.

[0027] The phenolic coating is composed of the following raw materials in parts by weight: 60 wt% of phenolic epoxy resin, 10 wt% of n-butyl methacrylate, 5 wt% of silane coupling agent, 2 wt% of terephthalate, 2 wt% of polydimethylsiloxane, 1 wt% of aqueous zinc phosphate, 5 wt% of octadecyltrimethylammonium chloride, 1 wt% of colloidal graphite, 2 wt% of cosolvent and 10 wt% of diluent.

[0028] The cosolvent is a mixture of ethanol and sodium benzoate, and the mass ratio of ethanol to sodium benzoate is 1:1.5.

[0029] The diluent is a mixture of propylene glycol methyl ether acetate and butanol, and the mass ratio of propylene glycol methyl ether acetate to butanol is 2:1.

[0030] The preparation method of phenolic coating comprises the following steps:

[0031] (1) Add phenolic epoxy resin, n-butyl methacrylate, silane coupling agent, terephthalate, polydimethylsiloxane, aqueous zinc phosphate, colloidal graphite, cosolvent and 1 / 2 of the formula amount of diluent into a reaction kettle according to the formula ratio, first stir and disperse, then sand grind with a sand mill to a fineness of less than 30 μm, then heat the mixture to 8° C. and keep it warm for 30 minutes, then cool it to 40° C. to prepare a slurry; (2) then add octadecyltrimethylammonium chloride into the slurry, stir and disperse, finally add 1 / 2 of the formula amount of diluent and stir evenly, detect when the solid content reaches 40-50%, filter, and obtain a phenolic coating.

[0032] Example 2

[0033] See also Figure 1-2 The present invention provides a fin with an anti-corrosion coating on a prismatic surface, comprising a substrate 1 with an anti-corrosion coating, wherein the substrate 1 is provided with a plurality of tube holes 2, and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes 2 on the substrate. The anti-corrosion coating is a phenolic coating, which is sprayed with a phenolic paint. The height of the peaks or troughs of the horizontal and vertical diamond shapes on the substrate 1 is 0.8 mm, the widths of the two sides of the diamond shape are 5.33 mm and 4 mm respectively, and the thickness of the phenolic coating is 7-9 μm.

[0034] The phenolic coating is composed of the following raw materials in parts by weight: 65wt% of phenolic epoxy resin, 12wt% of n-butyl methacrylate, 8wt% of silane coupling agent, 1wt% of terephthalate, 3wt% of polydimethylsiloxane, 2wt% of aqueous zinc phosphate, 6wt% of octadecyltrimethylammonium chloride, 2wt% of colloidal graphite, 4wt% of cosolvent and 8wt% of diluent.

[0035] The cosolvent is a mixture of ethanol, sodium benzoate and polyethylene glycol, and the mass ratio of ethanol, sodium benzoate and polyethylene glycol is 1:1.5:1.

[0036] The diluent is propylene glycol methyl ether acetate.

[0037] The preparation method of the phenolic coating is the same as that in Example 1.

[0038] Example 3

[0039] See Figure 1-2 The present invention provides a fin with an anti-corrosion coating on a prismatic surface, comprising a substrate 1 with an anti-corrosion coating, wherein the substrate 1 is provided with a plurality of tube holes 2, and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes 2 on the substrate. The anti-corrosion coating is a phenolic coating, which is sprayed with a phenolic paint. The height of the peaks or troughs of the horizontal and vertical diamond shapes on the substrate 1 is 0.8 mm, the widths of the two sides of the diamond shape are 5.33 mm and 4 mm respectively, and the thickness of the phenolic coating is 7-9 μm.

[0040] The phenolic coating is composed of the following raw materials in parts by weight: 70wt% of phenolic epoxy resin, 15wt% of n-butyl methacrylate, 5wt% of silane coupling agent, 1wt% of terephthalate, 2wt% of polydimethylsiloxane, 1wt% of aqueous zinc phosphate, 8wt% of octadecyltrimethylammonium chloride, 3wt% of colloidal graphite, 5wt% of cosolvent and 15wt% of diluent.

[0041] The cosolvent is a mixture of ethanol, polyethylene glycol and isophorone, and the mass ratio of ethanol, polyethylene glycol and isophorone is 1::2:1.

[0042] The diluent is a mixture of butanol or cyclohexanone, and the mass ratio of butanol to cyclohexanone is 1:1.

[0043] The preparation method of the phenolic coating is the same as that in Example 1.

[0044] Example 4

[0045] See also Figure 1-2The present invention provides a fin with an anti-corrosion coating on a prismatic surface, comprising a substrate 1 with an anti-corrosion coating, wherein the substrate 1 is provided with a plurality of tube holes 2, and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes 2 on the substrate. The anti-corrosion coating is a phenolic coating, which is sprayed with a phenolic paint. The height of the peaks or troughs of the horizontal and vertical diamond shapes on the substrate 1 is 0.8 mm, the widths of the two sides of the diamond shape are 5.33 mm and 4 mm respectively, and the thickness of the phenolic coating is 7-9 μm.

[0046] 60-70wt% of phenolic epoxy resin, 12wt% of n-butyl methacrylate, 7wt% of silane coupling agent, 2wt% of terephthalate, 3wt% of polydimethylsiloxane, 2wt% of aqueous zinc phosphate, 5wt% of octadecyltrimethylammonium chloride, 1.5wt% of colloidal graphite, 3wt% of cosolvent and 14wt% of diluent.

[0047] The cosolvent is a mixture of ethanol and sodium benzoate, and the mass ratio of ethanol to sodium benzoate is 3:1.

[0048] The diluent is a mixture of propylene glycol methyl ether acetate, butanol and cyclohexanone, and the mass ratio of propylene glycol methyl ether acetate, butanol and cyclohexanone is 2:1:1.

[0049] The preparation method of the phenolic coating is the same as that in Example 1.

[0050] Example 5 Material Performance Test

[0051] Comparative Example 1 uses a phenolic resin coating produced by Dongguan Heyue Coating Technology Co., Ltd., and Comparative Example 2 uses a fluorocarbon coating produced by Shanghai Masda Industrial Co., Ltd. Both are sprayed on the test workpiece, sprayed for the same time, and the test workpieces are of the same size. The adhesion test is carried out in accordance with the standard ASTM D3359, and the adhesion is divided into 6 quality levels from 0 to 5, with level 5 being the best. The salt spray corrosion performance verification GB / T6461-2002 was tested; the test results are shown in Table 1.

[0052] Table 1 Performance test results

[0053]

[0054]

[0055] The foregoing descriptions of specific exemplary embodiments of the present invention are for purposes of illustration and description. These descriptions are not intended to limit the invention to the precise forms disclosed, and it is apparent that many variations and modifications are possible in light of the foregoing teachings. The exemplary embodiments have been selected and described for the purpose of explaining the specific principles of the invention and their practical application, thereby enabling those skilled in the art to realize and utilize a variety of exemplary embodiments of the invention and various options and modifications. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A prismatic fin with an anti-corrosion coating, characterized in that: The invention comprises a substrate (1) with an anti-corrosion coating, wherein a plurality of tube holes (2) are formed on the substrate (1), and protrusions with the anti-corrosion coating in the shape of horizontal and vertical ridges are punched around the tube holes (2) on the substrate (1), wherein the anti-corrosion coating is a phenolic coating formed by spraying a phenolic paint; The height of the protrusion on the substrate (1) is 0.8 mm, the length of the long diagonal of the rhombus is 4-7 mm, and the length of the short diagonal is 2-5 mm; the thickness of the phenolic coating is 7-9 μm; The phenolic coating is composed of the following raw materials in parts by weight: 60-70 wt% of phenolic epoxy resin, 10-15 wt% of n-butyl methacrylate, 5-10 wt% of silane coupling agent, 1-3 wt% of terephthalate, 2-4 wt% of polydimethylsiloxane, 1-3 wt% of aqueous zinc phosphate, 4-8 wt% of octadecyltrimethylammonium chloride, 1-3 wt% of colloidal graphite, 2-5 wt% of cosolvent and 10-15 wt% of diluent.

2. The prismatic fin with anti-corrosion coating according to claim 1, characterized in that: The phenolic coating is composed of the following raw materials in parts by weight: 60 wt% of phenolic epoxy resin, 10 wt% of n-butyl methacrylate, 5 wt% of silane coupling agent, 2 wt% of terephthalate, 2 wt% of polydimethylsiloxane, 1 wt% of aqueous zinc phosphate, 5 wt% of octadecyltrimethylammonium chloride, 1 wt% of colloidal graphite, 2 wt% of cosolvent and 10 wt% of diluent.

3. The prismatic fin with anti-corrosion coating according to claim 1, characterized in that: The cosolvent is any two or more of ethanol, sodium benzoate, polyethylene glycol and isophorone.

4. The prismatic fin with anti-corrosion coating according to claim 1, characterized in that: The diluent is any one or more of propylene glycol methyl ether acetate, butanol or cyclohexanone.

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