A flame-retardant foaming ball shunt spraying system for fiberboard

Abstract

The present invention provides a flame-retardant foamed ball shunt spraying system for fiberboards, which includes a shunt device and a spraying device. The shunt device includes a foamed ball silo, a spiral feeder, a distribution silo, and a foamed ball blanking pipe; the spraying device includes a pneumatic conveying component, a spraying component, and a return air collection component. The middle of the pneumatic conveying hose of the pneumatic conveying component is connected with a flame-retardant foamed ball blanking pipe; the space formed between the inner wall and the outer wall of the spraying pipe of the spraying component is a return air collection chamber; each foamed ball nozzle is penetrated through the spraying pipe, and both ends of each foamed ball acceleration pipe are respectively connected with the pneumatic conveying hose and the foamed ball nozzle; and a plurality of air vent holes are distributed on the pipe wall of each foamed ball nozzle; bearings are sleeved at both ends of the spraying pipe. The present invention can control the spraying of foamed balls to each cross-section position of the cross-section layer of the fiberboard, reduce the density of the board, and at the same time, the positions of the foamed balls on the cross-section of the board are not on a straight line, enhancing the side nail holding force of the board, and at the same time, the board is not easily deformed.

Description

Technical Field

[0001] The present invention relates to a flame-retardant foaming ball shunt spraying system for fiberboard. Background Art

[0002] Fiberboard is a kind of artificial board mainly made of wood fiber or other plant fibers. After fiber preparation, adhesives are applied, the fibers are dried and then paved into a mold, and finally it is made by hot pressing. Classified by bulk density, fiberboard can be divided into high-density fiberboard, medium-density fiberboard, and low-density fiberboard. Due to the uniform material of fiberboard, it is widely used in the processing of furniture, floors, wall panels, packaging boxes, ceilings, etc. After more than 40 years of development of fiberboard manufacturing technology, the production process technology has reached its limit and cannot significantly improve the physical and mechanical properties of fiberboard sheets. Especially in the development of lightweight fiberboard at low density, it is impossible to produce high-performance flame-retardant boards with a density less than 500 kg / M3.

[0003] With the improvement of living standards, people's safety awareness has also increased. Medium and low-density fiberboard not only needs to meet the original physical and mechanical indexes, but also needs to have sufficient flame-retardant ability and lightness. In the production of existing flame-retardant lightweight fiberboard, it is difficult to prepare lightweight flame-retardant boards with a density of 450 kg / m³ - 490 kg / m³. The main reason is that in this density range, the physical and mechanical properties of the board are positively correlated with the board density. At the same time, due to the relatively large density of the flame retardant, it is more difficult to reduce the board density. The existing solution is to uniformly add a flame retardant and a flame-retardant foaming agent to the dry fibers after sizing and drying to reduce the average density of the fiberboard.

[0004] The defect of this method is that the surface sanding layer of the fiberboard contains foaming ball particles. After sanding off the pre-cured layer on the surface with foaming ball particles, large-area irregular pits appear on the board, which affects the subsequent decoration and aesthetics of the board. To solve this problem, the existing method is to use a two-layer fiber paving method, laying the foaming balls in the middle, which solves the problem that the fiber sanding surface layer contains foaming ball particles, but there are still two problems. One is that since the middle layer is foaming balls, it causes the board to be hollow and the physical and mechanical property indexes such as the lateral nail-holding force are insufficient; the other is that when the foaming ball particles overlap or the particle sizes are uneven, the fiber layer density of the fiberboard sheet is seriously unbalanced, which is likely to cause the board to deform. There is no device that combines the spraying device of foaming ball particles and the fiber paving device available on the market, so that the foaming ball particles can be sprayed to each cross-section position of the fiberboard cross-section layer to reduce the board density. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a flame-retardant foaming ball shunt spraying system for fiberboard, which can control the spraying of foaming balls to each cross-section position of the cross-section layer of the fiberboard, reduce the density of the board, and at the same time, the positions of the foaming balls on the cross-section of the board are not in a straight line, enhancing the side nail-holding force of the board and making the board not easily deformed.

[0006] The present invention is implemented as follows:

[0007] A flame-retardant foaming ball shunt spraying system for fiberboard includes a shunt device and a spraying device. The shunt device includes a foaming ball silo, a screw feeder, a distribution bin, and a foaming ball feeding pipe. A screw feeder is arranged at the outlet of the foaming ball silo, the outlet of the screw feeder is arranged above the distribution bin, and the foaming ball feeding pipe is connected to the lower part of the distribution bin;

[0008] In the distribution bin, a material dividing plate, a distribution plate, a plurality of metering bins, and a flow limiting plate are arranged in sequence from top to bottom. The distribution plate is distributed with first through holes, and the inlets of the metering bins are connected to the corresponding first through holes; the flow limiting plate is distributed with second through holes, and the outlets of the metering bins are connected to the corresponding second through holes; the lower ends of the second through holes are connected to the corresponding foaming ball feeding pipes;

[0009] The spraying device includes a pneumatic conveying component, a spraying component, and a return air collection component. The pneumatic conveying component includes a fan, an air box, a pneumatic conveying hose, and an air volume regulating valve. The fan is connected to the air inlet of the air box, and a plurality of pneumatic conveying hoses are connected to the air outlet of the air box. An air volume regulating valve is arranged on each pneumatic conveying hose; a foaming ball feeding pipe is connected to the middle of each pneumatic conveying hose;

[0010] The spraying component includes a spraying pipe, a plurality of foaming ball accelerating pipes, and a plurality of foaming ball nozzles. Each foaming ball accelerating pipe is arranged inside the spraying pipe, and the space formed between the inner wall and the outer wall of the spraying pipe is a return air collection chamber; one end of each foaming ball accelerating pipe is respectively connected to the corresponding pneumatic conveying hose, each foaming ball nozzle is penetrated through the spraying pipe, the inlet of each foaming ball nozzle is connected to the corresponding foaming ball accelerating pipe, and the outlet of each foaming ball nozzle extends to the outside of the spraying pipe; and a plurality of air holes are distributed on the pipe wall of each foaming ball nozzle; bearings are sleeved at both ends of the spraying pipe, and the two bearings are both fixed on the trolley;

[0011] The return air collection assembly includes a return air collection pipe, a return air main pipe, a return air valve, an air inlet pipe, and an air inlet valve. The return air collection pipe is communicated with the return air collection chamber, and the other end of the return air collection pipe is connected to the return air main pipe. The return air main pipe is connected to the middle of the air inlet pipe. The outlet end of the air inlet pipe is connected to a fan. The return air valve is arranged on the return air main pipe, and the air inlet valve is arranged at the inlet end of the air inlet pipe.

[0012] Further, a vibrator is also arranged outside the distribution bin.

[0013] Further, a first handle is arranged at one end of the distribution plate, and a second handle is arranged at one end of the current-limiting plate. Two installation grooves are arranged in the distribution bin. One end of each installation groove penetrates the side wall of the distribution bin. The distribution plate and the current-limiting plate are detachably arranged in the installation grooves, and the first handle and the second handle extend outside the side wall of the distribution bin.

[0014] Further, each metering bin includes a cylindrical upper part and a conical lower part arranged up and down, and the inlet diameter of the metering bin is larger than the outlet diameter of the metering bin.

[0015] Further, chamfers are arranged on the upper and lower edges of the first through hole and the upper edge of the second through hole.

[0016] Further, the diameter of the first through hole is 3-5 mm, and the diameter of the second through hole is 3-4 mm.

[0017] Further, the maximum angle at which the spraying pipe can rotate back and forth along the bearings at both ends is 15°.

[0018] Further, the included angle between each foaming ball nozzle and the vertical line of the spraying pipe is -110° to +110°.

[0019] Further, the lengths of the foaming ball nozzles increase in sequence from bottom to top along the spraying pipe.

[0020] The present invention has the following advantages:

[0021] 1. The flame-retardant foaming ball spraying device of the present invention can control the spraying of foaming balls to each cross-section position of the cross-section layer of the fiberboard, reduce the density of the board, and can also realize the simultaneous spraying of foaming balls at different angles in the front and back, below, flat shooting, parabolic shooting, left and right moving shooting, free fall, downward semi-circular mode, etc. The positions of the foaming particles on the cross-section of the board are not on a straight line, which enhances the side nail-holding force of the board, and at the same time, the board is not easily deformed; and there are no large-area irregular pits on the board, which does not affect the subsequent decoration and aesthetics of the board.

[0022] 2. The lightweight flame-retardant fiberboard produced by using the present invention has a balanced fiber layer density in the fiberboard sheet produced under the same production process conditions, is not easily deformed, and can meet the physical and mechanical property indexes such as the side nail-holding force of the sheet. The lightweight flame retardancy meets the requirements of Class B and Class C flame-retardant boards specified in the national standard GB8624-2006 "Classification of the Burning Performance of Building Materials and Products". That is, it meets the performance requirement indexes for use in the lightweight fiberboard industry under dry conditions in the lightweight fiberboard standard with a density of 450 to 490 kg / m³, and also meets the requirements of the national Class C flame-retardant fireproof board for lightweight flame retardancy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be further described below with reference to the accompanying drawings in conjunction with embodiments.

[0024] Figure 1 It is a schematic diagram of a flame-retardant foaming ball shunt spraying system for a fiberboard of the present invention.

[0025] Figure 2 It is a schematic diagram of the cooperation between a flame-retardant foaming ball shunt spraying system for a fiberboard of the present invention and a fiber laying device.

[0026] Figure 3 It is a schematic diagram of the leveling roller structure of the present invention.

[0027] Figure 4 It is a side view of the spraying assembly of the present invention.

[0028] Figure 5 It is a cross-sectional view of the foaming ball nozzle of the present invention.

[0029] Figure 6 It is a schematic diagram of the structure of the material distribution plate in the embodiment of the present invention.

[0030] Figure 7 It is a cross-sectional view of the distribution plate in the embodiment of the present invention.

[0031] Figure 8 It is a top view structural schematic diagram of the distribution plate in the embodiment of the present invention.

[0032] Figure 9 It is a schematic diagram of the structure of the flow-limiting plate in the embodiment of the present invention.

[0033] Figure 10 It is a side view of the dry fiberboard blank produced by the present invention.

[0034] Figure 11 It is an effect diagram of the foaming ball in the dry fiberboard blank produced by the present invention expanding and filling the groove after foaming. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] Refer to Figures 1-11, the present invention relates to a flame-retardant foamed ball shunt spraying system for fiberboard, which includes a shunt device 2 and a spraying device 3, and can also cooperate with a fiber paving device 1. The fiber paving device includes a fiber feeding bin 11, a discharge conveyor belt 12, a dispersing roller 13, a paving bin 14, a slab conveyor belt 15, and a leveling roller 16. The discharge conveyor belt 12 is arranged at the bottom of the fiber feeding bin 11, and a paving rake 17 is also arranged above the discharge conveyor belt 12. A plurality of the dispersing rollers 13 are arranged at the discharge port of the fiber feeding bin 11. The slab conveyor belt 15 is arranged at the bottom of the paving bin 14 and extends outside the outlet of the paving bin 14. The leveling roller 16 is arranged at the outlet of the paving bin 14 and is located above the slab conveyor belt 15. Short bundle teeth 161 and long bundle teeth 162 are distributed on the leveling roller 16, and the length of the long bundle teeth 162 is longer than that of the short bundle teeth 161. The length of the long bundle teeth 162 is 40 - 60 mm longer than the length of the short bundle teeth 161.

[0036] The shunt device 2 includes a foamed ball bin 21, a screw feeder 22, a distribution bin 23, and a foamed ball blanking pipe 24. A screw feeder 22 is arranged at the outlet of the foamed ball bin 21, and the outlet of the screw feeder 22 is arranged above the distribution bin 23. The foamed ball blanking pipe 24 is connected to the lower flow-limiting plate 234 of the distribution bin 23.

[0037] In the distribution bin 23, a material dividing plate 231, a distribution plate 232, a plurality of metering bins 233, and a flow-limiting plate 234 are arranged in sequence from top to bottom. First through holes 2321 are distributed on the distribution plate 232, and the inlets of the metering bins 233 are communicated with the corresponding first through holes 2321. Second through holes 2341 are distributed on the flow-limiting plate 234, and the outlets of the metering bins 233 are communicated with the corresponding second through holes 2341. The lower ends of the second through holes 2341 are connected to the corresponding foamed ball blanking pipes 24.

[0038] The spraying device 3 includes a pneumatic conveying component 31, a spraying component 32, and a return air collection component 33. The pneumatic conveying component 31 includes a fan 311, an air box 312, a pneumatic conveying hose 313, and an air volume regulating valve 314. The fan 311 is connected to the air inlet of the air box 312. A plurality of pneumatic conveying hoses 313 are connected to the air outlet of the air box 312, and an air volume regulating valve 314 is arranged on each pneumatic conveying hose 313. The middle of each pneumatic conveying hose 313 is connected to a foamed ball blanking pipe 24.

[0039] The spraying assembly 32 is located inside the paving bin 14, and is erected above the slab conveyor belt 15 and below the discharge port of the fiber feeding bin 11. The spraying assembly 32 includes a spraying pipe 321, a plurality of foaming ball accelerating pipes 322, and a plurality of foaming ball nozzles 323. Each of the foaming ball accelerating pipes 322 is arranged inside the spraying pipe 321. The space formed between the inner wall and the outer wall of the spraying pipe 321 is a return air collection chamber 3211. One end of each of the foaming ball accelerating pipes 322 is respectively connected to a corresponding pneumatic conveying hose 313. Each of the foaming ball nozzles 323 penetrates through the spraying pipe 321. The inlet of each of the foaming ball nozzles 323 is connected to the corresponding foaming ball accelerating pipe 322, and the outlet of each of the foaming ball nozzles 323 extends to the outside of the spraying pipe 321. Threads (not shown in the figure) are provided on the inner wall and the outer wall at the through hole of the spraying pipe 321 where the foaming ball nozzle 323 penetrates. Two sets of screw teeth 3231 corresponding to the threads are provided on each of the foaming ball nozzles 323, and the spraying pipe 321 and each of the foaming ball nozzles 323 are connected by the threads and the screw teeth 3231. The inlet of each of the foaming ball nozzles 323 and the corresponding foaming ball accelerating pipe 322 are respectively connected by a universal ball joint 3232.

[0040] And a plurality of air vent holes 3233 are distributed on the pipe wall of each of the foaming ball nozzles 323. The diameter of the air vent holes 3 is smaller than the smallest diameter of the foaming balls, usually 1 mm - 1.5 mm. Bearings 324 are sleeved at both ends of the spraying pipe 321, and the two bearings 324 are both fixed on the trolley 325. A swing device 326 is further connected to the end of the spraying pipe 321. The swing device 326 cooperates with the bearings 324 to control the spraying pipe 321 to rotate back and forth along the bearings 324 at both ends.

[0041] The setting position of the long bundle teeth 162 on the leveling roller 16 corresponds to each of the foaming ball nozzles 323.

[0042] The return air collection assembly 33 includes a return air collection pipe 331, a return air main pipe 332, a return air valve 333, an air inlet pipe 334, and an air inlet valve 335. The return air collection pipe 331 is communicated with the return air collection chamber 3211, and the other end of the return air collection pipe 331 is connected to the return air main pipe 332. The return air main pipe 332 is connected to the middle of the air inlet pipe 334. The outlet end of the air inlet pipe 334 is connected to the fan 311. The return air valve 333 is arranged on the return air main pipe 332, and the air inlet valve 335 is arranged at the inlet end of the air inlet pipe 334.

[0043] A vibrator (not shown in the figure) is further arranged outside the distribution bin 23. With the vibration of the vibrator, the foaming balls in the distribution bin 23 can be driven to vibrate, so as to avoid the foaming balls in the distribution bin from bridging and uneven distribution.

[0044] The material distribution plate 231 includes a distribution plate 2311 and an adjusting rod 2312 penetrating through the distribution plate 2311 in parallel. Both ends of the adjusting rod 2312 are rotatably arranged on the side wall of the distribution bin 23. By rotating the adjusting rod 2312, the distribution plate 2311 is rotated to control the fabric situation on the front and back sides and prevent uneven fabric distribution.

[0045] One end of the distribution plate 232 is provided with a first handle 2322, and one end of the current-limiting plate 234 is provided with a second handle 2342. Two installation grooves (not shown in the figure) are arranged in the distribution bin 23. One end of each installation groove penetrates the side wall of the distribution bin 23. The distribution plate 232 and the current-limiting plate 234 are detachably arranged in the installation grooves, and the first handle 2322 and the second handle 2342 extend outside the side wall of the distribution bin 23. The first handle 2322 and the second handle 2342 are used for the installation, replacement, and use of the distribution plate 232 and the current-limiting plate 234, that is, the distribution plate 232 and the current-limiting plate 234 with different diameters of through holes are replaced according to the actual situation.

[0046] Each metering bin 233 includes a cylindrical upper part and a conical lower part arranged up and down, and the inlet diameter of the metering bin 233 is larger than the outlet diameter of the metering bin. Each metering bin 233 is used for receiving and storing foaming balls.

[0047] Chamfers are arranged on the upper and lower edges of the first through hole 2321 and the upper edge of the second through hole 2341 to facilitate the smooth entry of foaming balls. The diameter of the first through hole 2321 is 3-5 mm, and the diameter of the second through hole 2341 is 3-4 mm.

[0048] The maximum angle that the spraying pipe 321 can rotate back and forth along the bearings 324 at both ends is 15° (that is, the maximum angle that can be rotated back and forth is 15°). The angle between each foaming ball nozzle 323 and the perpendicular line L of the spraying pipe 321 is -110° to +110° (that is, taking the lowest point of the perpendicular line L as 0°, counterclockwise is the positive angle, and clockwise is the negative angle). The lengths of the foaming ball nozzles 323 increase in sequence from bottom to top along the spraying pipe 321. That is, according to the positions of the foaming balls in the dry fiberboard blank designed according to actual production requirements, the angle that the spraying pipe 321 can rotate back and forth along the bearings 324 at both ends, the angle between each foaming ball nozzle 323 and the perpendicular line of the spraying pipe 321, and the lengths of the foaming ball nozzles 323 are adjusted.

[0049] A fiber shunt cover 327 is arranged above the spraying pipe 321 to shunt the dry fibers falling above the spraying pipe 321 to both sides of the spraying pipe 321.

[0050] In the present invention, the number of "multiple" is more than three, and the number of the first through hole 2321, the metering bin 233, the second through hole 2341, the blanking pipe 24, the pneumatic conveying hose 313, the foaming ball accelerating pipe 322, the foaming ball nozzle 323 and the long bundle teeth 162 corresponds to each other.

[0051] The working process of the present invention is as follows:

[0052] 1. Startup preparation: The dry fiberboard blank conveyor belt 15 runs, the paving rake 17, the discharge conveyor belt 12, and the fiber dispersion rollers 13 (multiple) wait for startup, and the dry fiber inlet of the fiber blanking bin 11 starts to feed materials (i.e., fibers, and the fibers used in production are dry fibers containing flame retardants).

[0053] The trolley 325 below the spraying pipe 321 runs, and the spraying pipe 321 with multiple foaming ball nozzles is placed below the discharge port of the paving bin 14 to prepare for spraying foaming ball particles.

[0054] The raw material of the foaming ball particles (the foaming ball particles are post-foaming flame-retardant polystyrene particles) is poured into the foaming ball bin 21, the air volume regulating valves 314 of the pneumatic conveying hoses 313 are opened, the return air valve 333 and the inlet air valve 335 of the return air collection assembly 33 are opened, the fan 311 is started to establish the return air working state; the distribution plate 231 is adjusted to select the distribution plate 232 and the current-limiting plate 234 with a suitable through-hole diameter. The vibrator is turned on, and the bottom edge of the discharge port of the screw discharger 22 is slidably and hermetically connected to the feed port of the distribution bin 23. The trolley 325 moves slowly left and right, and the swing device 326 works, so that the spraying pipe 321 rotates slowly in a circumferential direction before and after in the bearing 324, and the maximum angle is 15° of forward and backward rotation. The leveling roller 16 device starts to run.

[0055] 2. Startup: The paving rake 17, the discharge conveyor belt 12, and the fiber dispersion rollers 13 start to run, the dry fiber inlet of the fiber blanking bin 11 continues to feed materials, and the discharge port of the fiber blanking bin 11 continuously discharges materials. The screw discharger 22 runs, and the foaming ball raw materials fall from the discharge port of the screw discharger 22, enter the distribution bin 23 of the flame-retardant foaming balls, are adjusted and distributed by the distribution plate 231, then fall to the distribution plate 232, are evenly distributed to the multiple metering bins 233 below through screening by the distribution plate 232, and then are limited by the current-limiting plate 234 below, and the foaming balls fall into the blanking pipe 24. Under the mixing of the suction air of the return air collection assembly 33 and the pressurized air blown by the air box 312, the foaming balls are accelerated in the pneumatic conveying hose 313 and the foaming ball accelerating pipe 322, and finally are blown out from the outlet of the foaming ball nozzle 323.

[0056] The fiber diversion cover 327 above the spraying pipe 321 divides the continuous dry fiber blanking at the discharge port of the fiber blanking bin 11 into two parts of fibers. The fibers at the right outlet are the lower surface paving fibers for conventional paving; the fibers at the left outlet are the upper surface paving fibers for conventional paving. The flame-retardant foaming balls are sprayed onto the dry fiber slab blank in a large area at the angle where the foaming ball nozzle 323 is located, and finally appear as Figure 10 shown (the depths of the foaming balls 100 in the dry fiber slab blank 200 are different and are arranged in a continuous V shape). The distance h2 from the bottom foaming ball 100 to the bottom in the dry fiber slab blank 200 is greater than or equal to 20 mm. The distance h1 from the top foaming ball 100 to the highest point of the dry fiber slab blank 200 to the upper edge of the top of the dry fiber slab blank 200 is greater than or equal to 70 mm.

[0057] The foaming ball 100 is a post-foaming flame-retardant polystyrene particle ball and is foamed under high temperature and high pressure in a hot press. The leveling roller 16 is used to rake and remove the excess dry fibers on the slab on the slab conveyor belt 15, and the long-beam teeth 162 correspond to the laying device of the flame-retardant foaming ball 100, and are used to rake and remove the excess wood fibers above the position of the foaming ball 100 to form a groove 201, as Figure 10 shown. The depth h3 of the groove 201 is 40 - 60 mm, so that the fiber paving amount of the flame-retardant foaming ball particles in the vertical direction is less than that on both sides, and the pressure is less. When foaming in the press, it is guided to foam mainly in the vertical direction. When the flame-retardant foaming ball particles foam and expand, the groove 201 can be filled, as Figure 11 shown.

[0058] The leveling roller 16 is arranged to move left and right (not shown in the figure). The left and right moving distance is equal to the left and right moving distance of the foaming ball nozzle 323, and there is a fixed time lag of t = distance from the spraying pipe to the leveling roller / speed of the slab conveyor belt.

[0059] Due to the slow left and right movement of the trolley 325, the swing device 326 works, so that the spraying pipe 321 with multiple foaming ball nozzles 323 slowly swings back and forth at an angle of 0 - 15° in the bearing 324. At the same time, the size of the wind force is adjusted, so that the flame-retardant foaming balls 100 can be continuously ejected from each foaming ball nozzle 323, and are continuously ejected from each foaming ball nozzle 323 at different angles, different wind pressures and different positions and enter the dry fiber slab blank 200. The return air collection chamber 3211 collects the excess gas ejected from the vent holes 3233 of each foaming ball nozzle 323, passes through the return air collection pipe 331, passes through the return air main pipe 332 and the return air valve 333 and enters the fan 311.

[0060] The paving slab blank with post-foaming particles is transported to the subsequent pre-pressing, hot-pressing, and rough board treatment steps for production and treatment.

[0061] Shutdown: The screw discharging device 22 stops, ceasing material discharge. After the metering bin 233 finishes discharging, the fiber discharging bin 11 stops discharging. When the foaming ball nozzles 323 are no longer spraying, the fan 311 is turned off. Next, the oscillator 326 is closed, halting the system, and the dampers are closed. When the dry fiber mat conveyor belt 15 is clear of material, the trolley 325 moves, removing the spray pipe 321 containing the multiple foaming ball nozzles 323 from the laying bin 14. All systems are then shut down.

[0062] The advantages of the present invention are as follows:

[0063] 1. The flame-retardant foam ball spraying device of the present invention can control the foam balls to be sprayed to various cross-sectional positions of the fiberboard cross-sectional layer, thereby reducing the density of the board. It can also realize continuous spraying of the foam balls in the front, back, and bottom angles, flat shooting, parabolic shooting, left and right moving sweeping, free fall, and downward semicircular manners. The positions of the foam particles in the cross-section of the board are not in a straight line, which enhances the side nail holding force of the board and makes the board less prone to deformation. In addition, the board will not have large-area irregular pits, which will not affect the subsequent decoration and appearance of the board.

[0064] 2. The lightweight flame-retardant fiberboard produced using the present invention, under the same production process conditions, has a uniform fiber layer density, is not easily deformed, and can meet physical and mechanical performance indicators such as the side nail holding strength of the board. The lightweight flame retardancy meets the requirements of Class B and Class C flame-retardant boards specified in the national standard GB8624-2006 "Classification of Combustion Performance of Building Materials and Products." That is, the performance requirements of the lightweight fiberboard industry standard for use in a dry state at a density of 450 to 490 kilograms per cubic meter, and also meets the national requirements for Class C flame-retardant fireproof board.

[0065] Although the specific implementation modes of the present invention are described above, those skilled in the art should understand that the specific implementation modes described are only illustrative and are not intended to limit the scope of the present invention. Equivalent modifications and changes made by those skilled in the art in accordance with the spirit of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A flame-retardant foaming ball shunt spraying system for fiberboard, characterized in that: It includes a shunt device and a spraying device. The shunt device includes a foaming ball silo, a screw feeder, a distribution bin, and a foaming ball blanking pipe. A screw feeder is arranged at the outlet of the foaming ball silo, and the outlet of the screw feeder is arranged above the distribution bin. The foaming ball blanking pipe is connected to the lower part of the distribution bin; In the distribution bin, a material dividing plate, a distribution plate, a plurality of metering bins, and a flow limiting plate are sequentially arranged from top to bottom. The distribution plate is distributed with first through holes, and the inlets of the metering bins are communicated with the corresponding first through holes; the flow limiting plate is distributed with second through holes, and the outlets of the metering bins are communicated with the corresponding second through holes; the lower ends of the second through holes are connected to the corresponding foaming ball blanking pipes; The spraying device includes a pneumatic conveying component, a spraying component, and a return air collection component. The pneumatic conveying component includes a fan, an air box, a pneumatic conveying hose, and an air volume regulating valve. The fan is connected to the air inlet of the air box, and a plurality of pneumatic conveying hoses are connected to the air outlet of the air box. An air volume regulating valve is arranged on each pneumatic conveying hose; a foaming ball blanking pipe is connected to the middle of each pneumatic conveying hose; The spraying component includes a spraying pipe, a plurality of foaming ball accelerating pipes, and a plurality of foaming ball nozzles. Each foaming ball accelerating pipe is arranged inside the spraying pipe, and the space formed between the inner wall and the outer wall of the spraying pipe is a return air collection chamber; one end of each foaming ball accelerating pipe is respectively connected to the corresponding pneumatic conveying hose, each foaming ball nozzle penetrates through the spraying pipe, the inlet of each foaming ball nozzle is connected to the corresponding foaming ball accelerating pipe, and the outlet of each foaming ball nozzle extends to the outside of the spraying pipe; and a plurality of air vent holes are distributed on the pipe wall of each foaming ball nozzle, and the diameter of the air vent holes is smaller than the smallest diameter of the foaming balls; bearings are sleeved at both ends of the spraying pipe, and the two bearings are both fixed on the trolley; The maximum angle at which the spraying pipe can rotate back and forth along the bearings at both ends is 15°; The included angle between each foaming ball nozzle and the vertical line of the spraying pipe is from -110° to +110°; The lengths of the foaming ball nozzles increase sequentially from bottom to top along the spraying pipe; The return air collection component includes a return air collection pipe, a return air main pipe, a return air valve, an air inlet pipe, and an air inlet valve. The return air collection pipe is communicated with the return air collection chamber, and the other end of the return air collection pipe is connected to the return air main pipe. The return air main pipe is connected to the middle of the air inlet pipe, the outlet end of the air inlet pipe is connected to the fan, the return air valve is arranged on the return air main pipe, and the air inlet valve is arranged at the inlet end of the air inlet pipe.

2. The flame-retardant foaming ball shunt spraying system for a fiberboard according to claim 1, wherein: A vibrator is also arranged outside the distribution bin.

3. A flame-retardant foaming ball shunt spraying system for a fiberboard according to claim 1, characterized in that: One end of the distribution plate is provided with a first handle, and one end of the flow limiting plate is provided with a second handle; two installation grooves are arranged in the distribution bin, and one end of each installation groove penetrates through the side wall of the distribution bin. The distribution plate and the flow limiting plate are detachably arranged in the installation grooves, and the first handle and the second handle extend outside the side wall of the distribution bin.

4. A flame-retardant foaming ball shunt spraying system for a fiberboard according to claim 1, characterized in that: Each metering bin includes a cylindrical upper part and a conical lower part arranged up and down, and the inlet diameter of the metering bin is larger than the outlet diameter of the metering bin.

5. A flame-retardant foaming ball shunt spraying system for a fiberboard according to claim 1, characterized in that: Chamfers are provided at the upper and lower edges of the first through hole and the upper edge of the second through hole.

6. The flame-retardant foaming ball shunt spraying system for a fiberboard according to claim 1, wherein: The diameter of the first through hole is 3 - 5 mm, and the diameter of the second through hole is 3 - 4 mm.

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