Tempering process of high-strength 2.0 mm coated photovoltaic glass

Abstract

The invention relates to the technical field of photovoltaic glass processing, and discloses a tempering process of high-strength 2.0 mm coated photovoltaic glass, the process comprises cleaning treatment, coating treatment, curing treatment, tempering treatment and post-treatment, surface impurities and moisture are removed through the cleaning treatment, meanwhile, a nano-scale porous silicon dioxide coating layer is formed through the coating treatment, and the surface of the photovoltaic glass is subjected to the post-treatment. The film layer is preliminarily cured through curing treatment, so that the surface cleanness of the glass and the completeness of the coating layer are ensured, and a good foundation is provided for toughening treatment; through partition temperature control of heating treatment and cooperation of a quartz roller transmission system and driving of a variable-frequency synchronous motor and a servo motor, it is guaranteed that glass passes through all heating areas at a constant speed, the heating process is uniform and stable, meanwhile, a high-pressure air grid system is adopted for cooling treatment for quenching, air grid parameters are controlled, and cooling rate matching is guaranteed; and defects caused by uneven stress distribution are avoided.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic glass processing technology, specifically to a tempering process for high-strength 2.0mm coated photovoltaic glass. Background Technology

[0002] Photovoltaic glass is a special type of glass used in solar photovoltaic modules. It is mainly divided into two categories: crystalline silicon photovoltaic glass and thin-film photovoltaic glass. It is used in building photovoltaic integration fields such as solar smart windows and photovoltaic curtain walls. Its mainstream products include ultra-clear rolled glass and AR coated glass, which need to have high light transmittance and weather resistance to protect photovoltaic cells.

[0003] Currently, in the tempering process of coated photovoltaic glass with a thickness of 2.0 mm or less, due to the thinness of the glass itself and the presence of a coating layer on the surface, the traditional tempering process is prone to uneven temperature control or insufficient transmission stability during the heating and cooling stages. This can lead to thermal stress deformation of the glass or a mismatch in cooling rates, which in turn can cause problems such as optical distortion, stress spots, or even dark cracks on the glass surface. It is impossible to guarantee that the coated photovoltaic glass can maintain its excellent optical performance and surface quality while achieving high strength.

[0004] Therefore, a tempering process for high-strength 2.0mm coated photovoltaic glass is proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a tempering process for high-strength 2.0mm coated photovoltaic glass, which solves the problem mentioned in the background technology of glass deformation due to thermal stress or mismatch in cooling rate, which leads to optical distortion, stress spots, or even dark cracks on the glass surface.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a tempering process for high-strength 2.0mm coated photovoltaic glass, comprising the following steps:

[0007] Step 1: Cleaning process. Select a sheet of photovoltaic glass with a thickness of 1.85mm-2.15mm, clean and dry it to remove surface impurities and moisture.

[0008] Step 2: Coating treatment. The cleaned glass is coated with a coating solution prepared by sol-gel method. The temperature in the coating room is controlled at 20-25℃, the humidity at 50-55%, the main pump speed at 90-110 rpm, the auxiliary pump speed at 40-60 rpm, the replenishment pump speed at 40-44 rpm, the roller speed at 12.8-13.5 m / min, and the conveying speed at 10-20 m / min, forming a nano-porous silica coating layer.

[0009] Step 3: Curing treatment. The coated glass is cured at a temperature of 150-250℃ and the curing oven is 15m long.

[0010] Step 4: Tempering treatment, which involves tempering the cured glass, including the following sub-steps:

[0011] I. Heat treatment: The pretreated glass is heated in a heating zone using a quartz roller drive system. The quartz rollers have a diameter of Φ50-60mm. The heating zone is divided into eight zones, numbered from zone 1 to zone 8 from the inlet to the outlet. The roller spacing between the quartz rollers in zones 1 and 2 is 180-220mm, in zone 3 it is 140-180mm, in zone 4 it is 100-140mm, in zone 5 it is 80-120mm, in zone 6 it is 70-110mm, and in zones 7 and 8 it is 60-80mm. The main drive of the quartz roller drive system is driven by a variable frequency synchronous motor, and the acceleration section after exiting the furnace is driven by a servo motor to control the glass conveying speed.

[0012] II. Cooling treatment: The heated glass is quenched using a high-pressure air grid system. The high-pressure air grid has a pressure resistance of over 100 kPa and a length of 1800-2200 mm. The rapid lifting speed of the air grid during quenching is 10-15 mm / s. The high-pressure air grid system is driven by a high-pressure fan with a power of 400-500 kW.

[0013] Step 5: Post-processing to obtain high-strength tempered photovoltaic glass, followed by surface quality inspection and packaging.

[0014] Preferably, in step one, the cleaning process includes the following steps:

[0015] The original photovoltaic glass is placed in a cleaning device for immersion. During the immersion process, an ultrasonic cleaner is used to assist in cleaning at a frequency of 40-60kHz. After immersion, it is taken out and rinsed with deionized water for 3-5 minutes.

[0016] Preferably, in step four, the temperature of the heating zone is controlled during the heating process. The temperature of the first and second zones is set to 300-400℃, the temperature of the third and fourth zones is set to 400-500℃, the temperature of the fifth and sixth zones is set to 500-600℃, and the temperature of the seventh and eighth zones is set to 600-700℃. The total residence time of the glass in the heating zone is 1-5 minutes. The glass conveying speed is controlled by a variable frequency synchronous motor and a servo motor to make the glass pass through each heating zone at a uniform speed of 10-20cm / s.

[0017] Preferably, in step four, the main drive shaft of the quartz roller drive system has a diameter greater than 50mm, is made of high-strength stainless steel, and is connected to the quartz roller by gears. The transmission accuracy error is less than ±0.1mm, and the power of the main drive variable frequency synchronous motor is 15-20kW, and the power of the servo motor is 5-10kW.

[0018] Preferably, in step four, the heating zone is also equipped with a temperature sensor and a feedback control system. The temperature sensor adopts a K-type thermocouple to monitor the temperature of each zone in real time. The feedback control system dynamically adjusts the heating power according to the temperature data, and the temperature fluctuation range is controlled within ±5℃. The glass is heated to the tempering temperature of 700℃±10℃.

[0019] Preferably, in step four, the closing accuracy of the high-pressure air grid is ±0.2mm, the distance between the air nozzles is 10-15mm, the adjustable air pressure range is 50-100kPa, the distance between the air grid and the glass surface during quenching is 5-10mm, and the lower part of the high-pressure air grid section is provided with an exhaust channel with an exhaust velocity of 5-10m / s.

[0020] Preferably, in step four, the high-pressure blower is driven by two 560kW blowers in parallel, the speed of the blower motor is 1500-3000r / min, the air volume is adjustable in the range of 10000-20000m³ / h, and the blower inlet is equipped with a filter screen with a filtration accuracy of 10μm.

[0021] Preferably, step four further includes cooling the air inlet of the high-pressure blower, specifically by installing a spiral cooling pipe at the air inlet of the blower, and circulating cold water in the cooling pipe. The cold water temperature is 5-15℃ and the flow rate is 10-20L / min, so that the air inlet temperature is controlled below 30℃.

[0022] Preferably, in step four, the roller spacing of the high-pressure air grid section is 60-80mm, the roller material is ceramic-coated steel roller, the roller surface smoothness Ra≤0.1μm, reducing frictional damage to the glass surface, and the roller is driven by an independent motor with a rotation speed synchronized with the main drive.

[0023] Preferably, in step five, the post-processing includes impact resistance testing, light transmittance testing, and thickness measurement of the tempered glass. The impact resistance test adopts the falling ball method, with a steel ball weight of 535g and a drop of 1m. The light transmittance requirement is greater than 91%, and the thickness tolerance is ±0.1mm. Qualified products are then wrapped and packaged.

[0024] Compared with the prior art, the present invention provides a tempering process for high-strength 2.0mm coated photovoltaic glass, which has the following beneficial effects:

[0025] 1. In this invention, during the tempering process of high-strength 2.0mm coated photovoltaic glass, a cleaning process is used to ensure the removal of surface impurities and moisture. At the same time, a nano-porous silica coating layer is formed by the coating process, and a curing process is used to initially solidify the coating layer, ensuring the cleanliness of the glass surface and the integrity of the coating layer, thus providing a good foundation for the tempering process.

[0026] 2. In this invention, during the tempering process, the glass passes through each heating zone at a uniform speed by means of zoned temperature control of the heating process and the quartz roller transmission system in conjunction with the variable frequency synchronous motor and servo motor drive, so that the heating process is uniform and stable. At the same time, the cooling process adopts a high-pressure air grid system for quenching and controls the air grid parameters to ensure matching cooling rate and avoid defects caused by thermal stress deformation.

[0027] 3. In this invention, during post-processing, surface quality inspection and packaging, including impact resistance testing, light transmittance testing, and thickness measurement, ensure the impact resistance, light transmittance requirements, and thickness tolerance of the tempered glass, thereby guaranteeing product qualification and quality reliability and improving the overall performance of photovoltaic glass. Attached Figure Description

[0028] Figure 1 This is a flowchart of the tempering process for a high-strength 2.0mm coated photovoltaic glass according to the present invention. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1: Please refer to Figure 1 A tempering process for high-strength 2.0mm coated photovoltaic glass includes the following steps:

[0031] Step 1: Cleaning process. Select a 1.85mm thick original photovoltaic glass sheet, clean and dry it to remove surface impurities and moisture;

[0032] Step 2: Coating treatment. The cleaned glass is coated with a coating solution using the sol-gel method. The temperature in the coating room is controlled at 20℃ and the humidity at 50%. The main pump speed is 90 rpm, the auxiliary pump speed is 40 rpm, the replenishment pump speed is 40 rpm, the rubber roller speed is 12.8 m / min, and the conveying speed is 10 m / min, forming a nano-porous silica coating layer.

[0033] Step 3: Curing treatment. The coated glass is cured in a curing oven at 150°C and 15m in length.

[0034] Step 4: Tempering treatment, which involves tempering the cured glass, including the following sub-steps:

[0035] I. Heat treatment: The pretreated glass is heated in a heating zone using a quartz roller drive system. The quartz rollers have a diameter of Φ50mm. The heating zone is divided into eight zones, numbered from zone 1 to zone 8 from the inlet to the outlet. The roller spacing between the quartz rollers in zones 1 and 2 is 180mm, in zone 3 it is 140mm, in zone 4 it is 100mm, in zone 5 it is 80mm, in zone 6 it is 70mm, and in zones 7 and 8 it is 60mm. The main drive of the quartz roller drive system is driven by a variable frequency synchronous motor, and the acceleration section after exiting the furnace is driven by a servo motor to control the glass conveying speed.

[0036] II. Cooling treatment: The heated glass is quenched using a high-pressure air grid system. The high-pressure air grid has a pressure resistance of over 100 kPa and a length of 1800 mm. The rapid lifting speed of the air grid during quenching is 10 mm / s. The high-pressure air grid system is driven by a high-pressure fan with a power of 400 kW.

[0037] Step 5: Post-processing to obtain high-strength tempered photovoltaic glass, followed by surface quality inspection and packaging.

[0038] Step one, the cleaning process includes the following steps:

[0039] The original photovoltaic glass was placed in a cleaning device for immersion. During the immersion process, an ultrasonic cleaner was used to assist in cleaning at a frequency of 40kHz. After immersion, the glass was removed and rinsed with deionized water for 3 minutes.

[0040] In step four, the temperature of the heating zone is controlled during the heating process. The temperature of the first and second zones is set to 300℃, the temperature of the third and fourth zones is set to 400℃, the temperature of the fifth and sixth zones is set to 500℃, and the temperature of the seventh and eighth zones is set to 600℃. The total residence time of the glass in the heating zone is 1 minute. The glass conveying speed is controlled by the frequency conversion synchronous motor and the servo motor to make the glass pass through each heating zone at a uniform speed of 10cm / s.

[0041] In step four, the main drive shaft of the quartz roller drive system has a diameter greater than 50mm and is made of high-strength stainless steel. The drive shaft and the quartz roller are connected by gears, and the transmission accuracy error is less than ±0.1mm. The main drive variable frequency synchronous motor has a power of 15kW, and the servo motor has a power of 5kW.

[0042] In step four, the heating zone is also equipped with a temperature sensor and a feedback control system. The temperature sensor uses a K-type thermocouple to monitor the temperature of each zone in real time. The feedback control system dynamically adjusts the heating power based on the temperature data, and the temperature fluctuation range is controlled within ±5℃. The glass is heated to the tempering temperature of 690℃.

[0043] In step four, the closure accuracy of the high-pressure air grid is ±0.2mm, the nozzle spacing is 10mm, the air pressure is adjustable to 50kPa, the distance between the air grid and the glass surface during quenching is 5mm, and the lower part of the high-pressure air grid section is equipped with an exhaust channel with an exhaust speed of 5m / s to quickly remove hot air and avoid secondary heating of the glass.

[0044] In step four, the high-pressure blower is driven by two 560kW blowers in parallel. The blower motor speed is 1500r / min, the air volume is adjustable to 10000m³ / h, and the blower inlet is equipped with a filter screen with a filtration accuracy of 10μm.

[0045] Step four also includes cooling the air inlet of the high-pressure blower. Specifically, a spiral cooling pipe is installed at the air inlet of the blower, and cold water is circulated in the cooling pipe. The cold water temperature is 5°C and the flow rate is 10L / min, so that the air inlet temperature is controlled below 30°C to avoid the air temperature rising and affecting the quenching effect.

[0046] In step four, the roller spacing of the high-pressure air grid section is 60mm, the roller material is ceramic-coated steel roller, the roller surface smoothness Ra≤0.1μm, reducing frictional damage to the glass surface, and the roller is driven by an independent motor with a speed synchronized with the main drive.

[0047] In step five, post-processing includes impact resistance testing, light transmittance testing, and thickness measurement of the tempered glass. The impact resistance test uses the falling ball method, with a steel ball weighing 535g and a drop of 1m. The light transmittance requirement is greater than 91%, and the thickness tolerance is ±0.1mm. Qualified products are then wrapped and packaged.

[0048] In the post-processing stage of step five, three key performance tests need to be performed on the tempered high-strength 2.0mm coated photovoltaic glass. The specific implementation steps are as follows:

[0049] First, an impact resistance test is carried out. This method uses the falling ball method to scientifically quantify the mechanical strength of glass. The specific operation is as follows: Randomly select at least three tempered glass samples with complete specifications from the same production batch, place them horizontally on a standard test bench. This bench is composed of a rigid circular support ring with an inner diameter of 495 mm and an outer edge height not less than 100 mm, ensuring that the glass samples are stably supported and suspended on all sides. The test environment needs to be controlled at a room temperature of 18 °C. Use a quenched steel ball with a total mass of 495 g and a smooth and flawless surface as the impact body, and let it freely fall from a height of 990 mm directly above the center point of the upper surface of the glass through a vertical guide tube to impact the glass sample. Each sample only withstands one impact. After the impact, carefully check the surface and interior of the glass. If the sample does not crack, break, or only produces fine cracks but does not penetrate completely, it is determined that its impact resistance performance is qualified.

[0050] Secondly, the light transmittance detection is carried out to evaluate the influence of the tempering process on the optical properties of the glass. Use a calibrated ultraviolet-visible spectrophotometer as the detection instrument. Cut or select a representative flat area from the glass to be tested as the specimen, ensuring that the surface is clean and scratch-free. Place the specimen vertically in the sample optical path of the instrument, and select light with a wavelength of 550 nm as the detection light source because this wavelength is close to the visible light region most sensitive to the human eye and can characterize the overall light transmittance performance of the glass. First, perform baseline calibration in the instrument, and then measure the intensity of the light after passing through the specimen. The instrument will automatically calculate and display the light transmittance value of the specimen at a wavelength of 550 nm. Repeat the measurement three times, and take the arithmetic mean as the final result. The present invention requires that the average light transmittance of the finished tempered glass is greater than 91% to ensure that it can capture solar energy to the maximum extent when used in photovoltaic modules.

[0051] Finally, the thickness measurement is carried out to control the consistency and uniformity of the product size. Use an electronic digital micrometer with a precision not less than 0.01 mm as the measurement tool. Measure at a total of five predetermined positions, namely the midpoints of the four edges and the center point of each glass sample. During the measurement, ensure that the measuring surface of the micrometer is perpendicular to the glass surface and in stable contact, apply a constant and moderate force, and record the value after the reading is stable. Calculate the average value of these five measurement values as the average thickness of the glass block, and calculate the difference between the maximum value and the minimum value to evaluate the thickness uniformity. The present invention requires that the average thickness tolerance of the finished tempered glass is strictly controlled within ±0.1 mm, and the thickness range difference of the same glass block shall not exceed this range either, to ensure its matching and reliability in the subsequent component lamination process.

[0052] Example 2: Please refer to Figure 1 : A tempering process for high-strength 2.0 mm coated photovoltaic glass, including the following steps:

[0053] Step 1: Cleaning process. Select a 2.0mm thick original photovoltaic glass sheet, clean and dry it to remove surface impurities and moisture.

[0054] Step 2: Coating treatment. The cleaned glass is coated with a coating solution using the sol-gel method. The temperature in the coating room is controlled at 23°C and the humidity at 53%. The main pump speed is 100 rpm, the auxiliary pump speed is 50 rpm, the replenishment pump speed is 42 rpm, the rubber roller speed is 13.1 m / min, and the conveying speed is 15 m / min, forming a nano-porous silica coating layer.

[0055] Step 3: Curing treatment. The coated glass is cured in a curing oven at 200℃ and 15m in length.

[0056] Step 4: Tempering treatment, which involves tempering the cured glass, including the following sub-steps:

[0057] I. Heat treatment: The pretreated glass is heated in a heating zone using a quartz roller drive system. The quartz rollers have a diameter of Φ55mm. The heating zone is divided into eight zones, numbered from zone 1 to zone 8 from the inlet to the outlet. The roller spacing between the quartz rollers in zones 1 and 2 is 200mm, in zone 3 it is 160mm, in zone 4 it is 120mm, in zone 5 it is 100mm, in zone 6 it is 90mm, and in zones 7 and 8 it is 70mm. The main drive of the quartz roller drive system is driven by a variable frequency synchronous motor, and the acceleration section after exiting the furnace is driven by a servo motor to control the glass conveying speed.

[0058] II. Cooling treatment: The heated glass is quenched using a high-pressure air grid system. The high-pressure air grid has a pressure resistance of over 100 kPa and a length of 2000 mm. The rapid lifting speed of the air grid during quenching is 12.5 mm / s. The high-pressure air grid system is driven by a high-pressure fan with a power of 450 kW.

[0059] Step 5: Post-processing to obtain high-strength tempered photovoltaic glass, followed by surface quality inspection and packaging.

[0060] Step one, the cleaning process includes the following steps:

[0061] The original photovoltaic glass was placed in a cleaning device for immersion. During the immersion process, an ultrasonic cleaner was used to assist in cleaning at a frequency of 50kHz. After immersion, the glass was removed and rinsed with deionized water for 4 minutes.

[0062] In step four, the temperature of the heating zone is controlled during the heating process. The temperature of the first and second zones is set to 350℃, the temperature of the third and fourth zones is set to 450℃, the temperature of the fifth and sixth zones is set to 550℃, and the temperature of the seventh and eighth zones is set to 6850℃. The total residence time of the glass in the heating zone is 3 minutes. The glass conveying speed is controlled by a variable frequency synchronous motor and a servo motor to make the glass pass through each heating zone at a uniform speed of 15cm / s.

[0063] In step four, the main drive shaft of the quartz roller drive system has a diameter greater than 50mm and is made of high-strength stainless steel. The drive shaft and the quartz roller are connected by gears, and the transmission accuracy error is less than ±0.1mm. The main drive variable frequency synchronous motor has a power of 18kW, and the servo motor has a power of 8kW.

[0064] In step four, the heating zone is also equipped with a temperature sensor and a feedback control system. The temperature sensor uses a K-type thermocouple to monitor the temperature of each zone in real time. The feedback control system dynamically adjusts the heating power based on the temperature data, and the temperature fluctuation range is controlled within ±5℃. The glass is heated to the tempering temperature of 700℃.

[0065] In step four, the closing accuracy of the high-pressure air grid is ±0.2mm, the distance between the air nozzles is 13mm, the air pressure is adjustable to 85kPa, the distance between the air grid and the glass surface during quenching is 7.5mm, and the lower part of the high-pressure air grid section is equipped with an exhaust channel with an exhaust speed of 7.5m / s to quickly remove hot air and avoid secondary heating of the glass.

[0066] In step four, the high-pressure blower is driven by two 560kW blowers in parallel. The speed of the blower motor is 2250r / min, the air volume is adjustable to 15000m³ / h, and the blower inlet is equipped with a filter screen with a filtration accuracy of 10μm.

[0067] Step four also includes cooling the air inlet of the high-pressure blower. Specifically, a spiral cooling pipe is installed at the air inlet of the blower, and cold water is circulated in the cooling pipe. The cold water temperature is 10℃ and the flow rate is 15L / min, so that the air inlet temperature is controlled below 30℃ to avoid the air temperature rising and affecting the quenching effect.

[0068] In step four, the roller spacing of the high-pressure air grid section is 70mm, the roller material is ceramic-coated steel roller, the roller surface smoothness Ra≤0.1μm, reducing frictional damage to the glass surface, and the roller is driven by an independent motor with a speed synchronized with the main drive.

[0069] In step five, post-processing includes impact resistance testing, light transmittance testing, and thickness measurement of the tempered glass. The impact resistance test uses the falling ball method, with a steel ball weighing 535g and a drop of 1m. The light transmittance requirement is greater than 91%, and the thickness tolerance is ±0.1mm. Qualified products are then wrapped and packaged.

[0070] In the post - processing stage of Step Five, three key performance inspections need to be carried out on the tempered high - strength 2.0 - mm coated photovoltaic glass. The specific implementation steps are as follows:

[0071] First, perform the impact resistance test. This method uses the falling ball method to scientifically quantify the mechanical strength of the glass. The specific operation is as follows: Randomly select at least three tempered glass samples with complete specifications from the same production batch, place them horizontally on a standard - compliant test bench. The test bench consists of a rigid circular support ring with an inner diameter of 500 mm and an outer edge height not less than 100 mm, ensuring that the glass samples are stably supported and suspended on all sides. The test environment needs to be controlled at room temperature of 23 °C. Use a quenched steel ball with a total mass of 500 g and a smooth and flawless surface as the impact body. Let it freely fall from a height of 1000 mm directly above the center point of the upper surface of the glass through a vertical guiding tube to impact the glass sample. Each sample only undergoes one impact. After the impact, carefully check the surface and interior of the glass. If the sample does not crack, break, or only has fine cracks but is not completely penetrated, it is determined that its impact resistance performance is qualified.

[0072] Secondly, perform the light transmittance detection to evaluate the influence of the tempering process on the optical properties of the glass. Use a calibrated ultraviolet - visible spectrophotometer as the detection instrument. Cut or select a representative flat area from the glass to be tested as the specimen, ensuring that the surface is clean and scratch - free. Place the specimen vertically in the sample optical path of the instrument. Select light with a wavelength of 550 nm as the detection light source because this wavelength is close to the most sensitive visible light region of the human eye and can characterize the overall light transmittance performance of the glass. First, perform baseline calibration in the instrument, and then measure the intensity of the light after passing through the specimen. The instrument will automatically calculate and display the light transmittance value of the specimen at a wavelength of 550 nm. Repeat the measurement three times and take the arithmetic mean as the final result. The present invention requires that the average light transmittance of the finished tempered glass is greater than 91% to ensure that it can capture solar energy to the maximum extent when used in photovoltaic modules.

[0073] Finally, perform thickness measurement to control the consistency and uniformity of the product size. Use an electronic digital micrometer with a precision of not less than 0.01 mm as the measurement tool. Measure at a total of five predetermined positions, namely the mid - points of the four edges and the center point of each glass sample. During the measurement, ensure that the measuring surface of the micrometer is perpendicular to the glass surface and makes stable contact, apply a constant and moderate force, and record the value after the reading is stable. Calculate the average value of these five measurement values as the average thickness of the glass block, and calculate the difference between the maximum value and the minimum value to evaluate the thickness uniformity. The present invention requires that the average thickness tolerance of the finished tempered glass is strictly controlled within ±0.1 mm, and the thickness range of the same glass block shall not exceed this range either, to ensure its compatibility and reliability in the subsequent component lamination process.

[0074] Example 3: Please refer to Figure 1 A tempering process for high-strength 2.0mm coated photovoltaic glass includes the following steps:

[0075] Step 1: Cleaning process. Select a 2.15mm thick photovoltaic glass sheet, clean and dry it to remove surface impurities and moisture.

[0076] Step 2: Coating treatment. The cleaned glass is coated with a coating solution using the sol-gel method. The temperature in the coating room is controlled at 25°C and the humidity at 55%. The main pump speed is 110 rpm, the auxiliary pump speed is 60 rpm, the replenishment pump speed is 44 rpm, the rubber roller speed is 13.5 m / min, and the conveying speed is 20 m / min, forming a nano-porous silica coating layer.

[0077] Step 3: Curing treatment. The coated glass is cured in a curing oven at 250℃ and 15m in length.

[0078] Step 4: Tempering treatment, which involves tempering the cured glass, including the following sub-steps:

[0079] I. Heat treatment: The pretreated glass is heated in a heating zone using a quartz roller drive system. The quartz rollers have a diameter of Φ60mm. The heating zone is divided into eight zones, numbered from zone 1 to zone 8 from the inlet to the outlet. The roller spacing between the quartz rollers in zones 1 and 2 is 220mm, in zone 3 it is 180mm, in zone 4 it is 140mm, in zone 5 it is 120mm, in zone 6 it is 110mm, and in zones 7 and 8 it is 80mm. The main drive of the quartz roller drive system is driven by a variable frequency synchronous motor, and the acceleration section after exiting the furnace is driven by a servo motor to control the glass conveying speed.

[0080] II. Cooling treatment: The heated glass is quenched using a high-pressure air grid system. The high-pressure air grid has a pressure resistance of over 100 kPa and a length of 2200 mm. The rapid lifting speed of the air grid during quenching is 15 mm / s. The high-pressure air grid system is driven by a 500 kW high-pressure fan.

[0081] Step 5: Post-processing to obtain high-strength tempered photovoltaic glass, followed by surface quality inspection and packaging.

[0082] Step one, the cleaning process includes the following steps:

[0083] The original photovoltaic glass was placed in a cleaning device for immersion. During the immersion process, an ultrasonic cleaner was used to assist in cleaning at a frequency of 60kHz. After immersion, the glass was removed and rinsed with deionized water for 5 minutes.

[0084] In step four, the temperature of the heating zone is controlled during the heat treatment. The temperature of the first and second zones is set to 400℃, the temperature of the third and fourth zones is set to 500℃, the temperature of the fifth and sixth zones is set to 600℃, and the temperature of the seventh and eighth zones is set to 700℃. The total residence time of the glass in the heating zone is 5 minutes. The glass conveying speed is controlled by the frequency conversion synchronous motor and the servo motor to make the glass pass through each heating zone at a uniform speed of 20cm / s.

[0085] In step four, the main drive shaft of the quartz roller drive system has a diameter greater than 50mm and is made of high-strength stainless steel. The drive shaft and the quartz roller are connected by gears, and the transmission accuracy error is less than ±0.1mm. The main drive variable frequency synchronous motor has a power of 20kW, and the servo motor has a power of 10kW.

[0086] In step four, the heating zone is also equipped with a temperature sensor and a feedback control system. The temperature sensor uses a K-type thermocouple to monitor the temperature of each zone in real time. The feedback control system dynamically adjusts the heating power based on the temperature data, and the temperature fluctuation range is controlled within ±5℃. The glass is heated to the tempering temperature of 710℃.

[0087] In step four, the closing accuracy of the high-pressure air grid is ±0.2mm, the nozzle spacing is 15mm, the air pressure is adjustable to 100kPa, the distance between the air grid and the glass surface during quenching is 10mm, and the lower part of the high-pressure air grid section is equipped with an exhaust channel with an exhaust speed of 10m / s to quickly remove hot air and avoid secondary heating of the glass.

[0088] In step four, the high-pressure blower is driven by two 560kW blowers in parallel. The blower motor speed is 3000r / min, the air volume is adjustable to 20000m³ / h, and the blower inlet is equipped with a filter screen with a filtration accuracy of 10μm.

[0089] Step four also includes cooling the air inlet of the high-pressure blower. Specifically, a spiral cooling pipe is installed at the air inlet of the blower, and cold water is circulated in the cooling pipe. The cold water temperature is 15℃ and the flow rate is 20L / min, so that the air inlet temperature is controlled below 30℃ to avoid the air temperature rising and affecting the quenching effect.

[0090] In step four, the roller spacing of the high-pressure air grid section is 80mm, the roller material is ceramic-coated steel roller, the roller surface smoothness Ra≤0.1μm, reducing frictional damage to the glass surface, and the roller is driven by an independent motor with a speed synchronized with the main drive.

[0091] In Step 5, the post-treatment includes impact resistance testing, light transmittance detection, and thickness measurement of the tempered glass. The impact resistance test uses the falling ball method. The steel ball weighs 535 g and the drop height is 1 m. The light transmittance requirement is greater than 91%, and the thickness tolerance is ±0.1 mm. Qualified products are subjected to film laminating and packaging.

[0092] In the post-treatment stage of Step 5, three key performance inspections need to be carried out on the completed tempered 2.0 mm coated photovoltaic glass. The specific implementation steps are as follows:

[0093] First, conduct the impact resistance test. This method uses the falling ball method to scientifically quantify the mechanical strength of the glass. The specific operation is as follows: Randomly select at least three tempered glass samples with complete specifications from the same production batch and place them horizontally on a standard test bench. The test bench consists of a rigid circular support ring with an inner diameter of 505 mm and an outer edge height not less than 100 mm, ensuring that the glass samples are stably supported and suspended on all sides. The test environment needs to be controlled at a room temperature of 28°C. Use a quenched steel ball with a total mass of 505 g and a smooth and flawless surface as the impact body, and let it freely fall from a height of 1010 mm directly above the center point of the upper surface of the glass through a vertical guide tube to impact the glass sample. Each sample only withstands one impact. After the impact, carefully check the surface and interior of the glass. If the sample does not crack, shatter, or only produces fine cracks but does not penetrate completely, it is determined that its impact resistance performance is qualified.

[0094] Second, conduct the light transmittance detection to evaluate the impact of the tempering process on the optical properties of the glass. Use a calibrated ultraviolet-visible spectrophotometer as the detection instrument. Cut or select a representative flat area from the glass to be tested as the specimen, ensuring that the surface is clean and scratch-free. Place the specimen vertically in the sample optical path of the instrument and select light with a wavelength of 550 nm as the detection light source because this wavelength is close to the visible light region most sensitive to the human eye and can characterize the overall light transmittance performance of the glass. First, perform baseline calibration in the instrument, and then measure the intensity of the light after passing through the specimen. The instrument will automatically calculate and display the light transmittance value of the specimen at a wavelength of 550 nm. Repeat the measurement three times and take the arithmetic mean as the final result. The present invention requires that the average light transmittance of the finished tempered glass is greater than 91% to ensure that it can capture solar energy to the maximum extent when used in photovoltaic modules.

[0095] Finally, thickness measurements are performed to control the consistency and uniformity of product dimensions. An electronic digital micrometer with an accuracy of at least 0.01 mm is used as the measuring tool. Measurements are taken at five predetermined locations: the midpoints of the four edges and the center point of each glass sample. During measurement, the measuring surface of the micrometer is ensured to be perpendicular to the glass surface and in stable contact, with a constant and moderate force applied. The values ​​are recorded after the readings stabilize. The average of these five measurements is calculated as the average thickness of the glass sample, and the difference between the maximum and minimum values ​​is calculated to assess thickness uniformity. This invention requires that the average thickness tolerance of the finished tempered glass be strictly controlled within ±0.1 mm, and the thickness difference within the same piece of glass must not exceed this range to ensure its compatibility and reliability in subsequent component lamination processes.

[0096] Comparative Example 1: The difference between this comparative example and Example 1 is that this comparative example did not use an ultrasonic cleaner to assist in the cleaning process.

[0097] Comparative Example 2 differs from Example 1 in that the temperature in this comparative example is not controlled by zone during the heating process, and all heating zones are set to a uniform temperature of 500°C.

[0098] Comparative Example 3 differs from Example 1 in that the rapid descent speed of the air grating was not controlled during the cooling process in this comparative example, and the air grating was kept in a fixed position.

[0099] Comparative Example 4 differs from Example 1 in that the air inlet of the high-pressure blower was not cooled in this comparative example.

[0100] The tempering process of the high-strength 2.0mm coated photovoltaic glass prepared in Examples 1-3 and Comparative Examples 1-4 was tested for performance. The test items and methods are as follows:

[0101] Impact resistance test: The falling ball method was used. The steel ball weighed 535g and dropped 1m. The sample was placed horizontally and checked for breakage after impact.

[0102] Transmittance was tested using a UV-Vis spectrophotometer at a wavelength of 550 nm, and the percentage was calculated.

[0103] Thickness measurement is performed using an electronic digital micrometer to measure the glass thickness at five points, calculate the average thickness and thickness range, and require a tolerance of ±0.1mm.

[0104] Bending strength testing was conducted using the three-point bending method with a universal testing machine. The sample size was 100mm × 100mm, the distance between the support points was 80mm, and the loading speed was 10mm / min. The fracture strength was then measured.

[0105] The test data of the high-strength 2.0 mm coated photovoltaic glasses prepared in Examples 1-3 and Comparative Examples 1-4 are recorded in the table below:

[0106] Group Impact resistance test (whether it breaks) Light transmittance (%) Thickness tolerance (mm) Bending strength (MPa) Example 1 Unbroken 92.5 ±0.05 185 Example 2 Unbroken 93.0 ±0.06 190 Example 3 Unbroken 92.8 ±0.04 188 Comparative Example 1 rupture 89.5 ±0.15 150 Comparative Example 2 rupture 88.0 ±0.20 140 Comparative Example 3 rupture 90.0 ±0.18 145 Comparative Example 4 rupture 89.8 ±0.16 148

[0107] By comparing and analyzing the data in the table, it can be seen that the high-strength 2.0mm coated photovoltaic glass prepared using the processes in Examples 1-3 exhibits significantly superior performance compared to the photovoltaic glass prepared using the processes in Comparative Examples 1-4. This indicates that the present invention ensures the removal of surface impurities and moisture through cleaning, while the coating process forms a nano-porous silica coating layer. The curing process initially solidifies the film layer, ensuring the cleanliness of the glass surface and the integrity of the coating layer, providing a good foundation for tempering. During tempering, the zoned temperature control of the heating process and the quartz roller drive system, combined with the variable frequency synchronous motor and servo motor drive, ensure that the glass passes through each heating zone at a uniform speed, making the heating process uniform and stable. Simultaneously, the cooling process uses a high-pressure air grid system for quenching and controls the air grid parameters to ensure matching cooling rates and avoid defects caused by thermal stress deformation. In post-processing, surface quality inspection and packaging, including impact resistance testing, light transmittance testing, and thickness measurement, ensure the impact resistance, light transmittance requirements, and thickness tolerance of the tempered glass, guaranteeing product qualification and quality reliability, and improving the overall performance of the photovoltaic glass.

[0108] By comparing and analyzing the relevant data in the table, it can be seen that the high-strength 2.0mm coated photovoltaic glass prepared by the tempering process of this invention has good impact resistance, high light transmittance, dimensional stability, and high bending strength. This indicates that the tempering process for high-strength 2.0mm coated photovoltaic glass provided by this invention has a broader market prospect and is more suitable for widespread application.

[0109] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0110] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A process for tempering high strength 2.0 mm coated photovoltaic glass, characterized in that: It comprises the following steps: Step one: cleaning treatment, select the thickness of 1.85mm-2.15mm of the original piece of photovoltaic glass, clean and dry, remove surface impurities and moisture; Step two: coating treatment, the cleaned glass is coated, the coating solution is prepared by sol-gel method, the temperature between coating is controlled at 20-25℃, the humidity is 50-55%, the main pump speed is 90-110rpm, the auxiliary pump speed is 40-60rpm, the liquid supplement pump speed is 40-44rpm, the glue roller speed is 12.8-13.5m / min, the conveying speed is 10-20m / min, and the nano porous silica coating layer is formed; Step three: solidification treatment, the coated glass is solidified, the solidification furnace temperature is 150-250℃, and the solidification furnace length is 15m; Step four: tempering treatment, the solidified glass is tempered, which comprises the following substeps: Ⅰ, heating treatment, the pretreated glass is heated through the heating zone, the quartz roller transmission system is used, the main transmission of the quartz roller transmission system is driven by a variable frequency synchronous motor, the servo motor is used to drive the acceleration section of the furnace outlet, and the glass conveying speed is controlled; Ⅱ, cooling treatment, the heated glass is quenched by using a high-pressure air grid system, the high-pressure air grid system has a pressure of more than 100kPa, the air grid length is 1800-2200mm, the rapid lifting speed of the air grid during quenching is 10-15mm / s, and the high-pressure air grid system is driven by a high-pressure fan with a power of 400-500kW; Step five: post-treatment, high-strength tempered photovoltaic glass is obtained, and surface quality detection and packaging are carried out.

2. The process for tempering high strength 2.0 mm coated photovoltaic glass according to claim 1, characterized in that: In step one, the cleaning treatment comprises the following steps: The original piece of photovoltaic glass is placed in the cleaning device for soaking, and an ultrasonic cleaning machine is used to assist cleaning at a frequency of 40-60kHz during the soaking process, and after the soaking is completed, the glass is taken out and washed with deionized water for 3-5 minutes; Then it is placed in a hot air drying oven and dried at 50-60℃ for 1-3 minutes until the glass surface is completely dry.

3. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In step four, the temperature of the heating zone is controlled during the heating treatment, the temperature of the first and second zones is set to 300-400℃, the temperature of the third and fourth zones is set to 400-500℃, the temperature of the fifth and sixth zones is set to 500-600℃, and the temperature of the seventh and eighth zones is set to 600-700℃, the total residence time of the glass in the heating zone is 1-5 minutes, the glass conveying speed is controlled by the variable frequency synchronous motor and the servo motor, and the glass passes through each heating zone at a uniform speed of 10-20cm / s.

4. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In step four, the main transmission shaft of the quartz roller transmission system is greater than 50mm in diameter and is made of high-strength stainless steel, the transmission shaft and the quartz roller are connected by a gear, the transmission precision error is less than ±0.1mm, and the power of the main transmission variable frequency synchronous motor is 15-20kW, and the power of the servo motor is 5-10kW.

5. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In the fourth step, the heating zone is also provided with a temperature sensor and a feedback control system, the temperature sensor adopts a K-type thermocouple, real-time monitoring of the temperature of each zone, the feedback control system according to the temperature data dynamic adjustment of heating power, temperature fluctuation range is controlled within ±5℃, the glass is heated to the tempering temperature 700℃±10℃.

6. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In the fourth step, the closing accuracy of the high-pressure air grid is ±0.2mm, the air nozzle spacing is 10-15mm, the air pressure adjustable range is 50-100kPa, the distance between the air grid and the glass surface during quenching is 5-10mm, and the lower part of the high-pressure air grid section is provided with an air exhaust channel, and the air exhaust speed is 5-10m / s.

7. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the said process is characterized by: In the fourth step, the high-pressure fan adopts two fans with a power of 560kW in parallel driving, the speed of the fan motor is 1500-3000r / min, the air volume adjustable range is 10000-20000m³ / h, and the fan inlet is provided with a filter screen with a filtering accuracy of 10μm.

8. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In the fourth step, the high-pressure fan inlet is also cooled, specifically, a spiral cooling pipe is installed at the fan inlet, cold water is passed into the cooling pipe, the cold water temperature is 5-15℃, and the flow rate is 10-20L / min, so that the air inlet temperature is controlled below 30℃.

9. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In the fourth step, the roller spacing of the high-pressure air grid section is 60-80mm, the roller material is ceramic coated steel roller, the roller surface smoothness Ra≤0.1μm, the friction damage to the glass surface is reduced, and the roller is driven by an independent motor, and the speed is synchronized with the main drive.

10. The process for tempering high strength 2.0 mm coated photovoltaic glass as claimed in claim 1, wherein the process is characterized by: In the fifth step, the post-treatment includes impact resistance test, light transmittance detection and thickness measurement of the tempered glass, the impact resistance test adopts the falling ball method, the steel ball weight is 535g, the drop is 1m, the light transmittance requirement is greater than 91%, the thickness tolerance is ±0.1mm, and the qualified products are packaged with film.

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