Planar powder coating for ventilating slot plate of wind driven generator and preparation method of planar powder coating

Abstract

The invention discloses a planar powder coating for a ventilating slot plate of a wind driven generator. The planar powder coating is prepared from the following raw materials in parts by mass: 550-600 parts of epoxy resin, 23-25 parts of a curing agent, 1-2 parts of a catalyst, 8-12 parts of a flatting agent, 3-8 parts of a sensitizer, 2-4 parts of a degassing agent, 5-10 parts of a high-temperature-resistant aid, 200-400 parts of high-temperature-resistant pigment and the balance of filler. The invention also discloses a preparation method of the planar powder coating, which comprises the following steps: S1, firstly adding 1 / 2 of epoxy resin, then adding other raw materials, finally adding the other 1 / 2 of epoxy resin, and uniformly stirring; s2, the stirred mixed raw materials are put into an extruder, crushing, roller pressing and screw extrusion are conducted in sequence, the rotating speed frequency of a screw is 40-45 Hz, and the rotating speed frequency of a feeding screw is 20-25 Hz; s3, the powder is sieved through a 200-220-mesh rotary sieve, the particle size D50 is 30-35 micrometers, and 0.05-0.1% of powder flowing drying agent is evenly mixed in the powder grinding process. According to the planar powder coating and the preparation method thereof, the planar powder coating can resist 300 DEG C * 8 hours, and the technical requirements of a ventilation slot plate of a wind driven generator are met.

Description

Technical Field

[0001] The invention relates to the technical field of flat powder coatings, in particular to a flat powder coating for ventilation slot plates of wind turbines and a preparation method thereof. Background Art

[0002] Wind turbine ventilation slots are critical components of wind turbine generator systems, primarily used to optimize air flow within the generator, ensure effective heat dissipation, and prevent overheating. During the production process, wind turbine ventilation slots come into contact with insulating varnish, so the coating must be resistant to immersion in the insulating varnish. After being exposed to 40°C for 24 hours, the coating must be wiped clean with alcohol and show no signs of blistering, peeling, or loss of gloss. Adhesion must be ≤ Level 1 using the 100-grid method. Due to the high ambient temperature of the ventilation slots during use, the coating must be tested at 280°C for 8 hours to show no signs of cracking, blistering, or peeling. Adhesion must be ≤ Level 1 using the 100-grid method. High dimensional accuracy is required during assembly of the ventilation slots, requiring a flat coating with no textured finishes (such as frosted, wrinkled, or lint-like textures).

[0003] The existing wind turbine ventilation slot plate coating has the following problems:

[0004] (1) Since the insulating paint has a strong dissolving or swelling property on the coating on the ventilation slot plate, the general powder coating will dissolve or swell, resulting in blistering, shedding, loss of gloss, etc., and the adhesion will also be reduced or lost.

[0005] (2) Ordinary powder coatings will slowly decompose at 240-250 degrees, resulting in blistering, shedding, etc. Silicone-based powder coatings can withstand high temperatures, but can only produce frosted surfaces, not flat surfaces, and are also more expensive.

[0006] (3) Ordinary powder coatings are not resistant to insulating paint bubbles. Summary of the Invention

[0007] In response to the above technical problems to be solved, the present invention provides a flat powder coating for ventilation slots of wind turbines and a preparation method thereof, which can withstand 300℃*8h and can be made into a flat surface, meeting the technical requirements of ventilation slots of wind turbines.

[0008] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0009] A flat powder coating for ventilation slots of wind turbines is prepared from the following raw materials in parts by mass: 550-600 parts of epoxy resin, 23-25 ​​parts of curing agent, 1-2 parts of catalyst, 8-12 parts of leveling agent, 3-8 parts of brightener, 2-4 parts of degassing agent, 5-10 parts of high-temperature resistant auxiliary agent, 200-400 parts of high-temperature resistant pigment, and the remainder being filler.

[0010] As a further improvement of the above technical solution:

[0011] Preferably, the mass fraction of the raw material is 1000 parts.

[0012] Preferably, the epoxy resin is a two-step bisphenol A epoxy resin.

[0013] Preferably, the curing agent is dicyandiamide.

[0014] Preferably, the catalyst is dimethylimidazole.

[0015] Preferably, the high temperature resistant pigment is one of titanium dioxide, carbon black, iron red and 1039N yellow.

[0016] Preferably, the filler is silicon powder.

[0017] The present invention also discloses a method for preparing a flat powder coating for ventilation slots of a wind turbine generator, which comprises the following steps:

[0018] Step S1, premixing:

[0019] First add 1 / 2 of the epoxy resin, then add other raw materials, and finally add another 1 / 2 of the epoxy resin and stir evenly;

[0020] Step S2, extrusion:

[0021] Put the stirred mixed raw materials into the extruder, crush, press roller, extrusion screw in sequence, the screw speed frequency is 40-45Hz, and the feeding screw speed frequency is 20-25Hz;

[0022] Step S3, grinding:

[0023] After passing through a 200-220 mesh rotary sieve, the particle size D50 is 30-35 microns. During the grinding process, 0.05-0.1% of powder flow desiccant is mixed.

[0024] The flat powder coating for ventilation slots of wind turbines and the preparation method thereof provided by the present invention have the following advantages over the prior art:

[0025] The flat powder coating for wind turbine ventilation slots of the present invention and its preparation method use epoxy resin and dicyandiamide curing agent as a binder to ensure its resistance to immersion in insulating paint; a high-temperature resistant additive is added to ensure its high-temperature resistance. The flat powder coating of the present invention uses silicon micropowder as a filler to ensure that its resistance to immersion in insulating paint and its high-temperature resistance are not reduced. The flat powder coating of the present invention uses a high-temperature resistant inorganic environmentally friendly pigment as a pigment to ensure that its resistance to immersion in insulating paint and its high-temperature resistance are not reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a picture of the test sample of the present invention after spraying. DETAILED DESCRIPTION

[0027] The following is a detailed description of the specific embodiments of the present invention. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0028] The method for preparing a flat powder coating for a ventilation slot plate of a wind turbine generator according to the present invention comprises the following steps:

[0029] Step S1, premixing:

[0030] First add 1 / 2 of the epoxy resin, then add other raw materials, and finally add another 1 / 2 of the epoxy resin into the mixing tank to make mixing more uniform.

[0031] Set the blender to slow stirring for 3 minutes, fast stirring for 60 seconds, and turn on the automatic stirring mode. The speed frequency of slow stirring is 20Hz, and the speed frequency of fast stirring is 40Hz.

[0032] Step S2, extrusion:

[0033] The extruder was preheated to the set temperature. When the machine was turned on, the temperature of each zone was set as follows: Zone I was set to 100°C, Zone II was set to 110°C, and Zone III was set to 100°C.

[0034] Put the stirred mixed raw materials into the feeding hopper of the extruder, and then crush, press roller, and extrusion screw in sequence. The screw speed frequency is adjusted to 40-45Hz, and the feeding screw speed frequency is adjusted to 20-25Hz.

[0035] During the extrusion process, about 100 grams of the middle part of the sheet material was selected, ground with a small grinder, and sieved with 200-250 mesh to make the particle size D50 = 30-35 microns.

[0036] Step S3, grinding:

[0037] Adjust the rotation speed of the main and auxiliary mills, pass through a 200-220 mesh rotary sieve, and the particle size D50 is 30-35 microns. 0.05-0.1% of powder flow desiccant is mixed in the grinding process.

[0038] The following raw materials are used in this embodiment: 550-600 parts of epoxy resin, 23-25 ​​parts of curing agent, 1-2 parts of catalyst, 8-12 parts of GLP588, 3-8 parts of T-701, 2-4 parts of benzoin, 5-10 parts of PTN506E, 200-400 parts of high temperature resistant pigment, and silica powder.

[0039] As described in Table 1, different ratios of raw materials were used for testing.

[0040] Table 1 Raw material ratio

[0041]

[0042]

[0043] The powder coating prepared according to the ratio in Table 1 was sprayed with insulation paint. The product after spraying was as follows: Figure 1 After testing, the light retention rate and color difference of the insulating paint obtained by raw materials with different ratios are shown in Table 2.

[0044] Table 2 Comparison of gloss retention and color difference

[0045]

[0046] Test whether the insulation paint formula is resistant to high temperature:

[0047] The high temperature resistance test method is to place the test plate in a blast drying oven at 280℃ for 8h;

[0048] The index requirement is adhesion level 0 after 280℃*8h test;

[0049] The high temperature resistance test data is: after 300℃*8h, the adhesion is level 0, which is greater than the required index.

[0050] After testing, formula 5 has the best effect.

[0051] The above examples are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, they are not intended to limit the present invention. Therefore, any simple modifications, equivalent variations, and modifications to the above examples that do not depart from the technical solution of the present invention and are based on the technical essence of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A flat powder coating for ventilation slots of wind turbines, characterized in that: The invention is prepared from the following raw materials in parts by mass: 550-600 parts of epoxy resin, 23-25 ​​parts of curing agent, 1-2 parts of catalyst, 8-12 parts of leveling agent, 3-8 parts of brightening agent, 2-4 parts of degassing agent, 5-10 parts of high temperature resistant auxiliary agent, 200-400 parts of high temperature resistant pigment, and the rest are fillers.

2. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The mass fraction of the raw materials is 1000 parts.

3. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The epoxy resin adopts two-step bisphenol A epoxy resin.

4. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The curing agent is dicyandiamide.

5. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The catalyst is dimethylimidazole.

6. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The high temperature resistant pigment is one of titanium dioxide, carbon black, iron red and 1039N yellow.

7. The flat powder coating for ventilation slots of wind turbines according to claim 1, characterized in that: The filler is silicon micropowder.

8. A method for preparing a flat powder coating for ventilation slots of wind turbines, characterized in that: The method for preparing the flat powder coating according to any one of claims 1 to 7 comprises the following steps: Step S1, premixing: First add 1 / 2 of the epoxy resin, then add other raw materials, and finally add another 1 / 2 of the epoxy resin and stir evenly; Step S2, extrusion: Put the stirred mixed raw materials into the extruder, crush, press roller, extrusion screw in sequence, the screw speed frequency is 40-45Hz, and the feeding screw speed frequency is 20-25Hz; Step S3, grinding: After passing through a 200-220 mesh rotary sieve, the particle size D50 is 30-35 microns. During the grinding process, 0.05-0.1% of powder flow desiccant is mixed.

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