Spraying curing method of ceramic fiber spraying material

Abstract

The invention provides a spraying curing method of a ceramic fiber spraying material.The spraying curing method comprises the following steps of S1, base layer pretreatment, S2, non-spraying area protection, S3, spraying construction, S4, curing protection, S5, follow-up maintenance and S6, acceptance detection.A silane coupling agent pretreatment technology is adopted, a stable slow-release film is formed on the surface of fiber cotton, and a metal net mechanical anchoring structure is matched, so that the surface of the fiber cotton is protected; the interface bonding of ceramic fibers and a matrix is remarkably enhanced, thermal expansion stress is effectively resisted through the synergistic effect of chemical bonding and physical occlusion, the problems of hollowing and falling caused by insufficient interface bonding force in a traditional process are solved, infrared heating and a nano curing agent technology are integrated, the curing process is accelerated, a compact film layer is formed, the curing period is shortened, and the curing efficiency is improved. The microcapsule technology optimizes a heat conduction path, the layered spraying technology inhibits thermal stress concentration, the overall heat preservation performance of the coating is improved, heat loss is reduced, and the heat insulation requirement of high-temperature equipment is met.

Description

Technical Field

[0001] The present invention belongs to the field of thermal insulation construction of industrial equipment, and particularly relates to a spraying and curing method for ceramic fiber spraying materials. Background Art

[0002] The curing method of ceramic fiber spraying mainly relies on natural drying or drying, combined with the use of curing agents and environmental control to ensure that the coating is uniform, hardened and meets the design performance. The specific process needs to be adjusted with reference to the material specification and application scenario.

[0003] Publication No. CN105130475A discloses a low-temperature curing spraying material, which can be cured by self-bonding without sintering at low temperature to form a high-strength integral lining, significantly reducing material consumption and achieving the purpose of energy conservation and emission reduction. However, in the ceramic fiber spraying process, the combination between ceramic fiber and metal matrix mainly relies on mechanical biting, and the interfacial bonding force is insufficient. In a high-temperature environment, thermal expansion stress is likely to cause the coating to be hollow and fall off, seriously affecting the thermal insulation effect and structural stability.

[0004] Therefore, in view of this problem, the present invention provides a spraying and curing method for ceramic fiber spraying materials. Summary of the Invention

[0005] In order to solve the above technical problems, the present invention provides a spraying and curing method for ceramic fiber spraying materials to solve the problems raised in the background art.

[0006] A spraying and curing method for ceramic fiber spraying materials includes the following steps:

[0007] S1 Substrate pretreatment: Manually clean the surface of the substrate, check and fasten the hanging parts and embedded parts, and at the same time wrap the silane coupling agent with the delayed hydrolysis silane precursor technology;

[0008] S2 Protection of non-spraying areas: Adopt three-level protection measures, wrap some areas in the equipment with polytetrafluoroethylene film, stuff the pipeline with fiber blankets and cover it with iron sheets, and lay polyethylene boards on the ground;

[0009] S3 Spraying construction: Select appropriate ceramic fiber spraying materials and spraying thickness according to the temperature and expansion amount of the equipment, mix ceramic fiber cotton, binder and microcapsules in a mass ratio of 100:40:5, add nano-silica as a dispersant, and embed metal meshes during the spraying process;

[0010] S4 Curing and protection: Conduct moisture-proof treatment on the external environment, stick protective materials on the parts prone to collision, and at the same time conduct local repair on the damaged parts of the coating;

[0011] S5 Subsequent maintenance: After the coating is cured, apply a curing agent to the surface of the sprayed coating, and then cover the sprayed area with a plastic film;

[0012] S6 Acceptance test: Conduct an acceptance test on the heat preservation effect according to relevant documents.

[0013] Preferably, the concentration of the silane coupling agent solution is 5%-10%, and the coating amount of the silane coupling agent solution is 0.1-0.2 kg / m 2 。

[0014] Preferably, the material of the metal mesh is 304 stainless steel, the mesh size is 10 mm×10 mm, and the wire diameter is 0.5 mm.

[0015] Preferably, the curing agent is composed of portland cement, fly ash and water, and the ratio of portland cement, fly ash and water is 1:0.5:0.3.

[0016] Preferably, the dosage of the curing agent is 0.3-0.5 kg / m 2 。

[0017] Preferably, the covering thickness of the plastic film should be not less than 0.1 mm.

[0018] Preferably, the curing protection includes moisture-proof and waterproof measures, mechanical collision protection and local damage repair;

[0019] Preferably, the spraying thickness range is 20-30 mm.

[0020] Preferably, the laying spacing of the metal mesh is 150-200 mm.

[0021] Preferably, the environmental temperature range is maintained at 10-35 °C during the covering of the plastic film.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. In the use of the present invention, the silane coupling agent pretreatment technology is adopted to form a stable slow-release film on the surface of the fiber cotton, and combined with the mechanical anchoring structure of the metal mesh, the interfacial bonding between the ceramic fiber and the matrix is significantly enhanced. Through the synergistic effect of chemical bonding and physical occlusion, the thermal expansion stress can be effectively resisted, and the problems of hollowing and falling off caused by insufficient interfacial bonding force in the traditional process are solved.

[0024] 2. In the use of the present invention, the infrared heating and nano-curing agent technologies are integrated to accelerate the curing process and form a dense film layer, shortening the curing cycle. The microcapsule technology optimizes the heat conduction path, and the layered spraying process inhibits the concentration of thermal stress, improving the overall heat insulation performance of the coating, reducing heat loss, and meeting the heat insulation requirements of high-temperature equipment.

[0025] 3. During the use of the present invention, through the embedding of the metal mesh and the application of the nano-dispersant, the cohesive force within the coating and the ability to disperse thermal stress are enhanced, and the structural strength is improved. Under the synergistic effect of the full-process technology, the coating has excellent impact resistance and anti-cracking performance. Dynamic tests show good long-term stability, meeting the lasting use requirements under complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a schematic diagram of the basic process structure of the method of the present invention;

[0027] Figure 2 is a schematic diagram of the process of step S1 of the present invention;

[0028] Figure 3 is a schematic diagram of the process of step S1 of the present invention;

[0029] Figure 4 is a schematic diagram of the comparative structure of the embodiment of the present invention;

[0030] Figure 5 is a graph showing the relationship between the curing time and the adhesion of the ceramic fiber spraying material in different embodiments of the present invention;

[0031] Figure 6 is a graph showing the change trend of the curing time and the tensile strength of the ceramic fiber spraying material in different embodiments of the present invention;

[0032] Figure 7 is a graph showing the change trend of the curing time and the surface temperature of the ceramic fiber spraying material in different embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The following further describes in detail the embodiments of the present invention with reference to the drawings and embodiments. The following embodiments are used to illustrate the present invention, but cannot be used to limit the scope of the present invention.

[0034] A spraying and curing method for a ceramic fiber spraying material includes the following steps:

[0035] S1 Substrate pretreatment: Manually clean the surface of the substrate, check and fasten the hanging parts and embedded parts, and at the same time wrap the silane coupling agent using the delayed hydrolysis silane precursor technology;

[0036] Among them, in the primary pretreatment, during the cleaning process, dust, debris, oil stains, etc. on the surface of the primary layer should be thoroughly removed to ensure the effect of subsequent treatment. For hanging parts and embedded parts, professional tools are required to check for looseness, damage, etc. If there are problems, they should be tightened or replaced in a timely manner. At the same time, the delayed hydrolysis silane precursor technology is used to treat the silane coupling agent. The silane coupling agent selected is γ-aminopropyltriethoxysilane (KH550), and its purity should be ≥98% to ensure good chemical activity. It is mixed with a citric acid solution with a concentration of 0.75wt%. The pH value of this citric acid solution should be controlled at 3.8±0.2, so as to form a stable precursor solution. In terms of the spray drying process, the inlet temperature should be controlled at 182±3°C, the outlet temperature is 85±2°C, the treatment line speed of the fiber cotton is 0.8m / min, and the solution atomization pressure is 0.62MPa. The precise control of these parameters can make the silane evenly loaded on the surface of the fiber cotton. After treatment, the silane loading amount on the surface of the fiber cotton should be 1.8±0.3wt% detected by XRF, and the thickness of the formed slow-release film observed by SEM is between 1.2 - 2.8μm;

[0037] In addition, the primary layer cleaning also adopts a process combining mechanical grinding and chemical cleaning. First, an electric wire brush with a rotation speed of 1500rpm is used to effectively remove the scale on the surface of the primary layer, making the roughness of the primary layer reach Ra63μm. Then, the primary layer is wiped with acetone with a purity ≥99.5% to remove oil stains, and the residue amount is required to be ≤0.05mg / cm 2 , which can be detected by FT IR. For the tightening of the hanging parts, a torque wrench (model Tohnichi CBW-100) is used. The tightening torque of alloy steel bolts (grade 8.8) is controlled at 85±5N·m, and that of carbon steel bolts (grade 4.8) is 55±3N·m to ensure the stability of the hanging parts;

[0038] Finally, the construction environment has an important impact on the pretreatment effect. A temperature and humidity automatic recorder (Testo175-H1) is required to monitor the environment in real time. During the construction period, the humidity should be ≤58%RH, and the temperature should be maintained at 18 - 28°C. After the pretreatment is completed, a contact angle measuring instrument (OCA20) is used to detect the water contact angle on the surface of the primary layer, which is required to be ≥90°, indicating the integrity of the silane film. At the same time, an ultrasonic flaw detector (USM35X) is used to detect the anchoring depth of the hanging parts, which is required to be ≥50mm, meeting the standard requirements of GB50205.

[0039] S2 Non-spraying Area Protection: Adopt three-level protection measures. Wrap some areas in the equipment with polytetrafluoroethylene film, stuff the pipes with fiber blankets and cover them with iron sheets, and lay polyethylene boards on the ground;

[0040] Among them, the protection of non-spraying areas adopts a three-level protection system. For some areas in the equipment, a polytetrafluoroethylene film with a thickness of 0.3 mm is used for wrapping. The density of this polytetrafluoroethylene film is 2.1 - 2.3 g / cm 3 , and it can withstand temperatures up to 327 °C, which can effectively protect the equipment from the influence of spraying materials. The joints of the film are sealed with high-temperature resistant tape (3M69), and its peel strength ≥ 5 N / cm to ensure the sealing effect. For pipelines, aluminosilicate fiber blankets are used for stuffing. The density of this fiber blanket is 128 kg / m 3 , the slag ball content ≤ 4%, and the compression and rebound rate ≥ 90%, which can well fill the pipeline gap. After stuffing, it is covered with 0.8 mm galvanized iron sheet, and its coating amount ≥ 85 g / m 2 , enhancing the protection performance. On the ground, a 3 mm thick high-density polyethylene board is laid, and its density is 0.941 - 0.965 g / cm 3 , the tensile strength ≥ 22 MPa, and expansion bolts (M8×80 mm, material Q235B) are used for anchoring, and the anchoring spacing is 450 ± 20 mm to ensure the stability of the ground protection;

[0041] In addition, the shielding structure adopts a triangular support frame, which is made of Q235B steel, with a cross-sectional size of 50×50×3 mm, and the frame spacing is 1.4 ± 0.1 m. It is verified by finite element analysis (ANSYS Workbench). Under the load of 1.5 kPa, the maximum deformation ≤ 3 mm to ensure the stability of the structure. When stuffing the pipeline, a laser thickness gauge (TT100) is used for detection, and it is required that the stuffing depth ≥ 1 / 2 of the pipe diameter, and the filling rate ≥ 97% to ensure the protection effect;

[0042] Finally, the airtightness test is an important part of the protection work. An aerosol photometer (TSI8130) is used for detection, and the leakage rate of particles with a diameter of 0.3 - 5 μm is detected, and it is required that ≤ 0.01% to ensure good airtightness of the protected area. After clearing the obstacles, a three-dimensional laser scanner (Leica ScanStation C10) is used for mapping to ensure that the space size can meet the movement range of the spraying robotic arm (model KUKA KR16), and the minimum operating radius is 3.6 m.

[0043] S3 Spraying Construction: Select appropriate ceramic fiber spraying materials and spraying thickness according to the temperature and expansion amount of the equipment. Mix ceramic fiber cotton, binder, and microcapsules in a mass ratio of 100:40:5, and add nano-silica as a dispersant, and embed a metal mesh during the spraying process;

[0044] Among them, in the spraying construction, first, appropriate ceramic fiber spraying materials and spraying thickness should be selected according to the temperature and expansion amount of the equipment. When mixing the materials, ceramic fiber cotton (diameter 2 - 4μm, length 30 - 50mm), binder (silica sol solid content 35%, alumina sol solid content 40%), and silicon alkane - loaded fiber cotton are mixed in a mass ratio of 100:40:5. A planetary mixer (model ThinkyARE - 310) is used, with a rotation speed of 200 rpm and a mixing time of 15 min ± 30 s. Meanwhile, 0.3 wt% of nano - silica (particle size 18 nm, specific surface area 200 m 2 / g) is added as a dispersant. After mixing, the viscosity of the mixed liquid is measured using a Brookfield DV2T viscometer at a rotation speed of 20 rpm. The requirement is 2300 ± 200 mPa·s, and the thixotropic index is between 1.5 - 1.8 to ensure the good fluidity and construction performance of the mixed liquid;

[0045] In addition, the control of spraying process parameters is crucial. A twin - screw pump (model Moyno2000) is used for transportation, with a transportation volume of 12 L / min, a spray gun pressure of 0.7 ± 0.05 MPa, and a nozzle diameter of 3.0 mm (air cap model SATAjet5000). When spraying in layers, the thickness of each layer is controlled at 30 - 40 mm, and the interval time between layers is 15 min. An infrared thermal imager (FLIRT640) is used to monitor the temperature difference between layers, and the requirement is ≤12℃. When a metal mesh (304 stainless steel, wire diameter 0.5 mm, grid 10×10 mm) is embedded in the coating, the embedding depth is 12 - 18 mm, and the overlap width is 50 ± 5 mm to enhance the structural strength of the coating;

[0046] Finally, the construction environment has a significant impact on the spraying quality. An anemometer (Testo425) is used to monitor the wind speed, and the requirement is that the wind speed ≤2.5 m / s. At the same time, the construction temperature is controlled at 15 - 32℃, and the humidity ≤70%RH. An ultrasonic thickness gauge (Olympus38DL) is used to scan the coating to detect the uniformity of the coating. The single - point thickness deviation should ≤±2.5%. A high - speed camera (Phantom v2512) is used to record the spraying process, and image analysis software (ImageJ) is used for analysis. The requirement is that the micro - capsule rupture rate ≥92% to ensure the effective function of the silane coupling agent.

[0047] S4 Curing and Protection: Conduct moisture - proof treatment on the external environment, adhere protective materials to easily - collided parts, and at the same time, conduct local repair on the damaged positions of the coating;

[0048] Among them, the solidification protection work starts with moisture-proof treatment. A two-component polyurethane coating is used for moisture-proofing. The ratio of A / B components of the coating is 1:2, and the solid content is 98.5%. According to the GB / T1728 standard, the surface drying time should be ≤2h, and the actual drying time is 24h. A magnetic thickness gauge (TT260) is used to measure the coating thickness, and the requirement is 1.5±0.1mm. The tensile strength of this coating is 12.3MPa, and the elongation at break is 450%, which can effectively prevent moisture penetration. At the same time, a quartz tube heater is used for infrared heating, with a power of 1.5kW / m 2 , and the heating time is 4h. The surface temperature is controlled at 60±5℃ through thermocouple temperature measurement to accelerate the curing process;

[0049] In addition, for easily collidable parts, high-density polyethylene foam is used for protection. The density of this foam is 30kg / m 3 , the compressive strength is 0.15MPa, and the thickness is 50±2mm. Epoxy resin adhesive is used for pasting, and its shear strength is 15MPa to ensure the firmness of the protective material. An impact testing machine (Instron9250HV) is used to test the impact resistance of the protective material, and the requirement is ≥50kJ / m 2 . When there is a damaged position on the coating, it is repaired according to the ratio of fiber cotton: binder = 1:0.4. After repair, it is infrared baked for 4h, and the baking temperature is 80℃, and ultrasonic flaw detection is carried out to ensure no defects;

[0050] Finally, during the curing process, a temperature and humidity recorder (HOBOMX2301) is used to continuously monitor the environment. It is required that the humidity fluctuation during curing is ≤±5%RH. A pull-out test (Zwick / Roell Z010) is carried out on the repair area, and the bond strength should be ≥0.2MPa. At the same time, thermal imaging detection is used, and the temperature difference should be ≤3℃. The degree of silane hydrolysis is detected by FTIR and compared with the standard spectrum. The peak intensity at 1080cm -1 should reach 92% to ensure that the silane is fully hydrolyzed and plays a role.

[0051] S5 Follow-up maintenance: After the coating is cured, a curing agent is applied to the surface of the sprayed coating, and then the sprayed area is covered with a plastic film;

[0052] Among them, after the coating is cured, follow-up maintenance work needs to be carried out. At this time, the curing agent is prepared according to the mass ratio of P.O42.5 Portland cement, fly ash and water of 1:0.5:0.3. Its slump should be controlled at 180±20mm, which meets the GB / T50080 standard. A high-pressure airless spraying equipment (model GracoX7) is used for spraying. The spraying pressure is 15MPa, the nozzle aperture is 0.4mm, and the spraying amount is 0.35±0.03kg / m 2, use coating thickness gauge (TT260) to detect film thickness, requiring film thickness uniformity deviation ≤ ± 4%, air permeability ≤ 0.01mm / s, in line with GB / T25181 standard, to ensure the curing effect;

[0053] In addition, the sprayed area was covered with LLDPE film, the density of which was 0.915 g / cm 3 , thickness is 0.1±0.01mm, tensile strength is 25MPa, elongation at break is 350%, pressure-sensitive tape (Tesa4972) is used for fixing when covering, edge overlap width is 15±2mm, air tightness test is carried out according to GB / T7141 standard, leakage rate is required to be ≤0.05m 3 / (m·h), to ensure good coverage;

[0054] Finally, the curing period is calculated according to the accumulated temperature method. When the ambient temperature is 25°C, the curing time is 7 days (accumulated accumulated temperature is 175°C·d); when the ambient temperature is 15°C, the curing time is 10 days (accumulated accumulated temperature is 150°C·d). In the rainy season, a rain shelter is required to be built with a slope of 15° and a drainage capacity of 50 mm / h. At the same time, a drainage ditch with a size of 200×200 mm is set up. Before removing the film, a halogen moisture meter (MA35) is used to detect the moisture content of the coating, which is required to be ≤7% to ensure that the coating is fully cured.

[0055] S6 Acceptance test: Carry out acceptance test on insulation effect according to relevant documents.

[0056] Among them, the acceptance test is carried out in accordance with the three-level inspection standard and the "Guidelines for Fire Resistance and Insulation Maintenance of Thermal Equipment in Thermal Power Plants DL / T936" document. Then, an infrared thermal imager (FLIRA655sc) is used for inspection, with an accuracy of ±0.3℃ and a scanning interval of ≤0.5m. If the temperature difference in the inspection area is greater than 8℃, it is judged as unqualified. Secondly, the heat flow meter method (model Huksef l uxHFP01) is used for testing, with a sensor accuracy of ±1.5% and a measurement point arrangement density of 1 point / 8m 2 According to GB / T2586 standard, heat loss should be ≤145W / m 2 Finally, a destructive test is conducted, and 5% of the test points are randomly selected. The thickness deviation is tested using relevant testing equipment, and the requirement is ≤±2.5%. The pull-out strength is required to be ≥0.18MPa, which complies with the GB / T50365 standard.

[0057] In addition, dynamic detection is also required. Let the device run for 72 hours with a load of 80%. Use a temperature recorder (OM-64K) to record the temperature fluctuations. The temperature fluctuations are required to be within ±4°C. Establish a finite element model (ANSYS19.2) for analysis. The model parameters are set as thermal conductivity 0.042 W / (m·K), density 180 kg / m 3 , specific heat capacity 1000 J / (kg·K). The analysis result requires the maximum principal stress ≤ 1.1 MPa;

[0058] Finally, acoustic emission detection (PACPCI-2) is adopted. Set the threshold to 40 dB. The ringdown count is required to be ≤ 95 times / m 2 , use a three-dimensional point cloud scanner (Trimble TX8) to establish a three-dimensional point cloud model with a resolution of 0.1 mm. Mark the defects in the model. The marking rate needs to reach 100%. The acceptance report needs to include the signatures of the five parties of construction, design, construction, supervision, and detection, and attach the original detection data and rectification records to ensure the accuracy and integrity of the acceptance work.

[0059] Example 1: General steps to achieve spraying and curing (traditional method);

[0060] The steps are as follows:

[0061] S1: Manually clean the base layer;

[0062] S1: Protect the non-spraying area;

[0063] S3: Spray a single layer of ceramic fiber material (thickness 80 mm);

[0064] S4: Natural curing.

[0065] Table 1: Data comparison table after achieving spraying and curing by general steps

[0066] Test item Result Adhesion (MPa) 0.25 Curing time (h) 72 Surface temperature (°C) 480 (environment 550°C) Tensile strength (MPa) 0.40

[0067] As can be seen from Table 1, in this example, the traditional single-layer spraying process is adopted without introducing any innovative technologies. The test data shows that its adhesion is only 0.25 MPa, and the interface bonding force is weak due to complete reliance on mechanical occlusion; the curing time is as long as 72 hours, and the curing efficiency is low due to complete reliance on natural curing; the surface temperature of 480°C (ambient temperature 550°C) indicates insufficient heat preservation performance; the tensile strength of 0.40 MPa shows that the coating structure strength is weak. This process has inherent defects such as low bonding force, slow curing, poor heat preservation, and easy cracking.

[0068] Example 2: Only metal mesh embedding;

[0069] The steps are as follows:

[0070] S1 Spraying construction: Layered spraying + Embedding metal mesh (304 stainless steel, mesh 10mm×10mm) S2 Other steps are the same as in Example 1;

[0071] Table 2: Data comparison table after spraying and curing only after embedding metal mesh:

[0072] Test item Result Adhesion (MPa) 0.26(+4％) Curing time (h) 72 Surface temperature (°C) 450 (environment 550°C) Tensile strength (MPa) 0.65(+62.5％)

[0073] It can be seen from Table 2 that in this example, by layered spraying and embedding 304 stainless steel metal mesh, a technological breakthrough is achieved because the metal mesh forms a mechanical anchoring structure, significantly improving the cohesion of the coating and the ability to disperse thermal stress. The data shows that the tensile strength is increased to 0.65 MPa (+62.5%), and the surface temperature is reduced to 450 °C (-,100 °C), verifying the optimization effect of the mesh structure on mechanical properties and heat preservation efficiency, and effectively solving the problem of easy cracking of the coating.

[0074] Example 3: Only pretreatment with silane coupling agent;

[0075] The steps are as follows:

[0076] S1 Substrate pretreatment: Brushing with silane coupling agent (concentration 5%, dosage 0.1 kg / m 2 )

[0077] S2 Other steps are the same as in Example 1;

[0078] Table 3: Data comparison table after spraying and curing only after pretreatment with silane coupling agent:

[0079]

[0080]

[0081] It can be seen from Table 3 that in this example, the silane coupling agent pretreatment process is introduced, and a chemical bonding is formed at the interface using a 5% concentration solution (0.1 kg / m 2 ) The adhesion is increased to 0.42 MPa (+68%), and the surface temperature is reduced to 460 °C (-90 °C), confirming that the chemical bonding significantly enhances the interface bonding and reduces the thermal bridge effect, solving the core problem of insufficient interface bonding force in the traditional process.

[0082] Example 4: Only maintenance with curing agent;

[0083] The steps are as follows:

[0084] S1 Subsequent maintenance: Brushing with curing agent (Portland cement: Fly ash: Water = 1:0.5:0.3)

[0085] S2 Other steps are the same as in Example 1;

[0086] Table 4: Data comparison table of spraying and curing after maintenance with curing agent only:

[0087] Test item Result Adhesion (MPa) 0.26(+4％) Curing time (h) 48(-33％) Surface temperature (°C) 430 (environment 550°C) Tensile strength (MPa) 0.40

[0088] As can be seen from Table 4, in this embodiment, the curing is optimized by the silicate cement-based curing agent (1:0.5:0.3). The curing time is shortened to 48 hours (-33%), and the surface temperature is further reduced to 430 °C (-120 °C), indicating that the curing agent accelerates the curing process and forms a dense film layer, effectively solving the problems of long curing cycle and loose surface.

[0089] Example 5: Operate according to the steps S1 to S6 described above;

[0090] The steps are as follows:

[0091] S1 Substrate pretreatment: silane coupling agent;

[0092] S2 Protection of non-sprayed areas;

[0093] S3 Spraying construction: lay metal meshes in layers;

[0094] S4 Curing protection;

[0095] S5 Subsequent maintenance: add curing agent;

[0096] S6 Acceptance inspection.

[0097] Table 5: Data table after the spraying and curing method using the ceramic fiber spraying material described above:

[0098] Test item Result Adhesion (MPa) 0.40(+100％) Curing time (h) 48(-33％) Surface temperature (°C) 95 (environment 550°C) Tensile strength (MPa) 0.65(+87.5％)

[0099] As can be seen from Table 5, in this embodiment, through the integration of the whole-process innovative process (S1 - S6), through the synergistic effects of technologies such as delaying the hydrolysis of silane precursors, three-level protection, layered metal meshes, infrared curing, and nano-curing agents, comprehensive performance breakthroughs are achieved: the adhesion reaches 0.50 MPa (+100%), the tensile strength is 0.75 MPa (+87.5%), the surface temperature is 95 °C (-455 °C), and the curing time remains 48 hours. Compared with the traditional process, the adhesion doubles, the tensile strength is nearly doubled, the heat preservation performance is increased by 22%, the construction efficiency and quality are optimized synchronously, breaking through the bottleneck of single technology, and the comprehensive performance reaches the best.

[0100] In summary, through the systematic analysis of the five embodiments, the data differences of the three key variables of adhesion, tensile strength, and surface temperature intuitively reflect the performance changes after the application of traditional processes and innovative technologies. To more clearly show the change trends of each variable and the optimization effect of innovation points on performance, three groups of line charts are specially drawn for comparative analysis. The following will be combined with Figure 1 Adhesion line chart, Figure 2Tensile strength line chart, Figure 3 Surface temperature line chart, to analyze the performance of each embodiment in different dimensions:

[0101] From the appendix Figure 5 It can be seen that: In Example 1, the traditional process is adopted, relying on manual cleaning of the base layer, single-layer spraying and natural curing. The interface bonding only depends on mechanical interlocking, and the bonding force is weak, resulting in an adhesion of only 0.25 MPa, exposing the problem of insufficient interface bonding force in the traditional process;

[0102] Among them, in Example 2, a layered spraying and embedded metal mesh is added. The metal mesh focuses on improving the coating structure strength and dispersing thermal stress, and has limited improvement on the interface bonding force. Therefore, the adhesion only increases to 0.26 MPa (+4%), indicating that the metal mesh is effective in enhancing the structure, but does not significantly optimize the interface bonding force;

[0103] In addition, in Example 3, a silane coupling agent pretreatment is introduced. The silane forms a chemical bond (Si-O-Si bond) at the interface, and the chemical bond strength is higher than mechanical interlocking, increasing the adhesion to 0.42 MPa (+68%), directly solving the core problem of insufficient interface bonding force in the traditional process;

[0104] And in Example 4, a curing agent is used for maintenance. The curing agent acts on the curing process and surface compactness, and has no direct enhancement on the interface bonding force. Therefore, the adhesion remains at 0.26 MPa (+4%), indicating that the curing agent solves the problems of curing cycle and surface looseness, rather than the interface bonding force problem;

[0105] Finally, in Example 5, according to the spraying and curing method described in the present invention, the silane coupling agent enhances the interface chemical bonding, and the metal mesh is embedded to strengthen the interface mechanical anchoring. Under the synergistic effect of multiple technologies, the adhesion reaches 0.50 MPa (+100%). The dual action of silane and metal mesh enhances the interface bonding through chemical bonding and mechanical structure together, breaks through the limitations of single technology, realizes a large increase in adhesion, comprehensively solves the defect of low interface bonding force in the traditional process, and makes the comprehensive performance reach the optimal.

[0106] From the appendix Figure 6 It can be seen that: In Example 1, the traditional process is adopted, only relying on single-layer spraying and natural curing. The coating structure is single, and there is a lack of reinforcement structure inside, resulting in a tensile strength of only 0.40 MPa, reflecting that the traditional process is difficult to meet the high-strength requirements due to simple structure and insufficient bonding force, and has the defect of easy cracking;

[0107] Among them, in Example 2, a layered spraying and embedded metal mesh is added. The metal mesh forms a mechanical anchoring structure, disperses the internal stress of the coating and improves the cohesion. This innovation increases the tensile strength to 0.65 MPa (+62.5%). Because the metal mesh enhances the overall structure strength of the coating, it effectively solves the cracking problem caused by stress concentration in the coating;

[0108] In addition, in Example 3, silane coupling agent pretreatment was introduced. The silane formed chemical bonding at the interface, mainly optimizing the interfacial bonding force. Although the adhesion was significantly improved, the impact on the overall tensile strength of the coating was small, only increasing to 0.41 MPa (+2.5%). Because the silane coupling agent focused on interfacial modification and did not change the internal structural strength of the coating;

[0109] Then in Example 4, a curing agent was used for maintenance. The main function of the curing agent was on the curing process and surface densification, and it did not directly enhance the internal structural strength of the coating. Therefore, the tensile strength was maintained at 0.40 MPa, the same as in Example 1, indicating that the curing agent solved the problems of curing cycle and surface looseness, rather than the structural strength problem;

[0110] Finally, in Example 5, according to the spraying and curing method described in the present invention, the silane coupling agent enhanced the interfacial bonding, and the metal mesh optimized the internal structure. The synergistic effect of multiple technologies made the tensile strength reach 0.75 MPa (+87.5%). Because the silane improved the interfacial bonding force and the metal mesh enhanced the structural framework, the dual effects optimized the mechanical properties of the coating, broke through the limitations of single technology, achieved a substantial increase in tensile strength, solved the core problem of insufficient structural strength in traditional processes, and made the comprehensive performance reach the optimal.

[0111] From the atta Figure 7 It can be seen that in Example 1, the traditional process was adopted without innovative technology. The base layer was manually cleaned, and after single-layer spraying, natural curing was carried out, relying only on mechanical interlocking. The interfacial bonding force was weak, resulting in an adhesion of only 0.25 MPa; the single-layer spraying structure was loose, the heat preservation performance was insufficient, and the surface temperature reached 480 °C; the coating structure was single, and the tensile strength was only 0.40 MPa, having problems such as low bonding force, slow curing, poor heat preservation, and easy cracking;

[0112] And in Example 2, layered spraying and embedding of metal meshes were added. At this time, the metal meshes formed a mechanical anchoring structure, and the metal meshes began to disperse the thermal stress and at the same time increased the cohesive force of the coating, which increased the tensile strength to 0.65 MPa (+62.5%). Because the metal meshes enhanced the structural strength; the surface temperature dropped to 450 °C. Because the mesh structure optimized the fiber arrangement and reduced the thermal conductivity, effectively solving the problem of easy cracking of the coating;

[0113] In addition, in Example 3, silane coupling agent pretreatment was introduced. At this time, the silane formed chemical bonding (Si-O-Si bond) at the interface, enhancing the interfacial wetting and reducing pores. Therefore, the adhesion increased to 0.42 MPa (+68%). Because the chemical bonding strength was higher than mechanical interlocking, the surface temperature dropped to 460 °C. Because the interfacial optimization reduced the thermal bridge effect, solving the core problem of insufficient interfacial bonding force in traditional processes;

[0114] Then, in Example 4, a curing agent was used for maintenance. At this time, the curing agent formed a dense film layer, reducing water loss, promoting the secondary hydration of the binder, and shortening the curing time to 48 hours (-33%) because the film layer accelerated the curing process; the surface temperature dropped to 430 °C because the film layer reduced heat loss, solving the problems of long curing cycle and loose surface;

[0115] Finally, in Example 5, according to the spraying and curing method described in the present invention, the silane coupling agent enhanced the interfacial bonding, the metal mesh improved the structural strength, and the curing agent accelerated the curing, resulting in a multi-technology synergistic effect. At the same time, the adhesion reached 0.50 MPa (+100%) because of the double enhancement of the interface by the silane and the metal mesh; the tensile strength was 0.75 MPa (+87.5%) because of the structural optimization; the surface temperature was 95 °C, achieving comprehensive heat preservation improvement; the curing time remained 48 hours, and the full-process technology broke through the single technology bottleneck, realizing the comprehensive improvement of adhesion, strength, heat preservation, and construction efficiency, solving the multiple defects of the traditional process, and making the comprehensive performance reach the optimal.

[0116] All modes of the present invention are within the scope of patent protection of this patent.

[0117] The embodiments of the present invention are given for the purpose of illustration and description. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A spraying and curing method for a ceramic fiber spraying material, characterized in that, It includes the following steps: S1 Substrate pretreatment: Manually clean the substrate surface, check and fasten the hanging parts and embedded parts, and at the same time wrap the silane coupling agent using the delayed hydrolysis silane precursor technology; S2 Protection of non-spraying areas: Adopt three-level protection measures. Wrap some areas in the equipment with polytetrafluoroethylene film, fill the pipes with fiber blankets and cover them with iron sheets, and lay polyethylene sheets on the ground; S3 Spraying construction: Select appropriate ceramic fiber spraying materials and spraying thickness according to the temperature and expansion amount of the equipment. Mix ceramic fiber cotton, binder and microcapsules in a mass ratio of 100:40:5, and add nano-silica as a dispersant. At the same time, embed a metal mesh during the spraying process; S4 Curing and protection: Conduct moisture-proof treatment on the external environment, adhere protective materials to the parts prone to collision, and at the same time conduct local repair on the damaged positions of the coating; S5 Follow-up maintenance: After the coating is cured, apply a curing agent on the surface of the sprayed coating, and then cover the sprayed area with a plastic film; S6 Acceptance inspection: Conduct acceptance tests on the heat preservation effect according to relevant documents.

2. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that The concentration of the silane coupling agent solution is 5%-10%, and the coating amount of the silane coupling agent solution is 0.1-0.2 kg / m².

3. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The material of the metal mesh is 304 stainless steel, the mesh size is 10 mm×10 mm, and the wire diameter is 0.5 mm.

4. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The curing and protection includes moisture-proof and waterproof measures, mechanical collision protection and local damage repair.

5. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The curing agent is composed of Portland cement, fly ash and water, and the ratio of Portland cement, fly ash and water is 1:0.5:0.

3.

6. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The dosage of the curing agent is 0.3-0.5 kg / m².

7. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The covering thickness of the plastic film is not less than 0.1 mm.

8. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, The spraying thickness range is 20-30 mm.

9. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that The laying spacing of the metal mesh is 150-200 mm.

10. The spraying and curing method of the ceramic fiber spraying material according to claim 1, characterized in that, During the covering of the plastic film, the ambient temperature is maintained in the range of 10-35°C.

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