An online multifunctional quality monitoring method and system for the casting process of fused refractory molten metal

Abstract

The present invention discloses an online multifunctional quality monitoring method and system for the casting process of molten refractory materials, which relates to the technical field of monitoring the casting process of molten refractory materials, including: determining the melting temperature, discharging temperature, casting temperature, and liquid temperature; a method and a quality monitoring method for determining the emissivity of the casting liquid; a parameter acquisition method and a quality monitoring method for monitoring the quality of the casting liquid; a parameter acquisition method and a quality monitoring method for monitoring the quality of the casting operation; a method and a quality monitoring method for calculating the solidification rate of the liquid; a method for evaluating the quality of the casting process; and a method for monitoring the rationality of the riser design. The above-mentioned scheme in the present invention utilizes a short-wave infrared thermal imager, a computer, and a remote monitoring system, which can accurately reflect the temperature and distribution of the casting system, accurately record the casting time, analyze the process quality of the casting process, and simultaneously perform on-site monitoring and remote monitoring, and can realize data playback analysis.

Description

Technical Field

[0001] The present invention relates to the technical field of monitoring the casting of molten refractory materials by electro-melting (also called fusion casting), and in particular to an online multifunctional quality monitoring method and system for the casting process of molten refractory materials by electro-melting. Background Art

[0002] In nature, any object with a temperature greater than absolute zero (-273°C) can radiate infrared rays. Infrared rays, together with visible light, ultraviolet rays, X-rays, gamma rays, cosmic rays and radio waves, constitute a complete and continuous electromagnetic spectrum. Its wavelength is between 0.78μm and 1000μm, which is invisible light with a longer wavelength than red light. Infrared rays are divided into near-infrared, short-wave infrared, medium-wave infrared and long-wave infrared according to the atmospheric window. A thermal imager converts the invisible infrared energy emitted by an object into a visible thermal image through an electrical signal. By viewing the thermal image, we can observe the overall temperature distribution of the target being measured, study the heating condition of the target, and provide a basis for judgment for work and research. Most of the thermal imagers we commonly use long-wave infrared for detection, which can be observed through the air but not through walls and glass. They also have the advantages of all-weather imaging, non-contact temperature measurement, and observation through smoke. However, with the continuous development of science and technology, shortwave thermal imagers have been widely used in many fields as a non-contact temperature measurement technology. It not only has the characteristics of non-contact, fast and accurate, but also can perform high-precision temperature measurement and imaging of targets in complex environments. Therefore, it has great application value in military, medical, industrial and other fields.

[0003] In the military field, shortwave thermal imagers can be used for night reconnaissance, target tracking, and fire control. Due to their high resolution and sensitivity, they can clearly identify enemy personnel and equipment, providing strong technical support for night operations. At the same time, shortwave thermal imagers can also be used in missile guidance, drone reconnaissance, and other fields to improve the accuracy and effectiveness of military operations.

[0004] In the medical field, shortwave thermal imagers can be used for early diagnosis and auxiliary treatment of diseases. For example, by detecting the temperature distribution on the human body surface, early symptoms of some diseases, such as inflammation and tumors, can be determined. In addition, shortwave thermal imagers can also be used to monitor changes in the patient's body temperature, providing doctors with accurate diagnosis and treatment plans.

[0005] In the industrial field, shortwave thermal imagers can be used for equipment status monitoring, fault diagnosis and quality control. For example, in the power industry, by detecting the temperature distribution of power equipment, potential faults and defects can be discovered in time to avoid accidents. In the manufacturing industry, shortwave thermal imagers can be used to detect product defects and quality problems to improve production efficiency and product quality.

[0006] With the rapid development of modern industrial technology, fused refractory materials are increasingly used in metallurgy, ceramics, glass and other fields, but the production cost is very high, mainly due to the following aspects:

[0007] The melting temperature of the liquid is high, and the energy consumption is high. Casting refractory materials often use high melting point materials such as alumina, zirconium oxide, zircon sand as the main raw materials, so the melting point is high, usually need to be melted to more than 2000℃, so the energy consumption is very high;

[0008] The utilization rate of liquid material is low and the cost is high. The molten liquid material needs to be poured into the sand mold for cooling. In order to ensure that the casting product has the required size, the sand mold size needs to be enlarged by about 1-2%. At the same time, in order to meet the need to replenish the liquid material during the cooling and shrinking process, the riser of the sand mold is usually designed to be one-third to one-half the volume of the brick mold. Therefore, the actual utilization rate of the liquid material is 30% to 50%. After the brick is cooled, the riser is cut off and crushed before it can be used as raw material in the next production cycle. In addition, due to the high hardness and strength of the material, it is difficult to crush, so the overall cost is greatly increased.

[0009] The technology is difficult and the qualified rate is low. Due to the large size of the brick, the liquid will shrink greatly during the cooling process from high temperature, so it is easy to produce cracks, shrinkage, shrinkage and poor organization. The brick is heavy, and it is very easy to bump into it during the transportation process, resulting in missing corners and edges. In addition, cracks and poor organization are the result of the combined effect of many process factors such as raw material ratio, material system, casting system, cooling speed, insulation material, insulation time, etc. in the process. The experimental study of the effect of a single factor is costly and not very accurate. Therefore, it is still the most technically advanced type of refractory material, and the qualified rate is usually around 80%, and even some varieties have a qualified rate of only about half. Therefore, precise control and reasonable arrangement of the process are extremely important.

[0010] As the core link of the production process of fused refractory materials, the quality monitoring of the molten metal casting process plays a vital role in the stability and safety of product performance. Factors such as casting temperature that is too high or too low, casting speed that is too fast or too slow, casting volume that is too large or too small, whether the casting position is accurate and reasonable, and the minimum riser size required for casting will affect the product qualification rate and production cost individually or even in combination. Therefore, the quality control of this process is the top priority of production process control. However, in the fused refractory industry, the handheld infrared thermometer currently used in the high-temperature molten metal casting process to monitor the casting temperature of the molten metal is a point temperature measuring device with an uncertain temperature measurement position. Since the molten metal temperature is as high as 1750℃-2300℃, and it will decrease as the furnace time increases during the casting process, the temperature of the molten metal is different at different times and different parts, and the temperature of the measuring point may not necessarily represent the temperature of the molten metal; the casting speed is calculated by manual stopwatch timing (accurate to seconds), and then the casting speed can be approximately calculated based on the casting volume. Different types and specifications of products require different casting temperatures and casting speeds to obtain qualified products. Therefore, temperature and time measurement, especially accurate temperature and time measurement, are very important for fused cast refractory materials. The development of an efficient, accurate and real-time automated online monitoring method has become an urgent need in the current field of electric fused refractory production.

[0011] At present, there are still some problems in the actual use of short-wave thermal imagers, such as the determination of the emissivity of the liquid to improve the temperature measurement accuracy, how to convert the surface scanning data cloud map into quality monitoring indicators for quality control, and the anti-interference ability. First of all, the temperature measurement accuracy is not only related to the configuration of the instrument itself, but also to the comprehensive effect of multiple factors such as the infrared emissivity of the liquid, exposure time, test distance, environmental conditions, etc. Therefore, optimizing the working parameters of the short-wave thermal imager and improving its temperature and time measurement accuracy, especially on this basis, developing new high-precision quality monitoring methods and indicators, is of great significance for expanding its application in the casting refractory industry and improving the overall level of product quality in the casting industry.

[0012] Therefore, the present invention is firstly devoted to solving the problem of accurate temperature and speed measurement, and secondly, it also assists in developing a variety of quality control methods and indicators during the temperature measurement process, so as to contribute to promoting the development of the fused casting refractory material industry. Summary of the invention

[0013] The purpose of the present invention is to provide an online multifunctional quality monitoring method and system for the casting process of fused refractory molten metal using a short-wave infrared thermal imager, a computer and a remote control platform, so as to accurately reflect the temperature and distribution of the casting system, accurately record the casting time, and realize on-site monitoring and remote monitoring at the same time.

[0014] To achieve the above object, the present invention provides the following solutions:

[0015] In a first aspect, the present invention provides an online multifunctional quality monitoring method for a molten refractory material casting process, comprising:

[0016] Determine the emissivity of the casting liquid;

[0017] Determine the temperature of the material;

[0018] Determine the discharge temperature;

[0019] Determine the casting temperature;

[0020] Monitor the quality of casting liquid;

[0021] Monitor the quality of casting operations;

[0022] Calculate the condensation rate of the liquid;

[0023] Judge the quality of the casting process;

[0024] Monitor the rationality of riser design.

[0025] Optionally, the step of determining the material temperature, the discharge temperature and the casting temperature specifically comprises the following steps:

[0026] During the casting process, the maximum temperature of the liquid is measured every 25 microseconds, which is the instantaneous maximum temperature;

[0027] Take the highest value of all instantaneous maximum temperature values ​​recorded during the casting process as the material temperature;

[0028] The temperature of the highest point of the liquid surface at the end of the furnace nozzle recorded during the casting process is used as the discharge temperature;

[0029] The instantaneous maximum temperature recorded during the casting process is averaged as the casting temperature;

[0030] The material temperature is a temperature data, and the instantaneous maximum temperature, discharge temperature and casting temperature are all dynamic data.

[0031] Optionally, determining the emissivity of the casting liquid specifically comprises the following steps:

[0032] According to the recorded temperature data at different emissivity, the emissivity-temperature function of the liquid is constructed;

[0033] Using the functional relationship measured at least five times, a function correction parameter is obtained according to the maximum temperature deviation and the minimum temperature deviation;

[0034] Correcting the emissivity-temperature function according to the function correction parameter to obtain a corrected emissivity-temperature function;

[0035] Based on the corrected emissivity-temperature function, the emissivity at the measured temperature is obtained.

[0036] Optionally, the monitoring of the quality of the casting liquid specifically includes:

[0037] Use the recorded images and videos to monitor the slurry's chemical temperature, discharge temperature, alarm temperature, casting temperature, slurry temperature at a certain point in the flow, the overall temperature uniformity of the slurry, and whether there are foreign objects in the slurry;

[0038] The specific quality monitoring method includes the following steps:

[0039] Set the maximum alarm temperature;

[0040] When the temperature in the monitored area reaches or exceeds the maximum alarm temperature, an alarm is issued;

[0041] When the liquid temperature in the monitoring area has a local regular low temperature area and flows with the liquid, it is determined that there are impurities in the liquid;

[0042] By analyzing the thermal imager images, the type of inclusions in the liquid can be determined;

[0043] And according to the quantity and type of debris, determine whether the box of products is qualified or whether to enter the next process;

[0044] When monitoring detects that nozzle material or sputtering cooling material blocks have fallen off in the liquid and entered the sand mold, the box number is marked for scrapping based on the size and quantity of the nozzle material blocks, or the size, quantity, falling position and time of the sputtering cooling material blocks. The thermal image is analyzed and judged to adjust the irregular operation to ensure the normal operation of the next furnace.

[0045] If the discharge temperature, chemical temperature or casting temperature is monitored to be too high and exceeds the upper limit of the discharge temperature set by the system, the casting speed needs to be reduced to make the temperature of the material liquid in the sand mold reach the normal range or the casting needs to be suspended;

[0046] If the discharge temperature, melting temperature or casting temperature is monitored to be low and exceeds the lower limit of the alarm temperature set by the system, it is necessary to stop casting and continue refining, and increase the current and voltage in the next melting or refining to ensure that the discharge temperature is within the normal range;

[0047] If the maximum instantaneous temperature of the liquid is higher than the maximum alarm temperature, the casting speed should be reduced so that the temperature of the liquid in the sand mold reaches the normal range, and the current and voltage should be reduced during the next batch of melting or refining to ensure that the maximum instantaneous temperature is within the normal range;

[0048] If the instantaneous maximum temperature of the liquid is monitored to be lower than the minimum alarm temperature, the casting should be stopped and the current and voltage should be increased during the next batch of melting or refining to ensure that the instantaneous maximum temperature is within the normal range;

[0049] If it is monitored that the instantaneous maximum temperature of the slurry fluctuates greatly, or the temperature of different parts of the slurry differs greatly, casting should be stopped, and refining should be continued until the slurry temperature is uniform before casting again.

[0050] Optionally, the type of inclusions in the slurry is determined by analyzing the thermal imager image, which specifically includes the following steps:

[0051] If there is an obvious large fixed-shape low-temperature area in the liquid material, it is judged that the furnace nozzle material has fallen off;

[0052] If there are scattered low-temperature small dots in the liquid that flow with the liquid, it is judged that the unmelted powder around the furnace has fallen;

[0053] If a large low-temperature area next to the inner wall of the sand mold rolls and sinks in the liquid, it is judged as a sputtering cooling block, that is, the liquid splashed onto the side wall is cooled and then swept away by the subsequent liquid;

[0054] If large flowing pieces or continuous irregular low-temperature areas are detected, it is judged that the liquid in the furnace is not uniform and the material operation needs to be improved;

[0055] If the temperature difference between the slurry and the liquid is large, or the temperature drops too quickly during the discharging process, resulting in excessive viscosity of the slurry, uneven boundary of the slurry flow stream, or dripping under the slurry, then the products in this box are judged to be scrapped products, and it is necessary to focus on verifying whether they are qualified in the later process. The next batch needs to extend the material dissolving time or take measures to reduce the temperature drop.

[0056] Optionally, monitoring the quality of the casting operation may include:

[0057] The data recorded by the monitoring thermal imager is processed to obtain the casting time, casting speed, casting position, amount of overflow after full pouring, number of supplementary pouring and number of exhaust times;

[0058] The casting duration is the casting time interval recorded by the video during the casting process;

[0059] The casting speed is obtained by dividing the casting amount by the casting time;

[0060] The casting position is a casting position determined according to process rules;

[0061] The amount of overflow after full pouring is the amount of material that is detected after cooling the overflowed material, and is used to calculate the material loss.

[0062] Specific methods for monitoring the quality of casting operations include:

[0063] When the casting speed is not within the preset speed range or the casting time is not within the preset time range, the box number is marked as to be scrapped and wait for the subsequent process to verify whether it is qualified;

[0064] If the amount of overflow after pouring exceeds the specified material loss, it is necessary to urge the improvement of the final casting speed;

[0065] If the monitoring records that the casting position deviates from the normal area, the box number should be marked for subsequent process inspection to see if the casting has defects;

[0066] Based on the monitoring records, determine whether the backfilling or exhaust is in compliance with the specifications and whether there are records of missing or excessive operations.

[0067] Optionally, the specific calculation method of the slurry coagulation rate includes:

[0068] Start timing and recording the temperature of the liquid surface in the sand box when casting is finished, and stop recording when the liquid surface solidifies;

[0069] The duration of the recording period divided by the temperature difference is the condensation rate of the slurry.

[0070] Optionally, the method for judging the quality of the casting process includes:

[0071] Select time periods of day and night shifts, different seasons of winter, summer, autumn and winter, continuous rainy days or snowy and frosty days, check the slurry quality data and casting quality data, combine the product qualification rate and cost, analyze the factors affecting product quality, and judge the quality of the casting process.

[0072] Optionally, the rationality of the monitoring riser design may be specifically determined by:

[0073] According to the images and video records, check the relationship between the riser size and casting speed, casting time, casting position, slurry solidification rate, riser solidification area-casting time, and the weight ratio of the riser after cutting, analyze the rationality of the riser size and size, and obtain the optimal riser size for different brick types.

[0074] In a second aspect, the present invention provides an online multifunctional quality monitoring system for a molten refractory material casting process, comprising:

[0075] The thermal imager, computer and remote monitoring system are connected in sequence.

[0076] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0077] The present invention uses video recording to record the temperature cloud map of the casting system. The instantaneous maximum temperature and its average value, i.e., the casting temperature, in the cloud map can be used to conveniently observe and analyze changes in the liquid temperature. The temperature cloud map can also be used to conveniently find the shape, quantity, and time point of the inclusions (low temperature zone), and it is also convenient to analyze the effects of inclusions on the quality of castings. The list of data and time such as the maximum temperature, average temperature, and point temperature recorded by the present invention can conveniently find characteristic data such as the discharge temperature, the molten material temperature, and the liquid temperature of the casting process for later analysis and processing. The use of a short-wave thermal imager further improves the accuracy and precision of temperature measurement, and the temperature measurement accuracy is ±0.01°C, making the advantages of the present invention more obvious; the present invention can also accurately record the casting time, which is convenient for accurately calculating parameters such as the casting speed and the cooling speed. The current method is to manually time with a stopwatch, which is accurate to the second and has a maximum error of ±2 seconds. Therefore, the casting time is several seconds to tens of seconds. The timing unit of the present invention is accurate to microseconds, and the timing accuracy is improved by 1000 times. When the slurry starts to be cast, the system automatically starts timing, and the maximum time difference is a temperature measurement interval such as 25 microseconds. When the slurry casting ends or the highest temperature of the system is lower than the set temperature, the timing automatically ends, and the maximum time difference is a temperature measurement interval of 25 microseconds, so the maximum timing error is ±50 microseconds. The total casting time is automatically calculated by the computer, which is convenient and fast, and is convenient for manually calculating the casting speed in combination with the casting amount; the accurate video recording of temperature and time of the present invention can facilitate later analysis and processing. Compared with the current casting process, the casting workers wear goggles to observe the casting position, material flow size, sand mold filling situation and riser overflow situation, and adjust the casting speed in time. In this way, it is necessary to observe the casting speed of the furnace nozzle outlet on the left to prevent the material liquid from pouring out of the furnace nozzle and causing an accident, and to observe the sand mold filling situation on the right to prevent the material liquid from overflowing the riser, especially within a few seconds, it is usually difficult to observe the inclusions of the material liquid in the middle position, and the white light seen by the goggles can easily cover up the inclusions of the material liquid or the uneven temperature of the material liquid, and it is even more impossible to check it later. The present invention adopts a short-wave thermal imager for video recording, and the minimum time interval of video acquisition can be set to 1 microsecond, which is very convenient for recording various situations. The later video playback can be viewed at 8 times, 4 times, 2 times, 1 times, 1 / 2 times, 1 / 4, and 1 / 8 times, which is convenient for finding more details.The temperature fluctuation display is more intuitive. For example, the temperature measurement starts when the maximum temperature is set to be slightly higher than the instantaneous maximum temperature of the system, and the temperature measurement ends when the minimum temperature is set to be slightly lower than the minimum temperature of the system. In this way, the minimum temperature measurement range can be 300-400°C, or even 100-200°C. Various temperatures are further marked with 10 or even 20 colors. Therefore, it is easy to find temperature unevenness and material liquid inclusions according to the different displayed colors. The present invention records the exact data of various temperatures and times, making it possible to increase quality monitoring parameters and monitoring means, so that waste can be discovered and processed early, and waste can be discovered only after cooling, heat preservation, or even cutting and grinding. This reduces losses, improves the significance of process quality monitoring, and adds a remote monitoring function, thereby improving the monitoring capability of enterprises in process quality monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0079] Figure 1 A flow chart of an online multifunctional quality monitoring method for a fused refractory material molten casting process provided by the present invention;

[0080] Figure 2 The image is captured by the infrared thermal imager provided by the present invention. DETAILED DESCRIPTION

[0081] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0082] The purpose of the present invention is to provide an online multifunctional quality monitoring system for the casting process of fused refractory molten metal, so as to accurately reflect the temperature and distribution of the casting system, accurately record the casting time, and realize remote monitoring.

[0083] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0084] Embodiment 1

[0085] See also Figure 1The present invention provides an online multifunctional quality monitoring method for a molten refractory material casting process, comprising:

[0086] Step 1: Determine the emissivity of the casting liquid.

[0087] According to the installation conditions of the thermal imager and the characteristic parameters such as the casting volume of the casting product, the exposure time is selected as 25 microseconds, the test distance is 4.5 meters, and the environmental condition is the normal ambient temperature (25°C). The deviation between the instantaneous maximum temperature and the actual temperature of the casting liquid under different emissivity conditions is studied. The emissivity when the instantaneous maximum temperature of the liquid at the furnace nozzle outlet reaches the actual temperature test value is determined as the emissivity of the liquid during casting. The emissivity test method for other temperatures is similar, and the emissivity under different temperature conditions is obtained. Based on this, the emissivity coefficient function of the molten casting liquid when the thermal imager is measuring the temperature is determined, λ=A+BX+CX 2 , where λ is the emissivity, A, B or C are constants, and X is the temperature to improve the temperature measurement accuracy. If the exposure time changes, the test distance changes, or the ambient temperature changes, the emissivity at different temperatures will change.

[0088] Step 2: Determine the material temperature.

[0089] Specifically include:

[0090] During the casting process, the maximum temperature of the liquid is measured every 25 microseconds, which is the instantaneous maximum temperature;

[0091] Take the highest value of all instantaneous maximum temperature values ​​recorded during the casting process as the material temperature.

[0092] Step 3: Determine the discharge temperature.

[0093] Specifically, the temperature of the highest point of the material liquid surface at the end of the furnace nozzle recorded during the casting process is used as the discharge temperature.

[0094] Step 4: Determine the casting temperature.

[0095] In the parameter setting interface of the thermal imager software, we select the highest temperature, and calculate the average value of the instantaneous highest temperature according to the statistical value of the instantaneous highest temperature in the liquid area during the casting process as the casting temperature. The specific value-taking method is to measure the highest temperature every certain period of time, such as 25 microseconds, during the casting process. The average value of dozens to thousands of instantaneous highest temperatures obtained during the entire casting process is the characteristic casting temperature of the casting process, which is used to compare and analyze the rationality and stability of the process.

[0096] Step 5: Monitor the quality of the casting liquid.

[0097] The quality of the liquid feed includes the discharge temperature, alarm temperature, liquid feed temperature and its uniformity, and whether there are inclusions in the liquid feed. In the parameter setting interface of the thermal imager software, we set the maximum and minimum values ​​of the alarm temperature. If the highest temperature in the monitoring area of ​​the thermal imager reaches or exceeds the highest alarm temperature, or the lowest temperature in the monitoring area reaches or falls below the lowest alarm temperature, the system will sound an alarm, and the operator needs to check and deal with it accordingly. For example, a low temperature alarm may mean that there are inclusions, or the liquid feed temperature may be too low after refining, so it needs to be handled as appropriate.

[0098] Under the condition of accurate temperature measurement, monitoring the discharge temperature means selecting a point on the liquid surface at the end of the furnace nozzle and recording the temperature at the point as the discharge temperature. It is a dynamic data. If the computer monitors that the data is too low and reaches the lowest value of the alarm temperature, it is necessary to stop casting and continue refining. If the discharge temperature is too high, it is necessary to reduce the casting speed so that the temperature of the liquid in the sand mold reaches the normal range. If the instantaneous maximum temperature of the liquid is monitored to be lower than the normal specified numerical range, the casting should be stopped and the current and voltage should be increased during the next batch of material melting or refining to ensure that the instantaneous maximum temperature is within the normal range. If the instantaneous maximum temperature of the liquid is monitored to be higher than the normal specified numerical range, the casting speed should be reduced so that the temperature of the liquid in the sand mold reaches the normal range and the liquid is heated to a high temperature during the next batch of material melting or refining. When the current and voltage are reduced, the instantaneous maximum temperature is within the normal range. If the instantaneous maximum temperature of the liquid is monitored to fluctuate greatly, or the temperature difference between different parts of the liquid is large, the casting should be stopped. If the liquid is monitored to have inclusions, the nozzle material is falling off, or the sputtering cooling material block is falling off into the sand mold, the box number should be marked for scrapping, and the type of inclusions in the liquid should be preliminarily determined through the analysis of the thermal imager image to facilitate targeted improvement of the process. If there are relatively obvious large fixed-shaped low-temperature areas in the liquid, it may be the nozzle material falling off. If there are scattered low-temperature small dots flowing with the liquid, it is possible that the unmelted powder around the furnace has fallen. The large low-temperature area next to the inner wall of the sand mold rolls and sinks in the liquid, it is possible that the liquid splashed on the side wall is cooled and then swept away by the subsequent liquid. If the thermal imager monitors large flowing areas or continuous irregular low-temperature areas, it is mainly caused by uneven liquid in the furnace; the temperature of the liquid in the furnace is too low and the viscosity is too high, and the boundary of the liquid flow is not smooth, which may cause dripping under the liquid or cause cooling cracks in the casting. Once these unexpected phenomena occur, the box number should be immediately marked as scrap and no further process should be carried out.

[0099] Step 6: Monitor the quality of the casting operation.

[0100] The operation quality mainly includes the casting time obtained after the processing of the data recorded by the thermal imager (the time difference between the start and end of casting, which is automatically recorded by the system), casting speed (casting volume divided by casting time, obtained by manual data processing), casting position (casting position recorded by the thermal imager image), overflow after full pouring (liquid overflowing from the riser recorded in the thermal imager image. Since it is difficult for workers to control the sand mold to be filled every time, the situation of waste of liquid caused by overflow of the sand mold often occurs, which increases the cost), supplementary pouring and exhaust (manual operation recorded by the thermal imager) and other operation parameters. According to the operating procedures, if the casting speed is too fast or too slow, or the casting time is too long or too short, the box number should be marked for scrapping; if there is overflow after full pouring, the material loss should be calculated through the material blocks detected after cooling, and rewards and penalties should be given; if the monitoring records that the casting position deviates from the normal area, the box number should be marked to check whether the casting has defects; supplementary pouring or exhaust operations should be carried out in accordance with the regulations, and records of missing or excessive operations are used as the basis for rewards and penalties.

[0101] Step 7: Calculate the condensation rate of the slurry.

[0102] The coagulation rate of the slurry changes with the climate changes throughout the year and with the casting temperature. Different coagulation rate conditions require different slurry composition, casting speed, exhaust times and intervals. Therefore, the slurry coagulation rate is an important parameter for casting quality. The specific calculation method is to start timing and recording the liquid surface temperature in the sand box at the end of casting, and end recording when the liquid surface solidifies. The duration of the period divided by the temperature difference is the slurry coagulation rate. During the stable production process, the slurry coagulation rate should be measured during the day, at night, and when the climate changes (such as rainy days, sudden temperature drops, strong winds, snowy days, etc.) to ensure the optimal casting process quality and stable product quality.

[0103] Step 8: Judge the quality of the casting process.

[0104] By comparing parameters such as casting temperature, casting speed, casting time, liquid overflow rate, etc. for different work groups and time periods (such as day shift, night shift, spring, summer, autumn and winter, etc.), combined with the final defect statistics of the product, we can obtain a basis for judging the quality of the casting process under the conditions of each work group and time period, and also provide strong data and theoretical support for obtaining the best casting process parameters for the product and improving the pass rate.

[0105] Step 9: Monitor the rationality of the riser design.

[0106] The temperature of the slurry is different, the streamline of casting is different, the initial slurry entry point and the entry point at maximum flow are different, and the distance between the two is the minimum size of the upper surface of the riser. Otherwise, the larger the riser, the faster the cooling and the weaker the shrinkage compensation function. The brick sizes are different, the shrinkage amounts are different, and the required riser sizes are also different. Therefore, on the basis of the minimum upper surface size, the minimum depth of the riser is determined according to the shrinkage compensation amount. The greater the cooling rate of the riser, the larger the size of the lower surface of the riser should be, and the smaller the cooling rate of the riser, the smaller the size of the lower surface of the riser is required to achieve the maximum shrinkage compensation function as much as possible. In short, the design of the riser size must meet the needs of the casting process and the shrinkage compensation function. On this basis, using the smallest possible riser can greatly reduce costs.

[0107] Embodiment 2

[0108] In order to execute the method corresponding to the above-mentioned embodiment 1, a multifunctional online monitoring system for molten refractory material casting is provided below, comprising:

[0109] Thermal imagers, computers and remote monitoring systems connected in sequence;

[0110] The thermal imager includes: an infrared lens, an infrared detector, an image acquisition module, an image processing module and a data transmission module;

[0111] Among them, the infrared lens is used to capture images;

[0112] Infrared detectors are used to detect high temperature areas and measure high temperatures;

[0113] The image acquisition module is used to record and store image information;

[0114] The image processing module is used to analyze image data;

[0115] The data transmission module is used to operate the thermal imager via a computer and perform remote monitoring.

[0116] See also Figure 2 In the figure, different colors represent different temperatures. In the system, put the mouse at any point to read the temperature of that point. The flow stream is obviously bifurcated, and the shape of the upper area is similar to the shape of the furnace nozzle. It can be determined that the furnace nozzle material falls off and enters the sand mold with the liquid flow.

[0117] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0118] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. An online multifunctional quality monitoring method for the molten refractory casting process, characterized in that: include: Determining the emissivity of the casting liquid specifically includes: constructing an emissivity-temperature function of the liquid according to the recorded temperature data at different emissivities; obtaining a function correction parameter according to the highest temperature deviation and the lowest temperature deviation using the function relationship measured at least five times; correcting the emissivity-temperature function according to the function correction parameter to obtain a corrected emissivity-temperature function; based on the corrected emissivity-temperature function, obtaining the emissivity at the temperature according to the measured temperature; Determine the temperature of the material; Determine the discharge temperature; Determine the casting temperature; Monitor the quality of the casting liquid, specifically including: using the recorded images and videos to monitor the liquid's slurry temperature, discharge temperature, alarm temperature, casting temperature, liquid temperature at a certain point in the liquid flow, the overall temperature uniformity of the liquid, and whether there are foreign objects in the liquid; Monitoring the operational quality of casting, specifically including: monitoring the casting time, casting speed, casting position, amount of overflow after full pouring, number of supplementary pouring and number of exhausting obtained after processing the data recorded by the thermal imager; the casting time is the casting time interval recorded by the video during the casting process; the casting speed is obtained by dividing the casting amount by the casting time; the casting position is the casting position determined according to the process rules; the amount of overflow after full pouring is when there is overflow after full pouring, the overflow material is detected by cooling and weighing the block of material to calculate the material loss; when the casting speed is not within the preset speed range or the casting time is not within the preset time range, mark the product for scrapping and wait for the subsequent process to verify whether it is qualified; if the amount of overflow after full pouring exceeds the specified material loss, it is necessary to urge to improve the final casting speed; if the monitoring record shows that the casting position deviates from the normal area, the product should be marked for subsequent process inspection to see if the casting is defective; according to the monitoring records, determine whether the supplementary pouring or exhaust meets the specifications and whether there are records of missing or excessive operations; Calculate the condensation rate of the liquid; Judge the quality of the casting process; Monitor the rationality of riser design.

2. The online multifunctional quality monitoring method for the molten refractory material casting process according to claim 1 is characterized in that: Determining the material temperature, the discharge temperature and the casting temperature specifically comprises the following steps: During the casting process, the maximum temperature of the liquid is measured every 25 microseconds, which is the instantaneous maximum temperature; Take the highest value of all instantaneous maximum temperature values ​​recorded during the casting process as the material temperature; The temperature of the highest point of the liquid surface at the end of the furnace nozzle recorded during the casting process is used as the discharge temperature; The instantaneous maximum temperature recorded during the casting process is averaged as the casting temperature; The material temperature is a temperature data, and the instantaneous maximum temperature, discharge temperature and casting temperature are all dynamic data.

3. The online multifunctional quality monitoring method for the molten refractory material casting process according to claim 1 is characterized in that: Using the recorded images and videos, monitor the slurry temperature, discharge temperature, alarm temperature, casting temperature, slurry temperature at a certain point in the liquid flow, the overall temperature uniformity of the slurry, and whether there are foreign objects in the slurry; the specific quality monitoring method includes the following steps: Set the maximum alarm temperature; When the temperature in the monitored area reaches or exceeds the maximum alarm temperature, an alarm is issued; When the liquid temperature in the monitoring area has a local regular low temperature area and flows with the liquid, it is determined that there are impurities in the liquid; By analyzing the thermal imager images, the type of inclusions in the liquid can be determined; And according to the number and type of inclusions, determine whether the product is qualified or whether to enter the next process; When monitoring detects that nozzle material or sputtering cooling material blocks have fallen off in the liquid and entered the sand mold, mark whether the product should be scrapped based on the size and quantity of the nozzle material blocks, or the size, quantity, falling position and time of the sputtering cooling material blocks, and adjust the irregular operation through analysis and judgment of the thermal imager image to ensure the normal operation of the next furnace; If the discharge temperature, chemical temperature or casting temperature is monitored to be too high and exceeds the upper limit of the discharge temperature set by the system, the casting speed needs to be reduced to make the temperature of the material liquid in the sand mold reach the normal range or the casting needs to be suspended; If the discharge temperature, melting temperature or casting temperature is monitored to be low and exceeds the lower limit of the alarm temperature set by the system, it is necessary to stop casting and continue refining, and increase the current and voltage in the next melting or refining to ensure that the discharge temperature is within the normal range; If the maximum instantaneous temperature of the liquid is higher than the maximum alarm temperature, the casting speed should be reduced so that the temperature of the liquid in the sand mold reaches the normal range, and the current and voltage should be reduced during the next batch of melting or refining to ensure that the maximum instantaneous temperature is within the normal range; If the instantaneous maximum temperature of the liquid is monitored to be lower than the minimum alarm temperature, the casting should be stopped and the current and voltage should be increased during the next batch of melting or refining to ensure that the instantaneous maximum temperature is within the normal range; If it is monitored that the instantaneous maximum temperature of the slurry fluctuates greatly, or the temperature of different parts of the slurry differs greatly, casting should be stopped, and refining should be continued until the slurry temperature is uniform before casting again.

4. The online multifunctional quality monitoring method for the fused refractory material molten casting process according to claim 1 is characterized in that: By analyzing the thermal imager image, the type of inclusions in the liquid is determined, which specifically includes the following steps: If there is an obvious large fixed-shape low-temperature area in the liquid material, it is judged that the furnace nozzle material has fallen off; If there are scattered low-temperature small dots in the liquid that flow with the liquid, it is judged that the unmelted powder around the furnace has fallen; If a large low-temperature area next to the inner wall of the sand mold rolls and sinks in the liquid, it is judged as a sputtering cooling block, that is, the liquid splashed onto the side wall is cooled and then swept away by the subsequent liquid; If large flowing pieces or continuous irregular low-temperature areas are detected, it is judged that the liquid in the furnace is not uniform and the material operation needs to be improved; If the temperature difference between the feed and liquid is large, or the temperature drops too quickly during the discharge process, resulting in excessive viscosity of the feed and liquid, uneven boundary of the feed and liquid streams, or dripping under the feed and liquid, the product is judged to be a scrapped product and needs to be verified in the later process to see if it is qualified. The next batch needs to extend the material dissolving time or take measures to reduce the temperature drop.

5. The online multifunctional quality monitoring method for the fused refractory material molten casting process according to claim 1 is characterized in that: The specific calculation method of the slurry coagulation rate includes: Start timing and recording the temperature of the liquid surface in the sand box when casting is finished, and stop recording when the liquid surface solidifies; The duration of the recording period divided by the temperature difference is the condensation rate of the slurry.

6. The online multifunctional quality monitoring method for the fused refractory material molten casting process according to claim 1 is characterized in that: The specific method for judging the quality of the casting process includes: Select time periods of day and night shifts, different seasons of winter, summer, autumn and winter, continuous rainy days or snowy and frosty days, check the slurry quality data and casting quality data, combine the product qualification rate and cost, analyze the factors affecting product quality, and judge the quality of the casting process.

7. The online multifunctional quality monitoring method for the fused refractory material molten casting process according to claim 1 is characterized in that: The rationality of the monitoring riser design is specifically determined by: According to the images and video records, check the relationship between the riser size and casting speed, casting time, casting position, slurry solidification rate, riser solidification area-casting time, and the weight ratio of the riser after cutting, analyze the rationality of the riser size and size, and obtain the optimal riser size for different brick types.

8. An online multifunctional quality monitoring system for the molten refractory casting process, characterized in that: include: Thermal imagers, computers and remote monitoring systems connected in sequence; The computer is used to execute the online multifunctional quality monitoring method for the molten refractory material casting process according to any one of claims 1 to 7; The thermal imager comprises: an infrared lens, an infrared detector, an image acquisition module, an image processing module and a data transmission module; wherein the infrared lens is used to capture images; Infrared detectors are used to detect high temperature areas and measure high temperatures; The image acquisition module is used to record and store image information; The image processing module is used to analyze image data; The data transmission module is used to operate the thermal imager via a computer and perform remote monitoring.

Images