Artificial board production method and system based on digital informatization platform

Abstract

The invention provides an artificial board production method and system based on a digital informatization platform, and relates to the technical field of production technology.The artificial board production system comprises an artificial board base material base arranged in a forestry resource-rich area and used for processing forest resources and plant fiber raw materials into an artificial board base material of a shaving board or a fiberboard; the printing, dipping and pressing industrial area and the artificial board base material base are arranged in a centralized mode, and the printing unit comprises a plurality of sets of photogravure printing machines and is used for printing body paper to form artificial board facing decorative paper; the glue dipping unit is used for dipping the printed artificial board decorative paper into a hot-melt melamine glue solution through a glue dipping tank; the pressing and pasting unit is used for performing high-temperature oil pressing on the artificial board base material and the impregnated artificial board facing decorative paper to form a finished board; an intelligent logistics system for centralized production process management and control is used for carrying out intelligent automatic linkage on equipment of a printing unit, an impregnation unit and a pressing and pasting unit, the production cost of an integrated industrial area is greatly reduced, and high-quality management and control can be carried out.

Description

Technical Field

[0001] The present invention relates to production technology, and in particular to a method and system for producing artificial boards based on a digital information platform. Background Art

[0002] As an important product in the wood processing industry, wood-based panels are widely used in architectural decoration, furniture manufacturing and other fields. With the advent of the Industrial 4.0 era, traditional wood-based panel production methods face many challenges, such as low production efficiency, difficult quality control, and serious waste of resources.

[0003] The so-called artificial board is a piece of base material of two types, particleboard and fiberboard, made from fast-growing trees, plant fiber waste and limbs of forestry resources. The mixed colloid is heated, stirred and input into a high-pressure continuous press to be pressed into block-shaped artificial base board cut into standard sizes.

[0004] There are five major production process blocks in the wood-based panel industry chain: namely, base material board factory, decorative paper base paper factory, decorative paper printing factory, printing and dipping factory, and cardboard pressing and finishing board factory. Currently, most of them are single industries.

[0005] As for the base material factory, this production resource depends on the regional requirements of the forestry resource area and is packaged in cubic units. Its market basically has long-distance transportation logistics across provinces and regions. In this case, the logistics cost is extremely high.

[0006] Other factories make independent settings based on their own production and operation conditions. This approach will greatly increase the intermediate transportation costs. At the same time, the phenomenon of information islands is serious, and the data of each production link cannot be shared and linked in real time, resulting in delayed production decisions.

[0007] Quality control is difficult, processes are fragmented, and there is a lack of real-time monitoring of the entire process.

[0008] In the current era of technological generation gap, the integration of the entire production process is imminent. Summary of the invention

[0009] The embodiments of the present invention provide a method and system for producing artificial boards based on a digital information platform, which can solve the problems in the prior art.

[0010] According to a first aspect of the embodiments of the present invention,

[0011] Provide wood-based panel production system based on digital information platform, including:

[0012] The artificial board base is located in the forestry resource-rich area, and is used to process forest resources and plant fiber raw materials into particleboard or fiberboard artificial board base;

[0013] It also includes a printing, dipping and pressing industrial zone centrally arranged with the artificial board substrate base, wherein the printing unit includes a plurality of groups of gravure printing machines for printing base paper to form artificial board facing decorative paper;

[0014] The dipping unit is used to dip the printed wood-based panel decorative paper into hot-melt melamine glue through the dipping tank;

[0015] The pressing unit is used to press the artificial board substrate and the artificial board veneer decorative paper after impregnation with glue at high temperature to form a finished board;

[0016] The intelligent logistics system with centralized production process control is used to realize intelligent and automated linkage of the equipment of the printing unit, the dipping unit and the pressing unit.

[0017] In an optional embodiment,

[0018] The gravure printing unit adopts synchronous transmission technology to ensure high-precision alignment of various printed patterns; the printing process uses environmentally friendly water-based ink, and after infrared drying, a flexographic printing process is used to print a layer of wear-resistant protective coating on the surface, including:

[0019] During the gravure printing process, environmentally friendly water-based ink is printed on the base paper. The water-based ink uses water as a dispersion medium and is prepared by adding resin, colorant and additives to water. The base paper printed with the water-based ink then passes through an infrared drying unit, where it is directly heated by infrared radiation and quickly dried at 50-60°C, reducing the residual moisture in the ink layer to less than 3%.

[0020] The dried base paper is then printed with a layer of wear-resistant protective coating on the surface through a flexographic printing process. Flexographic printing uses a flexible resin plate, and the coating ink is composed of UV-curable resin, nano-aluminum oxide particles and additives. During the flexographic printing process, the printing pressure and dot area coverage are precisely controlled, and the coating is cured with a GaN-based UV LED lamp to form a surface coating with excellent hardness and flexibility. The coating thickness is 20-30μm, and the surface hardness is not less than 4H.

[0021] In an optional embodiment,

[0022] The method further comprises:

[0023] Passing the decorative base paper through a plurality of sequentially arranged gravure printing units, wherein in each gravure printing unit, the base paper contacts a gravure roller provided with a printing pattern of different colors and transfers the pattern;

[0024] Multiple groups of gravure printing units adopt a synchronous transmission control system, which includes a rotary encoder, a servo motor and its driver, and a central synchronous controller arranged at the end of each gravure roller shaft;

[0025] The synchronous controller sends control instructions to each servo driver in real time through industrial Ethernet according to the target speed curve of each gravure roller that needs to rotate synchronously, combined with the feedback signal of the rotary encoder, to accurately control the rotation speed and phase of each gravure roller, thereby achieving high-precision alignment of printed patterns of different colors.

[0026] In an optional embodiment,

[0027] The decorative paper dipping unit immerses the printed decorative paper into the hot melt melamine glue through the dipping tank. After saturated absorption, the glue is then adjusted by the squeeze roller to adjust the uniformity of the glue distribution. Then, the glue is cured into a film by a combined drying process of hot air and infrared rays. The process includes:

[0028] The melamine resin powder is mixed with water and a catalyst, and the mixture is stirred and kept warm at 85°C to dissolve the resin and perform preliminary polycondensation, and then a formaldehyde solution is added to continue the reaction to obtain a formaldehyde melamine resin; the mixture is heated and kept warm again to promote further polycondensation of the resin to obtain a glue solution with a viscosity of 10000 mPa·s, and a wetting agent and a defoaming agent are added after cooling to obtain a hot melt melamine glue solution which is semi-solid at room temperature;

[0029] The hot melt melamine glue solution is heated to a molten state and poured into a dipping tank, and the temperature of the glue solution is controlled to be constant at 70-80° C. The decorative paper after gravure printing and flexographic printing is continuously passed through the dipping tank for dipping and absorption, and then a pair of squeezing rollers with mesh surfaces are used to hydraulically squeeze the paper, and the gap between the squeezing rollers and the line pressure are adjusted to control the liquid holding rate of the paper within the range of 100%-180%;

[0030] The impregnated paper is dried by combining hot air drying and infrared drying. The hot air drying section is equipped with multiple independently temperature-controlled drying chambers, and the hot air temperature increases step by step from 130°C to 180°C. The infrared drying section uses quartz tube short-wave infrared radiators to radiate heating to the paper, and the radiation power density is not less than 50kW / m2, ultimately reducing the moisture content of the paper to below 3%.

[0031] In an optional embodiment,

[0032] The decorative paper after impregnation is then cut into decorative units matching the size of the substrate by a flexible cutting unit, including:

[0033] The decorative paper that has been impregnated and dried is transported to a flexible cutting machine equipped with a laser ranging sensor. The control system measures the paper position in real time and calculates the target linear speed of the circular knife. The servo motor drives the rotation of the circular knife in synchronization with the paper transportation. The circular knife adopts a thin blade design with a thickness of no more than 0.2mm, and an ultrasonic vibrator is set underneath it with a frequency of 2040kHz and an amplitude of 515μm. The circular knife and the paper maintain dynamic speed synchronization, and the linear speed range is 20 to 120m / min.

[0034] In an optional embodiment,

[0035] During the pressing process, the online optical defect detection system performs AI intelligent detection on the surface quality of the panels, and feeds back the defect information to the press control system to adjust the process parameters in real time; the centrally controlled intelligent logistics system, composed of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches the materials of substrates, decorative paper, and finished panels between each processing unit; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks, optimize the balance of production lines, and improve equipment utilization, including:

[0036] A high-resolution linear array CCD camera is installed at the exit section perpendicular to the moving direction of the continuous pressing production line of veneer wood-based panels to collect images of the panel surface. The image data is transmitted to the industrial computer in real time by the image acquisition card. The industrial computer runs a defect detection algorithm software based on a convolutional neural network to preprocess, segment, extract features, and classify and identify the image to determine whether there are defects such as indentations, bubbles, scratches, and stains on the panel surface. The detection results include defect type, size, and coordinate position information.

[0037] The defect detection results are uploaded to the MES system database and input into the press adaptive expert decision module as feedback signals. This module builds a mathematical model of process parameters, defect types and occurrence rates based on machine learning algorithms, evaluates the risk of various defects in combination with real-time detection data streams, and automatically infers the dynamic adjustment strategy of process parameters such as oil plate temperature and roller pressure. It generates executable control instructions and sends them to the press PLC to achieve closed-loop optimization control of defect detection feedback and press process parameters.

[0038] In an optional embodiment,

[0039] The centrally controlled intelligent logistics system consists of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, which automatically transport and cache the materials of substrates and finished boards between various processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks; the AGV cart uses the laser SLAM navigation algorithm to autonomously plan the path and deliver the decorative paper rolls and substrates to the designated production line;

[0040] A six-axis manipulator is used to pick up the finished veneer panels and stack them on the RGV trolley pallet, and the stacking adopts an accordion-style staggered method; the RGV trolley automatically transports the finished products along the track to the front of the vertical warehouse, and then the high-position fork robot transports them into the warehouse; the vertical warehouse uses a combination of fork-type shuttle vehicles and multi-layer elevators, and the inventory data is shared with the production plan of the MES system;

[0041] The warehouse management software automatically generates instructions for picking and dispatching decorative panels according to production tasks and delivery dates, optimizing the allocation of storage and retrieval locations. The operating status data of logistics equipment is transmitted back to the MES system in real time, and scheduling is optimized through status monitoring and efficiency analysis, thereby improving equipment utilization and shortening material turnover time.

[0042] According to a second aspect of the embodiments of the present invention,

[0043] Provide a method for producing wood-based panels based on a digital information platform, including:

[0044] The artificial board substrate preparation unit arranged in the forestry resource-rich area is used to process the plant fiber raw materials of wood into the substrate of particleboard or fiberboard;

[0045] The printed decorative paper is immersed in hot melt melamine glue through a dipping tank. After saturated absorption, the glue is evenly distributed through a squeeze roller, and then the glue is cured into a film by a combined drying process of hot air and infrared rays. The dipped decorative paper is then cut into facing units that match the size of the substrate by a flexible cutting unit.

[0046] The substrate is automatically positioned and accurately transported to the continuous press, where the veneer and substrate are firmly bonded through the oil pressure process;

[0047] The centrally controlled intelligent logistics system, which is composed of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches substrates and finished board materials between processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks.

[0048] In order to improve the surface wear resistance of decorative paper and extend its service life, the present invention adopts a flexographic printing process after gravure printing to print a layer of high-strength wear-resistant coating on the surface of decorative paper. The coating is composed of ultraviolet curing resin, nano-alumina particles, additives and other components, and the coating formed after curing has excellent hardness and flexibility.

[0049] The intelligent logistics system is interconnected with the MES system, and inventory data and production plans are shared. According to production tasks and delivery dates, the warehouse management software automatically generates instructions for picking and dispatching panels, optimizes the allocation of cargo spaces, and shortens material turnover time. At the same time, the operating status data of logistics equipment is also transmitted back in real time, which facilitates statistical analysis of equipment utilization and efficiency, taps equipment potential, and optimizes production line balance. Through the flexible scheduling of the intelligent logistics system, material distribution, cache turnover, and finished product warehousing and warehousing in the production of decorative panels have achieved a high degree of automation and information transparency, significantly improving production efficiency and equipment utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1It is a schematic diagram of the process of the method for producing artificial boards based on a digital information platform according to an embodiment of the present invention;

[0051] Figure 2 It is a structural schematic diagram of a wood-based panel production system based on a digital information platform according to an embodiment of the present invention. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings 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.

[0053] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0054] Figure 1 FIG. 1 is a flow chart of a method for producing artificial boards based on a digital information platform according to an embodiment of the present invention. Figure 1 As shown, the method includes:

[0055] S101. The artificial board substrate preparation unit arranged in the forestry resource-rich area is used to process the plant fiber raw materials of wood into the substrate of particle board or fiberboard; the printed decorative paper is immersed in the hot melt melamine glue through the glue dipping tank, and after saturated absorption, the uniformity of the glue distribution is adjusted by the squeeze roller, and then the glue is cured into a film by the hot air and infrared combined drying process; the decorative paper after dipping is cut into a facing unit matching the size of the substrate by the flexible cutting unit;

[0056] S102. The substrate is automatically positioned and accurately transported to the continuous press, and the veneer and the substrate are firmly bonded through the oil pressure process in the press;

[0057] S103. The centrally controlled intelligent logistics system consists of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, which automatically transport and cache substrates and finished board materials between processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks.

[0058] In an optional embodiment,

[0059] The gravure printing unit adopts synchronous transmission technology to ensure high-precision alignment of various printed patterns; the printing process uses environmentally friendly water-based ink, and after infrared drying, a flexographic printing process is used to print a layer of wear-resistant protective coating on the surface, including:

[0060] The decorative base paper is sequentially passed through a plurality of groups of sequentially arranged gravure printing units, in each gravure printing unit, the base paper contacts a gravure roller provided with a printing pattern of different colors and transfers the pattern; the plurality of groups of gravure printing units adopt a synchronous transmission control system, the control system comprises a rotary encoder, a servo motor and a driver thereof, and a central synchronous controller arranged at the shaft end of each gravure roller; the synchronous controller sends control instructions to each servo driver in real time through industrial Ethernet according to a target speed curve of each gravure roller requiring synchronous rotation, combined with a feedback signal of the rotary encoder, to accurately control the rotation speed and phase of each gravure roller, and realize high-precision alignment of printing patterns of different colors;

[0061] During the gravure printing process, environmentally friendly water-based ink is printed on the base paper. The water-based ink uses water as a dispersion medium and is prepared by adding tree resin, colorants and additives to water. The base paper printed with water-based ink then passes through an infrared drying unit, where it is directly heated by infrared radiation and quickly dried at 50-60°C, reducing the residual moisture in the ink layer to less than 3%.

[0062] The dried base paper is then printed with a layer of wear-resistant protective coating on the surface through a flexographic printing process. Flexographic printing uses a flexible resin plate, and the coating ink is composed of UV-curable resin, nano-aluminum oxide particles and additives. During the flexographic printing process, the printing pressure and dot area coverage are precisely controlled, and the coating is cured with a GaN-based UV LED lamp to form a surface coating with excellent hardness and flexibility. The coating thickness is 20-30μm, and the surface hardness is not less than 4H.

[0063] In an optional embodiment,

[0064] The method further comprises:

[0065] Passing the decorative base paper through a plurality of sequentially arranged gravure printing units, wherein in each gravure printing unit, the base paper contacts a gravure roller provided with a printing pattern of different colors and transfers the pattern;

[0066] Multiple groups of gravure printing units adopt a synchronous transmission control system, which includes a rotary encoder, a servo motor and its driver, and a central synchronous controller arranged at the end of each gravure roller shaft;

[0067] The synchronous controller sends control instructions to each servo driver in real time through industrial Ethernet according to the target speed curve of each gravure roller that needs to rotate synchronously, combined with the feedback signal of the rotary encoder, to accurately control the rotation speed and phase of each gravure roller, thereby achieving high-precision alignment of printed patterns of different colors.

[0068] For example, in a multi-color gravure printing unit, in order to achieve accurate overprinting of different color printing patterns, it is necessary to ensure that the printing speed of each printing unit is consistent and the phase is synchronized. The present invention adopts electronic gear synchronous transmission technology to connect the drive motor of each printing unit to the synchronous controller through industrial Ethernet. The synchronous controller calculates the target speed and position of each motor in real time according to the fixed phase relationship between the printing units, and sends control instructions to the servo driver of each motor. The servo driver achieves precise control of the motor speed and phase through high-precision position feedback and speed feedback, so that the plate rollers of each printing unit rotate synchronously to ensure overprinting accuracy.

[0069] In specific implementation, the synchronous transmission system of the printing unit can adopt the following technical solutions:

[0070] 1) Use servo motors with high-resolution encoders as the drive motors of each printing unit. The resolution of the encoder is not less than 1,000,000 pulses / rev, and the speed response bandwidth of the motor is greater than 200Hz to ensure high dynamic performance;

[0071] 2) The printing unit adopts a closed-loop control mode, and a rotary encoder is installed at the end of the plate roller shaft to detect the angle position of the plate roller in real time, and the position signal is input into the synchronous controller as feedback;

[0072] 3) For each printing unit, the synchronous controller calculates the target angle position curve of each plate roller according to the plate travel length of the current printing pattern and the circumference of the plate roller, and then discretizes the curve into a data table of angle-time points and sends it to each servo driver;

[0073] 4) The servo driver adjusts the torque output of the motor in real time according to the target angle-time point data sent by the synchronous controller, controls the plate roller to follow the target curve with high precision, and ensures that the registration accuracy of the pattern in each printing unit is better than 0.02mm;

[0074] 5) In order to improve the control accuracy of the system, intelligent control algorithms such as feedforward control and reference trajectory tracking can be introduced in the closed-loop control, and adaptive parameter adjustment methods can be used to compensate for the influence of nonlinear factors such as clearance and friction in the mechanical transmission system.

[0075] By adopting the above-mentioned synchronous transmission control scheme, the multi-color gravure printing unit can achieve a registration accuracy of up to 1200DPI, meeting the printing requirements of high-definition decorative paper.

[0076] In order to reduce the emission of volatile organic compounds, the present invention adopts water-based ink to replace traditional solvent-based ink in decorative paper printing. Water-based ink uses water as a dispersion medium and is prepared by adding resin, colorant, additives and other components to water. Compared with solvent-based ink, the VOC content of water-based ink is reduced by more than 90%, and it does not contain toxic substances such as benzene and toluene, which meets environmental protection requirements.

[0077] However, water-based ink also has problems such as slow drying speed and high requirements on paper absorbency. To solve these problems, the present invention adopts infrared drying technology after printing. Compared with the traditional hot air drying method, infrared drying has the following advantages:

[0078] 1) High drying efficiency: The infrared radiation wavelength is concentrated in the range of 0.76-1000μm, which can be selectively absorbed by water and printing substrates, directly converting radiation energy into heat energy, with a thermal efficiency close to 100%, and the drying speed is 3-5 times that of hot air drying;

[0079] 2) Fast heating speed: Since infrared radiation directly acts on the dried material, the surface of the material can be heated to 50-70°C within a few seconds, and the paper deformation is small during the drying process;

[0080] 3) Heat concentration: The effective working distance of infrared drying is in the order of tens of millimeters, and the heat can be precisely controlled in the printing area to reduce the thermal impact on the paper substrate.

[0081] In specific implementation, the rear end of the printing unit is equipped with 1 to 2 sets of infrared drying units, which use quartz tube short-wave infrared radiators to dry the printed decorative paper at a distance of 100 to 150 mm, and the power density of the unit is not less than 30kW / m2. During the drying process, the surface temperature of the paper is monitored in real time by an infrared thermometer to ensure that the temperature is constant within the range of 50 to 60°C. After infrared treatment, the residual moisture content of the printed ink layer can be controlled within 3%, meeting the subsequent surface coating requirements.

[0082] In order to improve the surface wear resistance of decorative paper and extend its service life, the present invention adopts a flexographic printing process after gravure printing to print a layer of high-strength wear-resistant coating on the surface of decorative paper. The coating is composed of ultraviolet curing resin, nano-alumina particles, additives and other components, and the coating formed after curing has excellent hardness and flexibility.

[0083] Flexographic printing uses a flexible resin plate with a raised pattern. When printing, the dots in the raised part directly transfer the ink to the surface of the substrate. Compared with gravure printing, flexographic printing has the characteristics of short plate production cycle, wide adaptability, and high dot fineness.

[0084] In the flexographic printing process of wear-resistant coating, the process parameters are controlled as follows:

[0085] 1) The line count of the flexographic printing plate should be 800-1000 LPI, and the dot area coverage should be 40%-50% to ensure the uniformity of the coating;

[0086] 2) The solid content of the coating is controlled at more than 75%, and the viscosity is 100-200mPa·s to ensure the transferability and coverage during flexographic printing;

[0087] 3) The printing pressure is controlled within 0.05-0.10 MPa, the imprint width is less than 0.2 mm, and the dot extrusion deformation rate is controlled within 10%;

[0088] 4) Use GaN-based UV LED curing device with a wavelength of 395nm, a power density of 1200mW / cm2, and a curing time of 1.5 to 2.5s;

[0089] 5) After curing, the coating has a film thickness of 20 to 30 μm, a surface hardness of not less than 4H, and a wear resistance of more than 8,000 revolutions (CS-10, 500g).

[0090] By precisely printing a wear-resistant coating on the surface of decorative paper, the physical properties of the decorative panel are improved, while the fineness of the decorative pattern is retained to the maximum extent, achieving an optimal balance between the product's visual texture and service life.

[0091] In an optional embodiment,

[0092] The decorative paper dipping unit immerses the printed decorative paper into hot melt melamine glue through the dipping tank, and after saturated absorption, the uniformity of the glue distribution is adjusted by the squeeze roller, and then the glue is cured into a film by a combined drying process of hot air and infrared rays; the decorative paper after dipping is cut into a size matching the substrate by the flexible cutting unit. The facing unit includes:

[0093] The melamine resin powder is mixed with water and a catalyst, and the mixture is stirred and kept warm at 85°C to dissolve the resin and initially polycondense it, and then a formaldehyde solution is added to continue the reaction to obtain a formaldehyde melamine resin; the mixture is heated and kept warm again to promote further polycondensation of the resin to obtain a glue solution with a viscosity of 10000 mPa·s, and a wetting agent and a defoaming agent are added after cooling to obtain a hot melt melamine glue solution which is semi-solid at room temperature;

[0094] The hot melt melamine glue solution is heated to a molten state and poured into a dipping tank, and the temperature of the glue solution is controlled to be constant at 70-80° C. The decorative paper after gravure printing and flexographic printing is continuously passed through the dipping tank for dipping and absorption, and then a pair of squeezing rollers with mesh surfaces are used to hydraulically squeeze the paper, and the gap between the squeezing rollers and the line pressure are adjusted to control the liquid holding rate of the paper within the range of 100%-180%;

[0095] The impregnated paper is dried by combining hot air drying and infrared drying. The hot air drying section is equipped with multiple independently temperature-controlled drying chambers, and the hot air temperature increases step by step from 130°C to 180°C. The infrared drying section uses quartz tube short-wave infrared radiators to radiate heating to the paper, and the radiation power density is not less than 50kW / m2, ultimately reducing the moisture content of the paper to below 3%.

[0096] In an optional embodiment, the decorative paper after being dipped in glue is cut into facing units matching the size of the substrate by a flexible cutting unit, comprising:

[0097] The decorative paper that has been impregnated and dried is transported to a flexible cutting machine equipped with a laser ranging sensor. The control system measures the paper position in real time and calculates the target linear speed of the circular knife. The servo motor drives the rotation of the circular knife in synchronization with the paper transportation. The circular knife adopts a thin blade design with a thickness of no more than 0.2mm, and an ultrasonic vibrator is set underneath it with a frequency of 2040kHz and an amplitude of 515μm. The circular knife and the paper maintain dynamic speed synchronization, and the linear speed range is 20 to 120m / min.

[0098] For example, in the process of dipping decorative paper, hot melt melamine resin is used as glue, which has excellent heat resistance, water resistance and chemical resistance, and can significantly improve the physical and mechanical properties of decorative paper. The preparation process of melamine resin glue is as follows:

[0099] 1) Mix melamine resin powder and water in a mass ratio of 1:1.5-2.0, add the mixture into a reaction kettle, and add 1%-2% of the resin mass of NaOH as a catalyst;

[0100] 2) Raise the temperature to 85-95°C, keep warm and stir for 2-3 hours to allow the resin to fully dissolve and undergo a preliminary polycondensation reaction to obtain a primary polycondensate solution with a viscosity of 500-1000 mPa·s;

[0101] 3) Cool down to 60-70°C, add formaldehyde solution (37%) accounting for 30%-50% of the resin mass, continue to keep warm and stir for 1-2 hours to allow the formaldehyde to fully react with the primary polycondensate to form formaldehyde melamine resin;

[0102] 4) Raise the temperature to 85-95°C again, keep stirring for 3-4 hours to promote further polycondensation of the resin and increase the viscosity of the glue to 5000-10000 mPa·s;

[0103] 5) Cool down to 60-70°C, add 1%-3% of the resin mass of a wetting agent and 0.5%-1% of a defoaming agent, stir well, and let stand to degas to obtain a hot melt melamine glue solution that can be used for decorative paper dipping.

[0104] The glue is semi-solid at room temperature and has good storage stability. When used, the glue is heated to 70-80°C to be in a molten state, and the viscosity drops to 500-1000 mPa·s, which is convenient for impregnation of decorative paper.

[0105] After the prepared hot melt melamine glue is heated to a molten state, it is poured into the glue dipping tank, and the glue temperature is controlled to be constant at 70-80°C. Then the decorative paper that has been gravure printed and flexographic printed is continuously passed through the glue dipping tank and immersed in the glue for 5-10 seconds to allow the paper to fully absorb the glue.

[0106] After the decorative paper is dipped in glue, a large amount of excess glue is attached to it when it comes out of the slot. In order to make the glue evenly distributed on the surface of the paper, a pair of horizontally arranged squeezing rollers are used to hydraulically squeeze the paper. The surface of the squeezing roller is covered with a mesh pattern of 25 to 40 meshes / inch, and the relative speed is controlled at 10 to 50 m / min. By adjusting the gap between the squeezing rollers and the line pressure, the liquid retention rate (the ratio of the mass of the attached glue to the mass of the paper) after the paper is dipped in glue is controlled within the range of 100% to 180%.

[0107] In order to completely remove the moisture in the impregnated decorative paper and fully solidify the melamine resin into a film, the paper is dried by combining hot air drying and infrared drying.

[0108] First, the paper enters the hot air circulation drying section. The drying section is equipped with 3 to 5 independently temperature-controlled drying chambers, each equipped with a high-speed circulation fan with a wind speed of no less than 20m / s. The hot air temperature is gradually increased from 130°C to 180°C to fully evaporate the moisture on the surface of the paper. The paper stays in the hot air section for 3 to 5 minutes, and the moisture content is reduced to less than 8% when it leaves the section.

[0109] Then the paper enters the infrared drying section, where a quartz tube short-wave infrared radiator is used to radiate heat to the paper. The radiation power density is not less than 50kW / m2, and the paper stays in the radiation zone for 20 to 40 seconds to fully cross-link and cure the melamine resin, and finally reduce the moisture content of the paper to less than 3%.

[0110] After being impregnated with glue and dried, the toughness and flexural strength of the decorative paper are significantly improved, and its water resistance and dimensional stability are also improved, laying the foundation for subsequent finishing pressing.

[0111] Since the decorative paper after dipping is somewhat brittle, in order to avoid defects such as cracked edges and rough edges during shearing, flexible cutting technology is required to cut it into decorative units of suitable sizes. The key to flexible cutting is to synchronously control the linear speed of the tool and the paper conveying speed, and use ultrasonic vibration to assist cutting.

[0112] The specific process is as follows: the decorative paper after impregnation and drying is continuously conveyed to the flexible cutting machine, and the conveying speed of the paper is accurately controlled by the servo motor. A laser rangefinder sensor is installed above the cutting machine to measure the position of the paper in real time and feed it back to the control system. The system calculates the target linear speed of the circular knife in real time according to the workpiece size and paper position, and controls the servo motor to drive the circular knife to rotate synchronously.

[0113] The circular knife adopts a sharp thin blade design, and the blade thickness does not exceed 0.2mm. In order to reduce the cutting force and cutting burrs, an ultrasonic vibrator is set under the circular knife, with a vibration frequency of 20-40kHz and an amplitude of 5-15μm. Ultrasonic vibration makes the blade vibrate at a high frequency, significantly reducing the instantaneous force and loss during the cutting process.

[0114] During the flexible cutting process, the circular knife and the paper are kept in precise speed synchronization, and the line speed can be dynamically adjusted within the range of 20 to 120 m / min according to the paper characteristics. The dimensional accuracy of the trimmed surface unit is better than ±0.2 mm, the cut is neat and smooth, without defects such as burrs and missing corners, and can meet the requirements of trim pressing.

[0115] In an optional embodiment,

[0116] During the pressing process, the online optical defect detection system performs AI intelligent detection on the surface quality of the panels, and feeds back the defect information to the press control system to adjust the process parameters in real time; the centrally controlled intelligent logistics system, composed of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches the materials of substrates, decorative paper, and finished panels between each processing unit; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks, optimize the balance of production lines, and improve equipment utilization, including:

[0117] A high-resolution linear array CCD camera is installed at the exit section perpendicular to the moving direction of the continuous pressing production line of veneer wood-based panels to collect images of the panel surface. The image data is transmitted to the industrial computer in real time by the image acquisition card. The industrial computer runs a defect detection algorithm software based on a convolutional neural network to preprocess, segment, extract features, and classify and identify the image to determine whether there are defects such as indentations, bubbles, scratches, stains, etc. on the panel surface. The detection results include defect type, size, and coordinate position information.

[0118] The defect detection results are uploaded to the MES system database and input into the press adaptive expert decision module as feedback signals. This module builds a mathematical model of process parameters, defect types and occurrence rates based on machine learning algorithms, evaluates the risk of various defects in combination with real-time detection data streams, and automatically infers dynamic adjustment strategies for process parameters such as oil plate temperature and roller pressure. It generates executable control instructions and sends them to the press PLC, realizing closed-loop optimization control of defect detection feedback and press process parameters.

[0119] The AGV car uses the laser SLAM navigation algorithm to autonomously plan the path and deliver the decorative paper rolls and substrates to the designated production line;

[0120] A six-axis manipulator is used to pick up the finished veneer panels and stack them on the RGV trolley pallet, and the stacking adopts an accordion-style staggered method; the RGV trolley automatically transports the finished products along the track to the front of the vertical warehouse, and then the high-position fork robot transports them into the warehouse; the vertical warehouse uses a combination of fork-type shuttle vehicles and multi-layer elevators, and the inventory data is shared with the production plan of the MES system;

[0121] The warehouse management software automatically generates instructions for picking and dispatching decorative panels according to production tasks and delivery dates, optimizing the allocation of storage and retrieval locations. The operating status data of logistics equipment is transmitted back to the MES system in real time, and scheduling is optimized through status monitoring and efficiency analysis, thereby improving equipment utilization and shortening material turnover time.

[0122] For example, in order to achieve quality monitoring and process optimization of veneer wood-based panels, an online optical defect detection system based on machine vision is integrated into the continuous pressing production line. The system consists of hardware devices such as high-resolution linear array CCD cameras, LED linear light sources, image acquisition cards, and industrial computers, and is equipped with self-developed defect detection algorithm software.

[0123] The system deployment scheme is as follows: At the exit section of the continuous press, the panels pass through the inspection area in sequence, and the linear array camera is installed perpendicular to the direction of panel movement to achieve continuous imaging scanning of the panel surface with a spatial resolution better than 0.1 mm / pixel. The LED linear light source is triggered synchronously with the camera to provide uniform and stable surface lighting. The image data collected by the camera is transmitted to the industrial computer in real time by the image acquisition card, and the adaptive block parallel computing method is used for defect detection and classification recognition.

[0124] The detection algorithm is based on a deep learning convolutional neural network model. The model is trained by annotating a large number of defect sample images offline, so that it can automatically extract the multi-scale texture features of surface defects. During the production process, the detection software preprocesses, segments, extracts features, and classifies the collected images to determine in real time whether there are common defects such as indentations, bubbles, scratches, stains, etc. on the surface of the plate, and accurately locates the coordinates of the defect position. The detection speed is synchronized with the production rhythm of the plate, which can reach 60-120m / min.

[0125] The inspection results include defect type, size, coordinate location and other information, which are automatically recorded by the system and uploaded to the MES system database. At the same time, when serious defects are detected, the system sends an alarm signal to notify the operator to conduct manual re-inspection or isolate defective products.

[0126] In the production process optimization control based on defect detection feedback, the press process parameters are the key control objects. Conventional continuous press control uses PID regulators, which are regulated by single-loop fixed value control according to process parameters such as oil plate temperature, roller pressure and main motor current. However, due to factors such as batch differences between decorative paper and substrates and fluctuations in equipment status, this control method often cannot ensure the stability of product quality.

[0127] To address the above problems, the press control system introduces an adaptive expert decision-making module, which uses defect detection results as feedback to perform intelligent dynamic optimization of press process parameters. Based on a large amount of batch production data, this module uses machine learning algorithms to establish a mathematical model between process parameters and defect types and occurrence rates. Combined with real-time detection data streams, the system evaluates the current risk of various defects, automatically infers the dynamic adjustment strategy of process parameters, and converts it into executable control instructions and sends them to the press PLC.

[0128] For example, when a batch of indentation defects are detected on the surface of the plate, it indicates that the oil pressure plate temperature is too low or the pressure is insufficient. The system makes a timely judgment and increases the oil pressure plate temperature setting value and the pressure roller pressing force accordingly. When bubble defects occur frequently, the system automatically reduces the oil pressure temperature and increases the pressure roller line pressure to avoid excessive cross-linking and curing of the glue due to excessive temperature, which causes stress concentration.

[0129] By combining online defect detection feedback with adaptive expert decision-making, intelligent dynamic optimization and adjustment of the press process parameters are achieved, effectively reducing the incidence of various surface defects and ensuring the quality stability and consistency of the decorative panels from the source.

[0130] Flexible production of veneer wood-based panels requires a high degree of automation and informatization in material distribution and product warehousing. Traditional logistics systems often adopt fixed modes and lack flexibility, which can easily lead to material accumulation or shortage when production rhythm changes, thus restricting production efficiency.

[0131] In order to meet the rapid response requirements of customized production, the veneer production line is equipped with a centrally controlled intelligent logistics system. The system is composed of a variety of logistics equipment, including laser-guided AGV (automatic guided vehicle), six-axis robot, RGV (rail-guided shuttle vehicle), box elevator and high-level shuttle warehouse. The dispatch of various equipment is uniformly managed by the central control system, and data interaction is achieved through the wireless communication network.

[0132] The AGV is responsible for the intelligent delivery of decorative paper rolls and substrates. The onboard controller interacts with the central control system and uses the laser SLAM navigation algorithm to autonomously plan the walking path according to the production plan. The trolley is equipped with an all-round obstacle avoidance sensor and can flexibly bypass obstacles. By deploying AGV intelligent delivery, forklift logistics operations are reduced, labor intensity is reduced, and feeding efficiency is improved.

[0133] Robots and RGV trolleys are used for loading, unloading and transporting finished veneer panels. The six-axis manipulator in the outfeed section picks up the continuously flowing panels and stacks them on the RGV trolley pallet. The palletizing adopts an accordion-style staggered method to maximize the use of the trolley space. The RGV automatically transports the finished panels to the front of the vertical warehouse along a fixed track, and then the high-position fork robot transports them into the warehouse. The vertical warehouse uses a combination of fork shuttles and multi-layer elevators to achieve a storage and access density of more than 120 pallet positions / 100m2.

[0134] The intelligent logistics system is interconnected with the MES system, and inventory data and production plans are shared. According to production tasks and delivery dates, the warehouse management software automatically generates instructions for picking and dispatching panels, optimizes the allocation of cargo spaces, and shortens material turnover time. At the same time, the operating status data of logistics equipment is also transmitted back in real time, which facilitates statistical analysis of equipment utilization and efficiency, taps equipment potential, and optimizes production line balance. Through the flexible scheduling of the intelligent logistics system, material distribution, cache turnover, and finished product warehousing and warehousing in the production of decorative panels have achieved a high degree of automation and information transparency, significantly improving production efficiency and equipment utilization.

[0135] Figure 2 FIG. 1 is a schematic diagram of the structure of a wood-based panel production system based on a digital information platform according to an embodiment of the present invention. Figure 2 As shown, the system comprises:

[0136] The artificial board base is located in the forestry resource-rich area, and is used to process forest resources and plant fiber raw materials into particleboard or fiberboard artificial board base;

[0137] It also includes a printing, dipping and pressing industrial zone centrally arranged with the artificial board substrate base, wherein the printing unit includes a plurality of groups of gravure printing machines for printing base paper to form artificial board facing decorative paper;

[0138] The dipping unit is used to dip the printed wood-based panel decorative paper into hot-melt melamine glue through the dipping tank;

[0139] The pressing unit is used to press the artificial board substrate and the artificial board veneer decorative paper after impregnation with glue at high temperature to form a finished board;

[0140] An intelligent logistics system for centralized production process control, which is used to intelligently and automatically link the equipment of the printing unit, dipping unit and pressing unit;

[0141] The centrally controlled intelligent logistics system, which is composed of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches substrates and finished board materials between processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks.

[0142] The present invention may be a method, an apparatus, a system and / or a computer program product. The computer program product may include a computer-readable storage medium carrying computer-readable program instructions for executing various aspects of the present invention.

[0143] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The wood-based panel production system based on digital information platform is characterized by: include: The artificial board base is located in the forestry resource-rich area, and is used to process forest resources and plant fiber raw materials into particleboard or fiberboard artificial board base; It also includes a printing, dipping and pressing industrial zone centrally arranged with the artificial board substrate base, wherein the printing unit includes a plurality of groups of gravure printing machines for printing base paper to form artificial board facing decorative paper; The dipping unit is used to dip the printed wood-based panel decorative paper into hot-melt melamine glue through the dipping tank; The pressing unit is used to press the artificial board substrate and the artificial board veneer decorative paper after impregnation with glue at high temperature to form a finished board; The intelligent logistics system with centralized production process control is used to realize intelligent and automated linkage of the equipment of the printing unit, the dipping unit and the pressing unit.

2. The system according to claim 1, characterized in that The gravure printing unit adopts synchronous transmission technology to ensure high-precision alignment of various color printing patterns; The printing process uses environmentally friendly water-based ink, which is then dried by infrared rays and then printed on the surface using a flexographic printing process. A layer of wear-resistant protective coating includes: During the gravure printing process, environmentally friendly water-based ink is printed on the base paper. The water-based ink uses water as a dispersion medium and is prepared by adding resin, colorant and additives to water. The base paper printed with the water-based ink then passes through an infrared drying unit, where it is directly heated by infrared radiation and quickly dried at 50-60°C, reducing the residual moisture in the ink layer to less than 3%. The dried base paper is then printed with a layer of wear-resistant protective coating on the surface through a flexographic printing process. Flexographic printing uses a flexible resin plate, and the coating ink is composed of UV-curable resin, nano-aluminum oxide particles and additives. During the flexographic printing process, the printing pressure and dot area coverage are precisely controlled, and the coating is cured with a GaN-based UV LED lamp to form a surface coating with excellent hardness and flexibility. The coating thickness is 20-30μm, and the surface hardness is not less than 4H.

3. The system according to claim 1, characterized in that The system further comprises: Passing the decorative base paper through a plurality of sequentially arranged gravure printing units in sequence, wherein in each gravure printing unit, the base paper contacts a gravure roller provided with a printing pattern of different colors and transfers the pattern; Multiple groups of gravure printing units adopt a synchronous transmission control system, which includes a rotary encoder, a servo motor and its driver, and a central synchronous controller arranged at the end of each gravure roller shaft; The synchronous controller sends control instructions to each servo driver in real time through industrial Ethernet according to the target speed curve of each gravure roller that needs to rotate synchronously, combined with the feedback signal of the rotary encoder, to accurately control the rotation speed and phase of each gravure roller, thereby achieving high-precision alignment of printed patterns of different colors.

4. The system according to claim 1, characterized in that The system also includes: a decorative paper dipping unit, which immerses the printed decorative paper into hot-melt melamine glue through a dipping tank, and after saturated absorption, controls the uniformity of glue distribution through a squeeze roller, and then uses a hot air and infrared combined drying process to solidify the glue into a film.

5. The system according to claim 4, characterized in that The system further comprises: The melamine resin powder is mixed with water and a catalyst, and the mixture is stirred and kept warm at 85°C to dissolve the resin and perform preliminary polycondensation, and then a formaldehyde solution is added to continue the reaction to obtain a formaldehyde melamine resin; the mixture is heated and kept warm again to promote further polycondensation of the resin to obtain a glue solution with a viscosity of 10000 mPa·s, and a wetting agent and a defoaming agent are added after cooling to obtain a hot melt melamine glue solution which is semi-solid at room temperature; The hot melt melamine glue solution is heated to a molten state and poured into a dipping tank, and the temperature of the glue solution is controlled to be constant at 70-80° C. The decorative paper after gravure printing and flexographic printing is continuously passed through the dipping tank for dipping and absorption, and then a pair of squeezing rollers with mesh surfaces are used to hydraulically squeeze the paper, and the gap between the squeezing rollers and the line pressure are adjusted to control the liquid holding rate of the paper within the range of 100%-180%; The impregnated paper is dried by combining hot air drying and infrared drying. The hot air drying section is equipped with multiple independently temperature-controlled drying chambers, and the hot air temperature increases step by step from 130°C to 180°C. The infrared drying section uses quartz tube short-wave infrared radiators to radiate heating to the paper, and the radiation power density is not less than 50kW / m2, ultimately reducing the moisture content of the paper to below 3%.

6. The system according to claim 1, characterized in that The decorative paper after impregnation is then cut into facing units matching the size of the substrate by a flexible cutting unit, including: The decorative paper that has been impregnated and dried is transported to a flexible cutting machine equipped with a laser ranging sensor. The control system measures the paper position in real time and calculates the target linear speed of the circular knife. The servo motor drives the rotation of the circular knife in synchronization with the paper transportation. The circular knife adopts a thin blade design with a thickness of no more than 0.2mm, and an ultrasonic vibrator is set underneath it with a frequency of 2040kHz and an amplitude of 515μm. The circular knife and the paper maintain dynamic speed synchronization, and the linear speed range is 20 to 120m / min.

7. The system according to claim 1, characterized in that During the pressing process, the surface quality of the panels is tested by an online optical defect detection system using AI intelligent detection, and the defect information is fed back to the press control system to adjust the process parameters in real time. The centrally controlled intelligent logistics system, which consists of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches substrates, decorative paper, and finished panels between processing units. The logistics system interacts with the MES system to flexibly schedule materials according to production tasks, optimize production line balance, and improve equipment utilization.

8. The system according to claim 7, characterized in that The system further comprises: A high-resolution linear array CCD camera is installed at the exit section perpendicular to the moving direction of the continuous pressing production line of veneer wood-based panels to collect images of the panel surface. The image data is transmitted to the industrial computer in real time by the image acquisition card. The industrial computer runs a defect detection algorithm software based on a convolutional neural network to preprocess, segment, extract features, and classify and identify the image to determine whether there are defects such as indentations, bubbles, scratches, and stains on the panel surface. The detection results include defect type, size, and coordinate position information. The defect detection results are uploaded to the MES system database and input into the press adaptive expert decision module as feedback signals. This module builds a mathematical model of process parameters, defect types and occurrence rates based on a machine learning algorithm, and evaluates the risk of various defects in combination with real-time detection data streams. It automatically infers the dynamic adjustment strategy of the process parameters such as the oil plate temperature and the roller pressure, and generates executable control instructions that are sent to the press PLC, thus realizing closed-loop optimization control of defect detection feedback and press process parameters.

9. The system according to claim 8, characterized in that The system further comprises: The centrally controlled intelligent logistics system consists of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, which automatically transport and cache the materials of substrates and finished boards between various processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks; the AGV cart uses the laser SLAM navigation algorithm to autonomously plan the path and deliver the decorative paper rolls and substrates to the designated production line; A six-axis manipulator is used to pick up the finished veneer panels and stack them on the RGV trolley pallet, and the stacking adopts an accordion-style staggered method; the RGV trolley automatically transports the finished products along the track to the front of the vertical warehouse, and then the high-position fork robot transports them into the warehouse; the vertical warehouse uses a combination of fork-type shuttle vehicles and multi-layer elevators, and the inventory data is shared with the production plan of the MES system; The warehouse management software automatically generates instructions for picking and dispatching decorative panels according to production tasks and delivery dates, optimizing the allocation of storage and retrieval locations. The operating status data of logistics equipment is transmitted back to the MES system in real time, and scheduling is optimized through status monitoring and efficiency analysis, thereby improving equipment utilization and shortening material turnover time.

10. A method for producing wood-based panels based on a digital information platform, used for application in the system described in any one of claims 1 to 9, characterized in that: include: The artificial board substrate preparation unit arranged in the forestry resource-rich area is used to process the plant fiber raw materials of wood into the substrate of particleboard or fiberboard; The printed decorative paper is immersed in hot melt melamine glue through a dipping tank. After saturated absorption, the glue is evenly distributed through a squeeze roller, and then the glue is cured into a film by a combined drying process of hot air and infrared rays. The dipped decorative paper is then cut into facing units that match the size of the substrate by a flexible cutting unit. The substrate is automatically positioned and accurately transported to the continuous press, where the veneer and substrate are firmly bonded through the oil pressure process; The centrally controlled intelligent logistics system, which is composed of AGV carts, robots, RGV carts, elevators, and automated vertical warehouse logistics equipment, automatically transports and caches substrates and finished board materials between processing units; the logistics system interacts with the MES system to flexibly dispatch materials according to production tasks.

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