Preparation method of high-temperature-resistant compact enamel glaze

Abstract

The invention belongs to the technical field of enamel glaze preparation, and particularly relates to a high-temperature-resistant compact enamel glaze preparation method, which comprises: 1, enamel frit preparation: mixing 45-65% by mass of silicon dioxide, 10-15% by mass of anhydrous borax, 5-10% by mass of sodium carbonate, 2-6% by mass of lithium carbonate, 2-6% by mass of calcium carbonate, 2-6% by mass of strontium carbonate, and 3-6% by mass of ice crystal to form a batch, melting at 1300 DEG C for 2-3 hours, carrying out water quenching to prepare an enamel material, drying, and sieving with a 200-mesh sieve to obtain enamel frit powder; step 2, preparing enamel glaze slip, namely mixing and ball-milling 40-55% of enamel frit powder, 15-30% of 316 # stainless steel powder, 5.5-10% of clay suspending agent and 25-50% of water in percentage by mass to obtain the enamel glaze slip; and step 3, enamel coating and firing. The enamel coating has excellent high temperature resistance and corrosion resistance and long service life, and the preparation process is simple in requirement, simple and convenient to operate and suitable for industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of enamel preparation, and in particular relates to a method for preparing a high-temperature resistant and dense enamel. Background Art

[0002] Steel plate enamel is a composite material formed by high-temperature firing of inorganic glass glaze and low-carbon steel. It has the high mechanical strength and shape diversity of metal materials, as well as the beautiful appearance and excellent chemical stability of inorganic glass glaze. Enamel materials have been widely used in chemical industry, environmental protection, architectural decoration, sanitary ware, household appliances and other fields. However, the main component of ordinary enamel materials is silicate glass. Although it has excellent chemical stability, silicate glass is easy to soften at high temperatures. The general operating temperature is around 200 degrees, and the high temperature resistance is average, which also limits the further expansion of the application of enamel materials.

[0003] In order to improve the high temperature resistance of enamel materials, the current main method is to adjust the grinding additives of enamel glaze, and add oxides with excellent high temperature resistance, such as alumina, quartz, etc. to the grinding additives of enamel glaze. However, the introduction of these oxides will increase the firing temperature of the enamel, reduce the chemical stability, and improve the high temperature resistance of the enamel. In view of the above situation, it is necessary to invent a high temperature resistant assembled tank enamel material with excellent performance and good chemical stability.

[0004] Therefore, we propose a method for preparing high temperature resistant dense enamel to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing a high temperature resistant dense enamel glaze in view of the above problems.

[0006] To achieve the above object, the present invention provides the following technical solution: a method for preparing a high temperature resistant dense enamel, comprising the following steps:

[0007] Step 1: Enamel frit preparation

[0008] According to mass percentage, 45-65% of silicon dioxide, 10-15% of anhydrous borax, 5-10% of soda ash, 2-6% of lithium carbonate, 2-6% of calcium carbonate, 2-6% of strontium carbonate and 3-6% of ice crystals are mixed into a batch material, melted at 1300° C. for 2-3 hours, quenched with water to obtain an enamel material, and then dried and sieved through a 200-mesh sieve to obtain an enamel frit powder;

[0009] Step 2: Enamel glaze slurry preparation

[0010] According to the mass percentage, 40-55% of enamel frit powder, 15-30% of 316# stainless steel powder, 5.5-10% of clay suspension agent and 25-50% of water are mixed and ball-milled to obtain enamel glaze slurry;

[0011] Step 3: Enamel coating and firing

[0012] The surface of the low-carbon steel plate for enameling is degreased and sandblasted, and then the enamel slurry is coated on the surface of the steel plate, dried at 90-120°C for 20-30 minutes, and then fired at 880-900°C for 10-20 minutes to obtain the assembled tank enamel.

[0013] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step 1, the melting equipment is a silicon-molybdenum rod electric furnace.

[0014] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step 2, the mixing ratio of enamel frit powder, 316# stainless steel powder, clay suspension agent and water is: 45% enamel frit powder, 20% 316 stainless steel powder, 5% clay suspension agent and 30% water; or 40% enamel frit powder, 25% 316 stainless steel powder, 5% clay suspension agent and 30% water; or 50% enamel frit powder, 20% 316 stainless steel powder, 5% clay suspension agent and 25% water.

[0015] In the above-mentioned method for preparing a high-temperature resistant dense enamel glaze, in the step three, the degreasing sandblasting treatment is performed by using an alkaline degreasing agent for degreasing, and then sandblasting is performed with quartz sand with a particle size of 0.5-2 mm at a pressure of 0.3-0.6 MPa.

[0016] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step three, the coating method is spraying or dipping. During spraying, the distance between the spray gun and the surface of the steel plate is maintained at 15-25 cm, and the movement speed of the spray gun is 20-30 cm / s. During dipping, the steel plate is immersed in the enamel slurry for 10-20 seconds, and the withdrawal speed is 5-10 cm / s.

[0017] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step 1, a planetary mixer is used to stir the batch materials for 30-60 minutes at a stirring speed of 50-100 r / min.

[0018] In the above-mentioned method for preparing a high-temperature resistant dense enamel glaze, in the step 2, wet ball milling is adopted during ball milling, the ball milling medium is zirconia ball, the ball-to-material ratio is 3-5:1, the ball milling time is 4-8 hours, and the ball milling speed is 200-300r / min.

[0019] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step three, the drying process is carried out in a hot air circulation oven, the hot air temperature is 90-120° C., and the wind speed is 1-3 m / s.

[0020] In the above-mentioned method for preparing a high-temperature resistant and dense enamel glaze, in the step three, the firing process is carried out in a muffle furnace or a roller kiln, the heating rate during firing is 5-10°C / min, and the cooling rate after firing is 3-5°C / min.

[0021] Compared with the prior art, the present invention provides a method for preparing a high temperature resistant dense enamel glaze, which has the following beneficial effects:

[0022] The preparation method of the high-temperature resistant dense enamel glaze uses 316 stainless steel, which is a stainless steel with excellent chemical stability. The stainless steel has stable mechanical properties at a high temperature of 1000 degrees. In addition, the stainless steel contains enamel glaze adhesives: nickel and molybdenum, etc., which are well combined with the enamel glaze. The grinding additives of the enamel glaze are adjusted, and 316 stainless steel powder with excellent high-temperature resistance and corrosion resistance is added to the enamel glaze grinding additives, which can greatly improve the high-temperature resistance of the enamel surface of the assembled tank, maintain the stability of the structure and performance for a long time, effectively resist high-temperature oxidation and thermal stress deformation, provide reliable protection for extremely high-temperature industrial environments, greatly broaden the high-temperature boundary of enamel application, and significantly improve the high-temperature applicability of enamel compared with traditional enamel. At the same time, it has excellent chemical stability, simple preparation process requirements, and easy operation. It is suitable for industrial production of high-temperature and corrosion-resistant assembled tank enamel materials. DETAILED DESCRIPTION

[0023] The following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0024] Embodiment 1

[0025] A method for preparing a high temperature resistant dense enamel comprises the following steps:

[0026] Step 1: According to mass percentage, 55% of silicon dioxide, 15% of anhydrous borax, 10% of soda ash, 5% of lithium carbonate, 5% of calcium carbonate, 5% of strontium carbonate, and 5% of ice crystals are mixed to obtain a batch material;

[0027] Step 2: Melting the batch material in a silicon-molybdenum rod electric furnace at 1350°C for 2 hours, quenching the melted mixture with water to form an enamel frit, drying the enamel frit, dry-ball milling it and passing it through a 200-mesh sieve to obtain an enamel frit powder;

[0028] Step 3: Mix 45% of enamel frit, 20% of 316 stainless steel powder, 5% of clay suspension and 30% of water according to the mass ratio, and ball-mill to obtain enamel glaze slurry;

[0029] Step 4: Degreasing and sandblasting the surface of the steel plate for enameling, then applying the enamel slurry on the surface of the steel plate, drying at 100° C. for 20 minutes, and firing at 880° C. for 15 minutes to obtain an enamel coating;

[0030] Step 5: The acid resistance of the enamel material was measured according to the national standard GB / T13484-2011 Standard for Food Contact Enamel Products. The test results are shown in Table 1.

[0031] Table 1. Test results of acid and high temperature resistance of enamel materials

[0032] Test performance Acid resistance High temperature resistance Test Results Level AA ≥800 degrees

[0033] Embodiment 2

[0034] A method for preparing a high temperature resistant dense enamel comprises the following steps:

[0035] Step 1: According to mass percentage, 62% of silicon dioxide, 12% of anhydrous borax, 8% of soda ash, 6% of lithium carbonate, 5% of calcium carbonate, 2% of strontium carbonate, and 5% of ice crystals are mixed to obtain a batch material;

[0036] Step 2: Melting the batch material in a silicon-molybdenum rod electric furnace at 1350° C. for 2.5 hours, quenching the melted mixture with water to form an enamel frit, drying the enamel frit, dry-ball milling it and passing it through a 200-mesh sieve to obtain an enamel frit powder;

[0037] Step 3: Mix 40% of enamel frit, 25% of 316 stainless steel powder, 5% of clay suspension and 30% of water according to the mass ratio, and ball-mill to obtain enamel glaze slurry;

[0038] Step 4: Degreasing and sandblasting the surface of the steel plate for enameling, then applying the above-mentioned enamel slurry on the surface of the steel plate, drying at 100° C. for 30 minutes, and firing at 900° C. for 10 minutes to obtain an enamel coating;

[0039] Step 5: The acid resistance of the enamel material was measured according to the national standard GB / T13484-2011 Standard for Food Contact Enamel Products. The test results are shown in Table 2.

[0040] Table 2. Test results of acid and high temperature resistance of enamel materials

[0041] Test performance Acid resistance High temperature resistance Test Results Level AA ≥800 degrees

[0042] Embodiment 3

[0043] A method for preparing a high temperature resistant dense enamel comprises the following steps:

[0044] Step 1: According to mass percentage, 65% of silicon dioxide, 10% of anhydrous borax, 5% of soda ash, 5% of lithium carbonate, 5% of calcium carbonate, 5% of strontium carbonate, and 5% of ice crystals are mixed to obtain a batch material;

[0045] Step 2: Melting the batch material in a silicon-molybdenum rod electric furnace at 1350°C for 3 hours, quenching the melted mixture with water to form an enamel frit, drying the enamel frit, dry-ball milling it and passing it through a 200-mesh sieve to obtain an enamel frit powder;

[0046] Step 3: Mix 50% of enamel frit, 20% of 316 stainless steel powder, 5% of clay suspension and 25% of water according to the mass ratio, and ball-mill to obtain enamel glaze slurry;

[0047] Step 4: Degreasing and sandblasting the surface of the steel plate for enameling, then applying the enamel slurry on the surface of the steel plate, drying at 100° C. for 10 minutes, and firing at 900° C. for 15 minutes to obtain an enamel coating;

[0048] Step 5: The acid resistance of the enamel material was measured according to the national standard GB / T13484-2011 Standard for Food Contact Enamel Products. The test results are shown in Table 3.

[0049] Table 3. Test results of acid and high temperature resistance of enamel materials

[0050] Test performance Acid resistance High temperature resistance Test Results Level AA ≥800 degrees

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a high temperature resistant dense enamel, characterized in that: The steps include: Step 1: Enamel frit preparation According to mass percentage, 45-65% of silicon dioxide, 10-15% of anhydrous borax, 5-10% of soda ash, 2-6% of lithium carbonate, 2-6% of calcium carbonate, 2-6% of strontium carbonate and 3-6% of ice crystals are mixed into a batch material, melted at 1300° C. for 2-3 hours, quenched with water to obtain an enamel material, and then dried and sieved through a 200-mesh sieve to obtain an enamel frit powder; Step 2: Enamel glaze slurry preparation According to the mass percentage, 40-55% of enamel frit powder, 15-30% of 316# stainless steel powder, 5.5-10% of clay suspension agent and 25-50% of water are mixed and ball-milled to obtain enamel glaze slurry; Step 3: Enamel coating and firing The surface of the low-carbon steel plate for enameling is degreased and sandblasted, and then the enamel slurry is coated on the surface of the steel plate, dried at 90-120°C for 20-30 minutes, and then fired at 880-900°C for 10-20 minutes to obtain the assembled tank enamel.

2. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step 1, the melting equipment is a silicon-molybdenum rod electric furnace.

3. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step 2, the mixing ratio of enamel frit powder, 316# stainless steel powder, clay suspension agent and water is: 45% enamel frit powder, 20% 316 stainless steel powder, 5% clay suspension agent and 30% water; or 40% enamel frit powder, 25% 316 stainless steel powder, 5% clay suspension agent and 30% water; or 50% enamel frit powder, 20% 316 stainless steel powder, 5% clay suspension agent and 25% water.

4. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step three, the degreasing sandblasting treatment is performed by using an alkaline degreasing agent to perform degreasing treatment, and then using quartz sand with a particle size of 0.5-2 mm to perform sandblasting at a pressure of 0.3-0.6 MPa.

5. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step three, the coating method is spraying or dipping. During spraying, the distance between the spray gun and the steel plate surface is maintained at 15-25 cm, and the spray gun moves at a speed of 20-30 cm / s. During dipping, the steel plate is immersed in the enamel slurry for 10-20 seconds, and the withdrawal speed is 5-10 cm / s.

6. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step 1, the batch materials are mixed by a planetary mixer for 30-60 minutes at a stirring speed of 50-100 r / min.

7. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step 2, wet ball milling is adopted for ball milling, the ball milling medium is zirconia ball, the ball-to-material ratio is 3-5:1, the ball milling time is 4-8 hours, and the ball milling speed is 200-300 r / min.

8. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step 3, the drying process is carried out in a hot air circulation oven, the hot air temperature is 90-120° C., and the wind speed is 1-3 m / s.

9. The method for preparing a high temperature resistant dense enamel according to claim 1, characterized in that: In the step three, the firing process is carried out in a muffle furnace or a roller kiln, the heating rate during firing is 5-10°C / min, and the cooling rate after firing is 3-5°C / min.