Device and method for preparing fly ash-based foamed ceramic thermal insulation material

Abstract

The invention discloses a device and method for preparing a fly ash-based foamed ceramic thermal insulation material, and relates to the technical field of foamed ceramic molding, the device comprises a roller conveyor, a mold, and a gradient material distribution assembly and a compaction assembly which are sequentially arranged along the conveying direction; the gradient material distribution assembly is arranged on the upstream portion of the roller type conveyor and comprises a material bin with two independent cavities, a reciprocating driving mechanism and a discharging control mechanism. The compaction assembly comprises a pressure oil cylinder and a jacking oil cylinder which are coaxially and vertically arranged, the pressure oil cylinder is connected with a pressing template through an angle control mechanism, the jacking oil cylinder is connected with a supporting frame through an angle control mechanism, and the pressing template is always parallel to the supporting frame; during pressing, the angle control mechanism can change the inclination angle of the pressing template and the support frame. According to the device, vertical pressing is carried out, inclined pressing is carried out by changing the angle of the pressing template, the arch bridge effect among particles is effectively destroyed, and the density uniformity of a green body is improved.

Description

Technical Field

[0001] This invention relates to the field of foamed ceramic molding technology, and in particular to an apparatus and method for preparing fly ash-based foamed ceramic insulation materials. Background Technology

[0002] Fly ash is a major solid waste generated by coal-fired power plants. Its main chemical components are SiO2 and Al2O3, which are similar to those of ceramic raw materials, making it a potential material for producing foamed ceramics. Fly ash-based foamed ceramics are lightweight porous materials made from fly ash as the main raw material, with the addition of foaming agents, fluxes, and other auxiliary materials, through processes such as molding and sintering. They feature low thermal conductivity, high compressive strength, and good fire resistance, and can be widely used in building insulation, industrial insulation, and other fields.

[0003] However, fly ash raw materials have problems such as irregular particle morphology, wide particle size distribution, and large fluctuations in composition, which lead to the following special challenges in the preparation of foamed ceramics. In the existing dry preparation process of foamed ceramics, vertical unidirectional pressurization technology is generally used, which uses a hydraulic press to vertically press the powder in the mold. However, for thick green bodies, due to the frictional resistance between powder particles, the pressure will be significantly attenuated when it is transmitted to the center area of ​​the green body, resulting in obvious density differences between the edge and the center areas. In addition, the powder particles are prone to forming an arching effect, which further causes uneven distribution of pores inside the green body and affects the foaming uniformity of the final product. To compensate for the pressure loss, it is necessary to extend the holding time, which leads to reduced production efficiency and increased energy consumption. Summary of the Invention

[0004] The purpose of this invention is to solve the problem of significant density difference between the edge and center regions of the blank during dry pressing in the prior art, and to propose a fly ash-based foamed ceramic insulation material preparation device and method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A device for preparing fly ash-based foamed ceramic insulation material includes a roller conveyor, a mold, a gradient material distribution assembly and a compaction assembly arranged sequentially along the conveying direction;

[0007] A gradient fabric assembly, positioned upstream of the roller conveyor, includes:

[0008] A silo with two independent chambers, each storing raw materials with different foaming agent contents;

[0009] A reciprocating drive mechanism drives the hopper to move laterally;

[0010] The discharge control mechanism alternately opens the discharge ports of two independent chambers.

[0011] The compaction assembly includes a pressure cylinder and a lifting cylinder arranged coaxially and vertically. The pressure cylinder is connected to the pressing template through an angle control mechanism, and the lifting cylinder is connected to the support frame through an angle control mechanism. The pressing template and the support frame always remain parallel.

[0012] The mold has a frame plate and two side plates hinged to the frame plate. During pressing, the angle of the pressing plate and the support frame is changed by the angle control mechanism, so that the mold forms an inclined parallelogram structure, which decomposes the vertical pressure into a shear component.

[0013] Preferably, a partition plate is fixedly installed inside the hopper, and the two independent chambers are located on both sides of the partition plate. The partition plate and the inner wall of the hopper have a discharge gap for the chambers to discharge material. The bottom cross section of the hopper is inverted trapezoidal, forming a long strip-shaped material outlet. The length of the material outlet is adapted to the width of the mold.

[0014] Preferably, the discharge control mechanism is disposed inside the fabric inlet and includes:

[0015] Two baffles are rotatably mounted at the bottom of the partition plate to shield the discharge gaps of different chambers;

[0016] The torsion structure includes a mounting cover fixedly installed on the outer wall of the hopper. The baffle plate's rotating shaft extends out of the hopper and is provided with a disc. A spring is provided between the disc and the mounting cover. The springs corresponding to the two baffle plates have opposite spiral directions, so that the baffle plates close the discharge gap under normal conditions.

[0017] The pressure rod has one end rotatably connected to the rotating shaft of the baffle plate and the other end is equipped with a roller. The disc has a limit groove on the side near the pressure rod. The pressure rod is equipped with a limit post extending into the limit groove. When the pressure rod is in a natural hanging state, the roller is flush with the top surface of the frame plate.

[0018] The guide plate is set on the top surface of the frame plate, with beveled ends.

[0019] Preferably, the top surface of the guide plate has continuous corrugated grooves.

[0020] Preferably, the reciprocating drive mechanism has two guide rods, the side wall of the hopper is provided with a mounting block that slides with the guide rods, and also includes a control cylinder, which is arranged parallel to the guide rods and fixed to the side wall of the hopper.

[0021] Preferably, the angle control mechanism includes a connecting block, the connecting block having an arc-shaped groove and a mounting cavity, an arc-shaped ring slidingly disposed in the arc-shaped groove, the outer surface of the arc-shaped ring having incomplete worm gear teeth, a worm being rotatably disposed in the mounting cavity, the worm meshing with the incomplete worm gear teeth, and a control motor for driving the worm to rotate being fixedly installed outside the connecting block.

[0022] Preferably, both sides of the pressing template are rotatably provided with U-shaped snap-fit ​​plates, and the top surface of the side plate is provided with a snap-fit ​​slot adapted to the snap-fit ​​plates. The snap-fit ​​plates are obliquely connected to the upper surface of the pressing template by telescopic spring rods. Under non-external force, the snap-fit ​​plates are in a vertical state.

[0023] Preferably, the arc-shaped ring located above is fixedly connected to the top surface of the pressure plate, and the center of the arc-shaped ring is on the same plane as the hinge axis of the pressure plate and the snap-fit ​​plate;

[0024] The lower arc-shaped ring is fixedly connected to the bottom surface of the support frame, and the center of the arc-shaped ring and the hinge axis of the side plate and the frame plate are located in the same plane.

[0025] Preferably, the side plate pivot extends out of the frame plate and is fitted with a cylinder. The cylinder has a radially formed insertion hole. A slider is slidably mounted on the frame plate. A rod is mounted on one end of the slider near the cylinder. A spring is provided between the slider and the frame plate. A through-hole wedge-shaped groove is formed on the slider. An opening extending to the starting position of the inclined side of the wedge-shaped groove is formed at the bottom of the frame plate. A positioning rod is provided on the support frame corresponding to the opening.

[0026] A method for producing foamed ceramics from fly ash includes the following steps:

[0027] S1, Gradient Fabric Stage

[0028] The mold moves with the roller conveyor to below the gradient fabric assembly;

[0029] Start the reciprocating drive mechanism to move the hopper laterally:

[0030] As the process moves, the outlet of the independent chamber containing the low foaming agent content raw material is opened, and the lower layer of raw material is laid in the mold;

[0031] During the return stroke, the outlet of the independent chamber containing the high foaming agent content raw material is opened, and the intermediate layer of raw material is laid in the mold.

[0032] The mold continues to move forward, and through relative movement with the hopper, it completes the laying of the upper layer of low foaming agent raw material, forming a three-layer gradient fabric structure;

[0033] S2, Dynamic Suppression Stage

[0034] The mold moves to the bottom of the compaction component, and the pressure cylinder and lifting cylinder are activated;

[0035] Vertical initial pressure: Press the template vertically downwards to 10-20MPa;

[0036] First tilting and pressing: Adjust the tilt angle between the pressing template and the support frame to 5°~25° using the angle control mechanism, and apply pressure to 30-50MPa;

[0037] Second tilting press: Adjust the tilt angle between the pressure template and the support frame to -5° to -25°, and repeat the pressurization;

[0038] Vertical pressure holding: Return to vertical position and hold pressure for 10-30 seconds;

[0039] Output the mold to complete the pressing process.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] 1. By designing the mold side plate and bottom plate as hinged, and with the tiltable pressing plate and support frame, the traditional vertical pressure generates a shear component, so that the ceramic raw materials such as fly ash particles are not only subjected to vertical compression during the pressing process, but also generate relative sliding through tilting pressing, which effectively destroys the arch bridge effect between particles and improves the density uniformity of the green body; the parallelogram deformation of the mold is reversible and can be automatically reset after pressing, without affecting continuous production.

[0042] 2. The design of the pressing sequence of first vertical pre-pressing and then bidirectional tilting ensures that the initial vertical pressure establishes basic density, the bidirectional shear force eliminates the anisotropy caused by unidirectional pressing, and finally the vertical pressure holding stabilizes the billet structure.

[0043] 3. Two independent silos store fly ash mixtures with different foaming agent contents respectively; a precise discharge control mechanism ensures no cross-contamination of raw materials in each layer; a reciprocating motion mechanism enables efficient operation of one layer of material in one stroke, and through the material distribution path of "outward stroke - return stroke - outward stroke", it naturally forms a layer with low foaming agent content at the top and bottom, a middle layer with high foaming agent content, and a middle high foaming agent layer: ensuring sufficient foaming in the temperature lag stage, and the top low foaming agent layer maintaining an open-cell structure until the later stage of sintering, ensuring that the product quality will not decrease under the condition of accelerated production cycle. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the overall structure of the fly ash-based foamed ceramic insulation material preparation device proposed in this invention. Figure 1 ;

[0045] Figure 2 This is a schematic diagram of the overall structure of the fly ash-based foamed ceramic insulation material preparation device proposed in this invention. Figure 2 ;

[0046] Figure 3 This is a schematic diagram of the silo structure in the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0047] Figure 4 This is a cross-sectional view of the silo portion of the fly ash-based foamed ceramic insulation material preparation device proposed in this invention.

[0048] Figure 5 This is a schematic diagram of the structure of the baffle plate in the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0049] Figure 6 for Figure 5 A magnified structural diagram of part A in the middle;

[0050] Figure 7 This is a schematic diagram of the stepped fabric structure in this invention;

[0051] Figure 8 This is a schematic diagram of the compaction component in a fly ash-based foamed ceramic insulation material preparation device proposed in this invention.

[0052] Figure 9 This is a schematic diagram of the structure of the pressure template in the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0053] Figure 10 This is a schematic diagram of the support frame in the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0054] Figure 11 This is an exploded structural diagram of the angle control mechanism in a fly ash-based foamed ceramic insulation material preparation device proposed in this invention.

[0055] Figure 12 This is a schematic diagram of the mold structure in the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0056] Figure 13 This is a schematic diagram of the forward compaction structure of a fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0057] Figure 14 This is a schematic diagram of the inclined compaction structure of the fly ash-based foamed ceramic insulation material preparation device proposed in this invention;

[0058] Figure 15 This is a schematic diagram of the side plate unlocked state of the device for preparing fly ash-based foamed ceramic insulation material according to the present invention.

[0059] In the diagram: 1. Roller conveyor; 2. Gradient material distribution assembly; 21. Hopper; 211. Material distribution port; 212. Divider plate; 22. Mounting block; 23. Discharge control mechanism; 231. Baffle plate; 232. Mounting cover; 233. Disc; 234. Spring; 235. Pressing rod; 236. Roller; 237. Limiting groove; 238. Limiting post; 239. Guide plate; 2391. Corrugated groove; 24. Reciprocating drive mechanism; 241. Guide rod; 242. Control cylinder; 3. Compaction assembly; 31. Pressure oil. 32. Lifting cylinder; 33. Pressing template; 331. Clip plate; 332. Telescopic spring rod; 34. Support frame; 341. Positioning rod; 35. Angle control mechanism; 351. Connecting block; 352. Arc groove; 353. Mounting cavity; 354. Arc ring; 355. Incomplete worm gear tooth; 356. Worm; 357. Control motor; 4. Mold; 41. Side plate; 411. Bayonet; 412. Cylindrical; 413. Insertion hole; 42. Frame plate; 421. Slider; 422. Insert rod; 423. Wedge groove. Detailed Implementation

[0060] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0061] Reference Figure 1-15 A device for preparing fly ash-based foamed ceramic insulation material includes a roller conveyor 1, a mold 4, a gradient material distribution assembly 2 and a compaction assembly 3 arranged sequentially along the conveying direction.

[0062] In the preparation of foamed ceramics, especially for thicker blanks, the ceramic raw materials (powder) are laid in mold 4 and fired together in a roller kiln. The heating rate in the kiln depends on the heating rate of mold 4. Since mold 4 is a metal mold, it is heated first. Air and the ceramic raw materials themselves have poor thermal conductivity. Therefore, the ceramic raw materials on the side walls and bottom of mold 4 are often heated first, followed by the top layer, and the middle layer is heated last. As a result, the heating rate of the middle layer is often the slowest. The oxidation and degassing of the middle layer is often not effective. By increasing the foaming agent content of the middle layer, the density of the foaming units is increased, and the foaming time is shortened. By reducing the foaming agent content of the top layer, the melting and sealing speed of the top layer is delayed, and the foaming and sintering speed is also delayed. After the middle and bottom ceramic raw materials have been heated and degassed, the top layer melts, seals, and foams again, thereby improving the overall quality of the foamed ceramics.

[0063] Specifically, in order to support the production of foamed ceramics and improve production continuity, a gradient material distribution component 2 is set up to achieve automated multi-layer gradient material distribution.

[0064] Reference Figure 2-4The gradient material distribution assembly 2 is located upstream of the roller conveyor 1 and includes a hopper 21 with two independent chambers, a reciprocating drive mechanism 24, and a discharge control mechanism 23.

[0065] The two independent chambers store raw materials with different foaming agent contents. One independent chamber stores raw materials with high foaming agent content for the middle layer fabric of mold 4, and the other independent chamber stores raw materials with low foaming agent content for the upper and lower layers fabric of mold 4.

[0066] Reference Figure 2-4 The reciprocating drive mechanism 24 drives the hopper 21 to move laterally. The driving direction of the reciprocating drive mechanism 24 is parallel to the conveying direction of the roller conveyor 1, and the driving method is reciprocating drive. In conjunction with the discharge control mechanism 23, the two independent chambers are switched to discharge material during the process of progress and return.

[0067] The reciprocating drive mechanism 24 has two guide rods 241. The side wall of the hopper 21 is provided with mounting blocks 22 that slide with the guide rods 241. The two guide rods 241 are arranged in parallel. The guide rods 241 are fixed on the channel steel support. At least two mounting blocks 22 are installed on the same side of the hopper 21. The guide rods 241 pass through the mounting blocks 22. The guide rods 241 support and slide guide the hopper 21. The two mounting blocks 22 on the same side can ensure the stability of the hopper 21. The reciprocating drive mechanism 24 also includes a control cylinder 242. The control cylinder 242 is also installed on the channel steel support. The control cylinder 242 is arranged in parallel with the guide rods 241 and fixed to the side wall of the hopper 21. By extending and retracting the control cylinder 242, the hopper 21 is controlled to reciprocate along the axial direction of the guide rods 241.

[0068] Reference Figure 2-7 The discharge control mechanism 23 alternately opens the discharge ports of the two independent chambers. The discharge control mechanism 23, in conjunction with the movement of the hopper 21, achieves automatic control and adjustment. During each material feeding process, the hopper 21 performs one reciprocating stroke. The mold 4 first moves to a stop below the gradient material feeding assembly 2, then controls the hopper 21 to move from one end of the mold 4 to the other to complete the process. Initially, both independent chambers are closed. During the process, the independent chamber storing low foaming agent content opens, and the independent chamber storing high foaming agent content closes. As the hopper 21 moves, the raw material with low foaming agent content is fed into the mold 4 to complete the bottom layer feeding (e.g., ...). Figure 7 As shown in Figure a), during the return stroke, the independent chamber storing high foaming agent content opens, while the independent chamber storing low foaming agent content closes, allowing the high foaming agent content raw material to be placed into mold 4 to complete the middle layer fabrication (as shown in Figure a). Figure 7As shown in Figure b), at this time, the hopper 21 reaches the initial position, and the mold 4 is moved. The relative displacement between the mold 4 and the hopper 21 at this time is consistent with the relative displacement between the mold 4 and the hopper 21 during the process. Similarly, the independent chamber storing low foaming agent content is opened, and the independent chamber storing high foaming agent content is closed. As the mold 4 moves, the raw material with low foaming agent content is placed into the mold 4 to complete the upper layer of material distribution (e.g., ...). Figure 7 As shown in c), this allows for the automated implementation of multi-layer gradient fabric.

[0069] A partition plate 212 is fixedly installed inside the hopper 21. Two independent chambers are located on both sides of the partition plate 212. The partition plate 212 and the inner wall of the hopper 21 have a discharge gap for the chambers to discharge material. The bottom cross section of the hopper 21 is inverted trapezoidal, forming a long strip of material feeding port 211. The length of the material feeding port 211 is adapted to the width of the mold 4. When the mold 4 and the hopper 21 are relatively displaced, the linear raw material output from the long strip of material feeding port 211 can fill the cross section of the mold 4. Above the discharge gap, there are also uniform material distribution plates equidistantly arranged along the length of the material feeding port 211 to ensure uniform material discharge.

[0070] Reference Figure 2-7 The discharge control mechanism 23 is located inside the material outlet 211 and includes a torsion structure, a pressure rod 235, a guide plate 239, and two baffle plates 231. The two baffle plates 231 are rotatably mounted on the bottom end of the partition plate 212 to cover the discharge gaps of different chambers. Under the action of the torsion structure, the baffle plates 231 are kept in the state of blocking the discharge gaps. When the pressure rod 235 cooperates with the guide plate 239, a circumferential force is applied to the rotating shaft of the baffle plates 231, causing the baffle plates 231 to deflect and thus expose the discharge gaps.

[0071] The torsion structure includes a mounting cover 232 fixedly installed on the outer wall of the hopper 21. The rotating shaft of the baffle plate 231 extends from the discharge hopper 21 and is provided with a disc 233. The disc 233 is coaxially arranged with the mounting cover 232. A spring 234 is provided between the disc 233 and the mounting cover 232. The elastic force of the spring 234 acts on the rotating shaft of the baffle plate 231, driving the baffle plate 231 to block the discharge gap. The spiral directions of the spring 234 corresponding to the two baffle plates 231 are opposite, so the deflection directions of the two baffle plates 231 are also opposite, so that the two baffle plates 231 can seal the discharge gap of the two independent chambers under normal conditions.

[0072] Reference Figure 2-7One end of the pressure rod 235 is rotatably connected to the pivot of the baffle plate 231, and the other end is equipped with a roller 236. Under normal conditions, the pressure rod 235 hangs naturally under the influence of gravity, and the roller 236 is flush with the top surface of the frame plate 42. A limiting groove 237 is formed on the side of the disc 233 near the pressure rod 235. A limiting post 238 is provided on the pressure rod 235, extending into the limiting groove 237. The limiting groove 237 is arc-shaped. When the pressure rod 235 rotates, the limiting post 238 can move within the limiting groove 237. When the pressure rod 235 is in a vertical state... The limiting post 238 is at one extreme position of the limiting groove 237. Therefore, there are two situations when the limiting post 238 rotates in different directions. The first is a driven rotation, that is, the limiting post 238 directly pushes the end of the limiting groove 237, causing the baffle plate 231 to rotate. At this time, the baffle plate 231 will open accordingly. The second is an ineffective rotation, that is, the limiting post 238 moves along the limiting groove 237 to another extreme position. At this time, there is no effective force contact between the limiting post 238 and the limiting groove 237, and the rotation of the pressing rod 235 does not have any effect on the baffle plate 231.

[0073] Reference Figure 2-7 and Figure 12 The guide plate 239 is set on the top surface of the frame plate 42. During the movement of the hopper 21, the pressure rod 235 moves with the hopper 21 and contacts the guide plate 239. The two ends of the guide plate 239 are at bevels and contact the roller 236, which plays a guiding transition role, causing the pressure rod 235 to deflect. On the outward stroke, the pressure rod 235 corresponding to the baffle plate 231 used to block the discharge gap of low foaming agent content is driven to rotate, and the discharge gap is opened. On the return stroke, the pressure rod 235 corresponding to the baffle plate 231 used to block the discharge gap of low foaming agent content rotates ineffectively. Under the action of the torsion structure, the discharge gap is closed. The limiting grooves 237 corresponding to the two baffle plates 231 are set in opposite directions. Therefore, the two baffle plates 231 are in different states during the reciprocating stroke, realizing the automatic opening and closing of the two independent chambers.

[0074] The top surface of the guide plate 239 has a continuous corrugated groove 2391. When the pressure rod 235 is in the driving rotation state, the limit post 238 controls the baffle plate 231 to open. When the roller 236 moves in the corrugated groove 2391, the deflection angle of the pressure rod 235 changes continuously. Combined with the torsion structure, the baffle plate 231 will swing back and forth, thereby improving the smoothness of raw material discharge.

[0075] Reference Figure 8-15The compaction assembly 3 includes a pressure cylinder 31 and a lifting cylinder 32 arranged coaxially and vertically. The pressure cylinder 31 is installed at the top with its output end pointing downwards, while the lifting cylinder 32 is installed at the bottom with its output end pointing upwards. The pressure cylinder 31 is connected to the pressing platen 33 via an angle control mechanism 35, and the lifting cylinder 32 is connected to the support frame 34 via the angle control mechanism 35. The pressing platen 33 and the support frame 34 are always kept parallel. The two angle control mechanisms 35 operate synchronously to keep the pressing platen 33 and the support frame 34 in a parallel state. The support frame 34 can lift the mold 4, and work with the pressing platen 33 to press the raw material in the mold 4 into shape. For blanks with large thicknesses, during pressing, since the powder raw material does not flow like a liquid... Despite its excellent properties, the frictional resistance of the powder hinders pressure transmission. When the pressure reaches the center of the green body, it significantly attenuates, resulting in a noticeable density difference between the edge and center areas. The resistance between particles forms a stress arch, and the arch bridge effect between powder particles further causes uneven distribution of pores inside the green body, affecting the foaming uniformity of the final product. By using the angle control mechanism 35, the angles of the pressing template 33 and the support frame 34 can be changed, thereby compacting the raw materials in the mold 4 at different angles. This allows the ceramic raw materials, such as fly ash particles, to not only be vertically compressed during the pressing process but also to slide relatively during inclined pressing, effectively breaking the arch bridge effect between particles and improving the density uniformity of the green body.

[0076] The mold 4 has a frame plate 42 and two side plates 41 hinged to the frame plate 42. The frame plate 42 has a U-shaped structure, which is formed by integrally welding the bottom plate and long side of the mold 4. The side plates 41 are hinged to the frame plate 42. Therefore, when the pressing template 33 is pressing, the frame plate 42, the two side plates 41 and the pressing template 33 form a movable parallelogram structure. When pressing vertically, the mold 4 is in a horizontal state. The pressure cylinder 31 applies vertically downward pressure. The pressure is perpendicular to the mold 4 and acts on the raw material through the pressing template 33. The angle control mechanism 35 changes the inclination angle of the pressing template 33 and the support frame 34, so that the mold 4 forms an inclined parallelogram structure. At this time, the mold 4 is inclined, and the pressing template 33 also maintains the same inclination angle. However, the direction of the force applied by the pressure cylinder 31 remains unchanged, still applying force vertically downward. Therefore, the force applied by the pressure cylinder 31 is inclined and acts on the raw material with the pressing template 33, decomposing the vertical pressure into a shear component, effectively destroying the arching effect between particles and improving the density uniformity of the blank.

[0077] The part where the roller conveyor 1 overlaps with the support frame 34 is formed on the conveying surface by adjusting the length of the roller, allowing the support frame 34 to pass through. Under the control of the lifting cylinder 32, the support frame 34 can lift the mold 4 on the roller conveyor 1 by rising and falling. When the mold 4 moves to the position of the compaction component 3 via the roller conveyor 1, the lifting cylinder 32 rises, lifting the mold 4 as a whole off the surface of the roller conveyor 1 for pressing. After the support frame 34 moves down to below the surface of the roller conveyor 1, the mold 4 can remain on the roller conveyor 1 and continue to be conveyed to the downstream equipment.

[0078] Reference Figure 8-15 The angle control mechanism 35 includes a connecting block 351, which has an arc-shaped groove 352 and a mounting cavity 353. An arc-shaped ring 354 is slidably disposed in the arc-shaped groove 352, and the arc-shaped ring 354 is adapted to and tightly fitted with the arc of the arc-shaped groove 352. The outer surface of the arc-shaped ring 354 is provided with incomplete worm gear teeth 355. In order not to affect the sliding of the arc-shaped ring 354, a slot is provided on the outer surface of the arc-shaped ring 354, in which the incomplete worm gear teeth 355 are installed in the slot and do not extend beyond the slot. A worm 356 is rotatably disposed in the mounting cavity 353. 6 is meshed with the incomplete worm gear 355. A control motor 357 that drives the worm 356 to rotate is fixedly installed outside the connecting block 351. The control motor 357 drives the worm 356 to rotate. The rotation of the worm 356, in conjunction with the incomplete worm gear 355, drives the arc ring 354 to slide in the arc groove 352. The upper arc ring 354 is fixedly connected to the top surface of the pressure plate 33, and the lower arc ring 354 is fixedly connected to the bottom surface of the support frame 34. The angle control of the pressure plate 33 and the support frame 34 is achieved by the sliding of the arc ring 354.

[0079] To maintain the relative stability of the pressing plate 33 with the side plate 41 of the mold 4, U-shaped locking plates 331 are rotatably provided on both sides of the pressing plate 33. The top surface of the side plate 41 has a slot 411 that matches the locking plate 331. During pressing, the pressing plate 33 moves downward, and the locking plate 331 is first inserted into the slot 411. Because the locking plate 331 can rotate with the end of the pressing plate 33, when the pressing plate 33 changes angle and deforms to cooperate with the side plate 41, the locking plate 331 rotates with the pressing plate 33. The side plate 41 remains vertical, and the locking plate 331... Under the limit, the position of the side plate 41 can remain stable. During the pressing process of the pressing template 33, the snap-fit ​​plate 331 also moves down along the snap-fit ​​opening 411, thereby ensuring that as the thickness of the powder blank is compressed and changed, the parallelogram structure composed of the pressing template 33, the side plate 41 and the frame plate 42 changes synchronously. The snap-fit ​​plate 331 is connected to the upper surface of the pressing template 33 by the telescopic spring rod 332. Under the action of no external force, the snap-fit ​​plate 331 is in a vertical state, ensuring that the snap-fit ​​plate 331 on the pressing template 33 can be stably inserted into the snap-fit ​​opening 411 when the side plate 41 is snapped from the separated state.

[0080] It should be noted that, to ensure that all sides of the parallelogram structure composed of side plate 41, pressure plate 33, and frame plate 42 are equal, the bottom hinge of side plate 41 bends and extends inward toward the mold 4 until the distance between the hinge axes of side plate 41 and the distance between the hinge axes of snap-fit ​​plate 331 are equal. Furthermore, side plate 41, pressure plate 33, etc., all have a certain thickness. When the parallelogram structure deforms, this thickness will cause positional interference at the contact points of side plate 41, pressure plate 33, and frame plate 42 in a tightly fitted state. Therefore, the contact point between the bottom of side plate 41 and frame plate 42... The side plate 41 is machined into an arc shape with the pivot of the side plate 41 as the center. The two ends of the pressing plate 33 are machined into arc shapes with the pivot of the snap-fit ​​plate 331 as the center. The center of the arc ring 354 is on the same plane as the hinge axis of the pressing plate 33 and the snap-fit ​​plate 331. The center of the arc ring 354 is also on the same plane as the hinge axis of the side plate 41 and the frame plate 42. This ensures that the side plate 41, the pressing plate 33 and the frame plate 42 are in a close fit when the parallelogram structure is deformed. The irregular defects at the corners of the blank caused by the arc shape are dealt with in the subsequent grinding process after demolding.

[0081] The side plate 41 needs to maintain relative stability with the frame plate 42 during the material feeding and sintering processes. It only needs to deflect during the pressing process. Therefore, the rotating shaft of the side plate 41 extends out of the frame plate 42 and is fitted with a cylinder 412. An insertion hole 413 is radially formed on the cylinder 412. A slider 421 is slidably mounted on the frame plate 42. An insertion rod 422 is mounted on one end of the slider 421 near the cylinder 412. A spring is provided between the slider 421 and the frame plate 42. Under the action of the spring, the slider 421 is pushed towards the cylinder 412, and the insertion rod 422 is inserted into the insertion hole 413 to limit the rotating shaft of the side plate 41, preventing the side plate 41 from rotating during the material feeding process. A through-hole wedge-shaped groove 423 is formed on the slider 421. An opening extending to the starting position of the inclined side of the wedge-shaped groove 423 is formed at the bottom of the frame plate 42. A corresponding opening is formed on the support frame 34. The hole is equipped with a positioning rod 341. When the support frame 34 lifts the mold 4, the positioning rod 341 is inserted into the opening and acts on the inclined side of the wedge groove 423, causing the slider 421 to move away from the cylinder 412, so that the insert rod 422 is disengaged from the insertion hole 413. At this time, the side plate 41 can rotate freely, realizing the deformation of the mold 4 during the pressing process. It should be noted that during pressing, the pressure cylinder 31 needs to drive the pressing plate 33 to move down first, so that the snap plate 331 and the side plate 41 are stably inserted into the snap 411 before the lifting cylinder 32 can be driven to lift up and contact the limit of the side plate 41. Similarly, after pressing is completed, the lifting cylinder 32 needs to move down to make the positioning rod 341 disengage from the hole. After the insert rod 422 is inserted into the insertion hole 413 to limit the rotation of the side plate 41, the pressure cylinder 31 is driven to move up to separate the pressing plate 33 from the mold 4.

[0082] A method for producing foamed ceramics from fly ash includes the following steps:

[0083] S1, Gradient Fabric Stage

[0084] The mold 4 moves with the roller conveyor 1 to below the gradient fabric assembly 2;

[0085] The reciprocating drive mechanism 24 is activated, driving the hopper 21 to move laterally.

[0086] As the process moves, the outlet of the independent chamber containing the low foaming agent content raw material is opened, and the lower layer of raw material is laid in the mold 4;

[0087] During the return stroke, the outlet of the independent chamber containing the high foaming agent content raw material is opened, and the intermediate layer of raw material is laid in the mold 4.

[0088] The mold 4 continues to move forward, and through relative movement with the hopper 21, it completes the laying of the upper layer of low foaming agent raw material, forming a three-layer gradient fabric structure;

[0089] S2, Dynamic Suppression Stage

[0090] The mold 4 moves to the bottom of the compaction component 3, and the pressure cylinder 31 and the lifting cylinder 32 are activated;

[0091] Vertical initial pressure: Press the template 33 vertically downwards to 10-20MPa;

[0092] First tilting and pressing: Adjust the tilt angle between the pressing template 33 and the support frame 34 to 5°~25° using the angle control mechanism 35, and apply pressure to 30-50MPa;

[0093] Second tilting pressure: The tilt angle between the reverse adjustment template 33 and the support frame 34 is -5° to -25°, and pressure is applied repeatedly;

[0094] Vertical pressure holding: Return to vertical position and hold pressure for 10-30 seconds;

[0095] Output mold 4 to complete the pressing process.

Claims

1. A device for preparing fly ash-based foamed ceramic insulation material, comprising a roller conveyor (1), a mold (4), a gradient material distribution assembly (2) and a compaction assembly (3) arranged sequentially along the conveying direction, characterized in that: A gradient fabric assembly (2), located upstream of the roller conveyor (1), includes: A silo (21) with two independent chambers, each storing raw materials with different foaming agent contents; The reciprocating drive mechanism (24) drives the hopper (21) to move laterally; The discharge control mechanism (23) alternately opens the discharge ports of the two independent chambers; The compaction assembly (3) includes a pressure cylinder (31) and a lifting cylinder (32) arranged coaxially and vertically. The pressure cylinder (31) is connected to the pressing template (33) through an angle control mechanism (35), and the lifting cylinder (32) is connected to the support frame (34) through an angle control mechanism (35). The pressing template (33) and the support frame (34) always remain parallel. The mold (4) has a frame plate (42) and two side plates (41) hinged to the frame plate (42). During pressing, the angle of the pressing plate (33) and the support frame (34) is changed by the angle control mechanism (35) so that the mold (4) forms an inclined parallelogram structure, which decomposes the vertical pressure to generate a shear component.

2. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 1, characterized in that, A partition plate (212) is fixedly installed inside the hopper (21). The two independent chambers are located on both sides of the partition plate (212). The partition plate (212) and the inner wall of the hopper (21) have a discharge gap for the chambers to discharge material. The bottom cross section of the hopper (21) is inverted trapezoidal, forming a long strip of material outlet (211). The length of the material outlet (211) is adapted to the width of the mold (4).

3. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 2, characterized in that, The discharge control mechanism (23) is located inside the fabric outlet (211) and includes: Two baffles (231) are rotatably mounted at the bottom of the partition plate (212) to shield the discharge gaps of different chambers; The torsion structure includes a mounting cover (232) fixedly installed on the outer wall of the hopper (21). The rotating shaft of the baffle plate (231) extends out of the hopper (21) and is provided with a disc (233). A spring (234) is provided between the disc (233) and the mounting cover (232). The springs (234) corresponding to the two baffle plates (231) have opposite spiral directions, so that the baffle plate (231) closes the discharge gap under normal conditions. The pressure rod (235) is rotatably connected to the shaft of the baffle plate (231) at one end and a roller (236) is provided at the other end. The disc (233) has a limiting groove (237) on the side near the pressure rod (235). The pressure rod (235) is provided with a limiting post (238) extending into the limiting groove (237). When the pressure rod (235) is in a natural hanging state, the roller (236) is flush with the top surface of the frame plate (42). The guide plate (239) is set on the top surface of the frame plate (42) with beveled ends.

4. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 3, characterized in that, The top surface of the guide plate (239) has continuous corrugated grooves (2391).

5. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 1, characterized in that, The reciprocating drive mechanism (24) has two guide rods (241), and the side wall of the hopper (21) is provided with a mounting block (22) that slides with the guide rods (241). It also includes a control cylinder (242), which is arranged parallel to the guide rods (241) and fixed to the side wall of the hopper (21).

6. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 1, characterized in that, The angle control mechanism (35) includes a connecting block (351), an arc-shaped groove (352) and a mounting cavity (353) are provided in the connecting block (351), an arc-shaped ring (354) is slidably arranged in the arc-shaped groove (352), an incomplete worm gear tooth (355) is provided on the outer surface of the arc-shaped ring (354), a worm (356) is rotatably arranged in the mounting cavity (353), the worm (356) is meshed with the incomplete worm gear tooth (355), and a control motor (357) for driving the worm (356) to rotate is fixedly installed outside the connecting block (351).

7. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 1, characterized in that, Both sides of the pressing template (33) are rotatably provided with U-shaped snap-fit ​​plates (331). The top surface of the side plate (41) is provided with a snap-fit ​​slot (411) that is compatible with the snap-fit ​​plate (331). The snap-fit ​​plate (331) is connected to the upper surface of the pressing template (33) by a telescopic spring rod (332). Under non-external force, the snap-fit ​​plate (331) is in a vertical state.

8. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 7, characterized in that, The arc-shaped ring (354) located above is fixedly connected to the top surface of the pressure template (33), and the center of the arc-shaped ring (354) is on the same plane as the hinge axis of the pressure template (33) and the snap plate (331); The lower arc ring (354) is fixedly connected to the bottom surface of the support frame (34), and the center of the arc ring (354) is in the same plane as the hinge axis of the side plate (41) and the frame plate (42).

9. The apparatus for preparing fly ash-based foamed ceramic insulation material according to claim 1, characterized in that, The side plate (41) extends from the frame plate (42) and is fitted with a cylinder (412). The cylinder (412) has a radially arranged insertion hole (413). The frame plate (42) is slidably fitted with a slider (421). The slider (421) is fitted with an insertion rod (422) at one end near the cylinder (412). A spring is provided between the slider (421) and the frame plate (42). The slider (421) has a through-hole wedge-shaped groove (423). The bottom of the frame plate (42) has an opening extending to the starting position of the inclined side of the wedge-shaped groove (423). The support frame (34) is fitted with a positioning rod (341) corresponding to the opening.

10. A method for producing foamed ceramics from fly ash, using the fly ash-based foamed ceramic insulation material preparation apparatus as described in any one of claims 1-9, characterized in that... Includes the following steps: S1, Gradient Fabric Stage The mold (4) moves with the roller conveyor (1) to below the gradient fabric assembly (2); The reciprocating drive mechanism (24) is activated, driving the hopper (21) to move laterally: When the process moves, open the outlet of the independent chamber where the low foaming agent content raw material is located, and lay the lower layer of raw material in the mold (4); During the return stroke, the outlet of the independent chamber containing the high foaming agent content raw material is opened, and the intermediate layer of raw material is laid in the mold (4); The mold (4) continues to move forward, and completes the laying of the upper low foaming agent raw material through relative movement with the hopper (21), forming a three-layer gradient fabric structure; S2, Dynamic Suppression Stage The mold (4) moves to the bottom of the compaction component (3), and the pressure cylinder (31) and the lifting cylinder (32) are activated. Vertical initial pressure: Press the template (33) vertically downward to 10-20MPa; First tilting press: Adjust the tilt angle between the pressing template (33) and the support frame (34) to 5°~25° by using the angle control mechanism (35), and apply pressure to 30-50MPa; Second tilting pressure: The tilt angle between the reverse adjustment pressure template (33) and the support frame (34) is -5° to -25°, and pressure is applied repeatedly; Vertical pressure holding: Return to vertical position and hold pressure for 10-30 seconds; Output mold (4) to complete pressing.

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