An apparatus for drying a thick paper faced gypsum board

Abstract

The utility model relates to the technical field of gypsum board production equipment, concretely relates to a device for drying thick paper faced gypsum board, including drying box, heating case, dehumidification system, two -way penetration drying module, heating case, dehumidification system set up at drying box outside, two -way penetration drying module sets up in drying box, including upper pressure plate, lower pressure plate, positive pressure air duct and negative pressure air duct, upper pressure plate is opposite with lower pressure plate and is all hollow structure, and the opposite surface is uniformly provided with micropore, positive pressure air duct communicates upper pressure plate with heating case, is used for injecting hot air to the upper surface of gypsum board, negative pressure air duct communicates lower pressure plate with dehumidification system, is used for sucking the damp hot air from the lower surface of gypsum board, the pressure difference formed by positive pressure air duct and negative pressure air duct drives hot air vertical penetration gypsum board, the utility model can drive hot flow vertical penetration gypsum board, eliminates drying stress difference, prevents the deformation cracking of board material.

Description

Technical Field

[0001] This utility model relates to the technical field of gypsum board production equipment, specifically to a device for drying thick paper-faced gypsum board. Background Technology

[0002] Thick paper-faced gypsum board (thickness ≥ 25mm) is widely used in high-end buildings due to its excellent fire resistance and sound insulation properties. During its production, the drying process significantly impacts the quality of the finished product. Traditional drying devices often employ unidirectional hot air circulation. For example, patent CN222747667U discloses a drying device for ultra-thick paper-faced gypsum board, where hot air penetrates from one side of the gypsum board surface. However, limited by the board thickness, the hot air cannot effectively penetrate the internal layered structure, leading to the following defects:

[0003] 1. Uneven drying: The surface moisture evaporates quickly to form a hard shell, which hinders the migration of internal moisture. The moisture content of the central layer is often higher than 8% (the standard requires ≤5%), which leads to deformation later.

[0004] 2. Energy waste: To compensate for insufficient penetration, drying time needs to be extended or temperature increased (above 120℃), increasing energy consumption by more than 30%;

[0005] 3. Efficiency bottleneck: Unidirectional air supply can only achieve 40%-50% effective utilization of heat energy, and the drying cycle of ultra-thick plates is as long as 60 minutes or more.

[0006] Existing improvement solutions (such as circulating dehumidification and rotary drying) improve hot air utilization, but they do not solve the problem of hot air penetration failure in the thickness direction. There is an urgent need for a drying structure that can drive the heat flow to penetrate vertically through the entire thickness of the gypsum board. Utility Model Content

[0007] In view of this, the purpose of this utility model is to provide an apparatus for drying thick paper-faced gypsum board, so as to solve the problems mentioned in the background art.

[0008] To achieve the above objectives, this utility model provides the following technical solution:

[0009] An apparatus for drying thick paper-faced gypsum board includes a drying chamber, a heating chamber, a dehumidification system, and a bidirectional penetration drying module. The heating chamber and dehumidification system are located outside the drying chamber. The bidirectional penetration drying module is located inside the drying chamber and includes an upper pressure plate, a lower pressure plate, a positive pressure air duct, and a negative pressure air duct. The upper and lower pressure plates are arranged opposite each other and are both hollow structures with micropores evenly distributed on their opposing surfaces. The positive pressure air duct connects the upper pressure plate and the heating chamber and is used to inject hot air into the upper surface of the gypsum board. The negative pressure air duct connects the lower pressure plate and the dehumidification system and is used to draw humid and hot air from the lower surface of the gypsum board. The pressure difference formed by the positive and negative pressure air ducts drives the hot air to penetrate the gypsum board vertically.

[0010] As a further embodiment of this utility model, the dehumidification system is a rotary dehumidifier.

[0011] As a further embodiment of this utility model: hydraulic cylinders are respectively provided on both sides of the upper pressure plate, one end of the hydraulic cylinder is connected to the top wall inside the drying chamber, and the other end is connected to the upper surface of the upper pressure plate, and a pressure sensor is installed on the lower surface of the upper pressure plate.

[0012] As a further embodiment of this utility model: The drying chamber has a feeding conveyor belt and a discharging conveyor belt running through its two side walls respectively; the lower pressure plate has an electric push rod and a support frame rotatably connected to both ends respectively; the other end of the electric push rod is rotatably connected to one side of the bottom wall of the drying chamber, and the other end of the support frame is fixedly connected to the other side of the bottom wall of the drying chamber; by extending the electric push rod, one end of the lower pressure plate can be raised, causing the gypsum board conveyed to the lower pressure plate by the feeding conveyor belt to slide down to the discharging conveyor belt.

[0013] As a further improvement of this utility model, the positive pressure air duct and the negative pressure air duct are respectively connected to the upper pressure plate and the lower pressure plate via corrugated flexible hoses.

[0014] As a further improvement of this utility model, the negative pressure air duct is connected to the dehumidification system via an exhaust fan.

[0015] As a further embodiment of this utility model, it also includes a PLC controller and an electrode plate connected to the PLC controller. The PLC controller sets the pressure difference between the positive and negative pressure air ducts, the hot air temperature, and the drying time according to the thickness of the gypsum board. The electrode plate is embedded in the upper surface of the lower pressure plate and is used to monitor the change in the resistance value of the gypsum board in real time.

[0016] By adopting the above technical solution, this utility model will have the following beneficial effects:

[0017] The uniform micropores on the surfaces of the upper and lower pressure plates allow hot air to penetrate simultaneously from both the upper and lower surfaces of the gypsum board, completely eliminating the surface hardening phenomenon caused by unidirectional air supply and ensuring efficient migration of moisture from the inside to both sides. The synergistic effect of the hot air injected by the positive pressure air duct and the moisture drawn by the negative pressure air duct forms a forced airflow that penetrates the entire thickness of the gypsum board vertically, solving the technical bottleneck that hot air cannot reach the core layer of ultra-thick boards. Furthermore, because the hot air penetrates in a straight line along the thickness direction, it avoids the heat loss caused by the retention of traditional circulating hot air on the surface of the gypsum board, significantly improving the effective utilization rate of heat energy.

[0018] Compared with existing technologies, the bidirectional penetration mechanism of this utility model enables the surface and core layers of gypsum board to dehydrate simultaneously, eliminating differences in drying stress, preventing board deformation and cracking, and ensuring that the finished product has a consistent moisture content distribution that meets industrial-grade standards. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the device for drying thick paper-faced gypsum board according to an embodiment of the present invention in its working state;

[0021] Figure 2 for Figure 1 A schematic diagram of the apparatus for drying thick paper-faced gypsum board as described in the embodiment, showing the structure after drying is completed;

[0022] Figure 3 for Figure 1 A cross-sectional view of the bidirectional penetration drying module in operation;

[0023] The correspondence between the labels and component names in the attached figures is as follows:

[0024] 1. Drying oven; 2. Heating oven; 3. Rotary dehumidifier; 41. Upper pressure plate; 42. Lower pressure plate; 43. Positive pressure air duct; 44. Negative pressure air duct; 45. Corrugated hose; 5. Gypsum board; 6. Hydraulic cylinder; 61. Pressure sensor; 71. Feed conveyor belt; 72. Discharge conveyor belt; 73. Electric push rod; 74. Support frame; 8. Exhaust fan; 9. Electrode plate. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0026] Please refer to Figure 1-3 In one embodiment of the device for drying thick paper-faced gypsum board provided by this utility model, the device includes a drying chamber 1, a heating chamber 2, a dehumidification system, and a bidirectional penetration drying module. The heating chamber 2 and the dehumidification system are disposed outside the drying chamber 1; the bidirectional penetration drying module is disposed inside the drying chamber 1 and includes an upper pressure plate 41, a lower pressure plate 42, a positive pressure air duct 43, and a negative pressure air duct 44.

[0027] Both the upper pressure plate 41 and the lower pressure plate 42 are made of stainless steel and are positioned opposite each other. Both are hollow structures, and their opposing surfaces are laser-drilled to form uniformly distributed micropores (the pore size meets the requirements for hot air penetration). The positive pressure air duct 43 connects the upper pressure plate 41 and the heating box 2, and is used to inject hot air (temperature 80-120℃, pressure 0.5-2 kPa) onto the upper surface of the gypsum board 5. One end of the negative pressure air duct 44 is connected to the lower pressure plate 42, and the other end is connected to the dehumidification system through the exhaust fan 8 to maintain a negative pressure of -0.3 to -1 kPa, which is used to draw humid and hot air from the lower surface of the gypsum board 5. The pressure difference formed by the positive pressure air duct 43 and the negative pressure air duct 44 drives the hot air to penetrate the gypsum board 5 vertically.

[0028] As a preferred embodiment, the dehumidification system is a rotary dehumidifier 3. The rotary dehumidifier 3 is an existing high-efficiency and stable industrial-grade dehumidification device. Its rotor is divided into two fan-shaped areas by a sealed partition, which are used to dry and adsorb humid air and to dehydrate and regenerate when saturated. The rotor rotation design achieves simultaneous adsorption and regeneration, eliminating the need to stop the machine for regeneration and ensuring continuous dehumidification for 24 hours, thus avoiding interruption of the production process.

[0029] As a preferred embodiment, hydraulic cylinders 6 are respectively provided on both sides of the upper pressure plate 41. One end of the hydraulic cylinder 6 is connected to the inner top wall of the drying box 1, and the other end is connected to the upper surface of the upper pressure plate 41. The extension and retraction of the hydraulic cylinder 6 drives the upper pressure plate 41 to cooperate with the lower pressure plate 42 to clamp the gypsum board 5. A pressure sensor 61 is installed on the lower surface of the upper pressure plate 41 to detect the clamping force in real time (range 10-30 kN). When the limit is exceeded, the hydraulic system automatically releases pressure.

[0030] As a preferred embodiment, the drying chamber 1 has a feeding conveyor belt 71 for feeding gypsum board 5 and a discharging conveyor belt 72 for discharging gypsum board 5 through its two side walls. The feeding conveyor belt 71 is flush with the lower pressure plate 42, and the discharging conveyor belt 72 is located diagonally below the lower pressure plate 42. The lower pressure plate 42 is rotatably connected to an electric push rod 73 and a support frame 74 at both ends. The other end of the electric push rod 73 is rotatably connected to one side of the bottom wall of the drying chamber 1, and the other end of the support frame 74 is fixedly connected to the other side of the bottom wall of the drying chamber 1. By extending the electric push rod 73, one end of the lower pressure plate 42 can be raised, so that the gypsum board 5 conveyed by the feeding conveyor belt 71 to the lower pressure plate 42 slides down to the discharging conveyor belt 72, making it convenient to replace the gypsum board 5.

[0031] As a preferred embodiment, the positive pressure duct 43 and the negative pressure duct 44 are respectively connected to the upper pressure plate 41 and the lower pressure plate 42 through corrugated hoses 45. The corrugated hoses 45 are made of stainless steel, and both ends are sealed to the duct interface and the hollow cavity of the pressure plate through flanges with sealing gaskets. The corrugated hoses 45 can expand and contract synchronously with the upper pressure plate 41 and bend synchronously with the lower pressure plate 42 without excessive stretching or wrinkling, thus maintaining the unobstructed flow of the duct.

[0032] As a preferred embodiment, the system also includes a PLC controller and an electrode plate 9 connected to the PLC controller. The thickness of the gypsum board 5 (15 / 18 / 25mm) is input, and the PLC controller automatically matches the pressure difference, temperature, and drying time (e.g., for a 25mm board, ΔP=1.5kPa, T=105℃, t=35min). The electrode plate 9 is embedded in the upper surface of the lower pressure plate 42 and is used to monitor the resistance value of the gypsum board 5 in real time (moisture content ↓ → resistance ↑). When the rate of increase in resistance value slows down (ΔR / Δt<5Ω / min), the moisture content is determined to be ≤1.5%, and the drying process is terminated.

[0033] The method of use or working principle of this utility model is as follows:

[0034] I. Clamping and Positioning Stage

[0035] Feeding and fixing: The ultra-thick gypsum board 5 (thickness ≥ 25mm) is conveyed to the upper surface of the lower pressure plate 42 by the feeding conveyor belt 71; the hydraulic cylinder 6 drives the upper pressure plate 41 to press down, and the pressure sensor 61 provides real-time feedback of the clamping force to ensure that the board is stably attached to the microporous surface and avoid pressure damage.

[0036] II. Two-way hot air penetration stage

[0037] Pressure difference generation: Hot air is injected into the positive pressure duct 43 (airflow direction: heating box 2 → positive pressure duct 43 → upper pressure plate 41 micro-holes); the negative pressure duct 44 is activated by the exhaust fan 8 to draw in air (airflow direction: lower pressure plate 42 micro-holes → negative pressure duct 44 → dehumidification system);

[0038] Key principle: Positive and negative pressure work together to form a vertical pressure gradient, driving hot air to penetrate the internal layered structure of the gypsum board in a straight line.

[0039] Moisture migration mechanism: Hot air is forced to penetrate the pores of the board, causing the internal moisture to vaporize rapidly; the hot and humid steam is directionally drawn away by negative pressure to the dehumidification system, avoiding condensation and back-seepage on the surface.

[0040] III. Dehumidification and Regeneration Stage

[0041] Humid and hot air enters the rotary dehumidifier 3. The rotary dehumidifier 3 operates synchronously in two zones for moisture absorption and regeneration, achieving continuous dehumidification with zero downtime. The dry hot air is returned to the heating box 2 for recycling, and the saturated moisture is discharged through the exhaust pipe.

[0042] IV. Intelligent Control and Termination Phase

[0043] Parameter adaptive: The PLC controller automatically sets the pressure difference between the positive pressure air duct 43 and the negative pressure air duct 44, the hot air temperature and the drying time according to the input thickness of the gypsum board 5;

[0044] Moisture feedback control: The electrode plate 9 embedded in the lower pressure plate 42 monitors the resistance value of the gypsum board 5 in real time (the less moisture in the gypsum board 5, the greater the resistance value); when the resistance change rate ΔR / Δt < 5Ω / min (corresponding to a moisture content ≤ 1.5%), the drying is determined to be complete;

[0045] Discharge: Hydraulic cylinder 6 lifts one end of the lower pressure plate 42, causing the gypsum board 5 to slide down to the discharge conveyor belt 72 to output the finished product.

[0046] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. An apparatus for drying thick paper-faced gypsum board, comprising a drying chamber (1), a heating chamber (2) disposed outside the drying chamber (1), and a dehumidification system, characterized in that, It also includes a bidirectional penetration drying module installed in the drying box (1). The bidirectional penetration drying module includes an upper pressure plate (41), a lower pressure plate (42), a positive pressure air duct (43), and a negative pressure air duct (44). The upper pressure plate (41) and the lower pressure plate (42) are arranged opposite to each other and are both hollow structures with micropores evenly distributed on their opposing surfaces. The positive pressure air duct (43) connects the upper pressure plate (41) and the heating box (2) and is used to inject hot air into the upper surface of the gypsum board (5). The negative pressure air duct (44) connects the lower pressure plate (42) and the dehumidification system and is used to draw humid and hot air from the lower surface of the gypsum board (5). The pressure difference formed by the positive pressure air duct (43) and the negative pressure air duct (44) drives the hot air to penetrate the gypsum board (5) vertically.

2. The apparatus for drying thick paper-faced gypsum board according to claim 1, characterized in that, The dehumidification system is a rotary dehumidifier (3).

3. The apparatus for drying thick paper-faced gypsum board according to claim 1, characterized in that, Hydraulic cylinders (6) are provided on both sides of the upper pressure plate (41). One end of the hydraulic cylinder (6) is connected to the inner top wall of the drying box (1), and the other end is connected to the upper surface of the upper pressure plate (41). A pressure sensor (61) is installed on the lower surface of the upper pressure plate (41).

4. The apparatus for drying thick paper-faced gypsum board according to claim 3, characterized in that, The drying box (1) has a feeding conveyor belt (71) and a discharging conveyor belt (72) running through its two side walls respectively; the lower pressure plate (42) is rotatably connected to an electric push rod (73) and a support frame (74) at both ends respectively; the other end of the electric push rod (73) is rotatably connected to one side of the bottom wall of the drying box (1), and the other end of the support frame (74) is fixedly connected to the other side of the bottom wall of the drying box (1); by extending the electric push rod (73), one end of the lower pressure plate (42) can be raised, so that the gypsum board (5) conveyed by the feeding conveyor belt (71) to the lower pressure plate (42) slides down to the discharging conveyor belt (72).

5. The apparatus for drying thick paper-faced gypsum board according to claim 4, characterized in that, The positive pressure duct (43) and negative pressure duct (44) are respectively connected to the upper pressure plate (41) and the lower pressure plate (42) through corrugated hoses (45).

6. The apparatus for drying thick paper-faced gypsum board according to claim 1, characterized in that, The negative pressure duct (44) is connected to the dehumidification system via the exhaust fan (8).

7. The apparatus for drying thick paper-faced gypsum board according to claim 1, characterized in that, It also includes a PLC controller and an electrode plate (9) connected to the PLC controller. The PLC controller sets the pressure difference between the positive pressure air duct (43) and the negative pressure air duct (44), the hot air temperature and the drying time according to the thickness of the gypsum board (5). The electrode plate (9) is embedded in the upper surface of the lower pressure plate (42) and is used to monitor the change in the resistance value of the gypsum board (5) in real time.

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