A cross-linked polyolefin foaming device

Abstract

The present invention discloses a cross-linked polyolefin foaming device, comprising a vertical furnace for sheets to pass through for heated foaming, wherein the vertical furnace is provided with a heating system and a spreading roller mechanism arranged at two opposite side walls thereof; and the spreading roller mechanism comprises a first spreading roller and a second spreading roller; and one end of the first spreading roller and the second spreading roller is located inside the vertical furnace, and the other end is arranged outside the vertical furnace, and a sealing structure is provided at the junction of the above-mentioned spreading roller and the vertical furnace, and the sealing structure is arranged inside the side wall of the vertical furnace; the present invention realizes complete sealing at the junction of the spreading roller mechanism and the furnace wall by improving the vertical furnace and the spreading roller mechanism.

Description

Technical Field

[0001] The invention belongs to the technical field of foaming devices, and more specifically, relates to a cross-linked polyolefin foaming device. Background Art

[0002] Polyolefin plastics have a wide range of applications and have good physical, chemical and mechanical properties. They have good toughness, flexibility and cushioning properties, and have electrical insulation and heat insulation properties. They are widely used in packaging, chemical industry, construction and other fields. Polyolefin foam plastics are widely used and are also one of the earliest successfully produced foam plastics. Polyolefin foam materials are often foamed in a foaming furnace during the production process.

[0003] There are two main structures of existing foaming furnaces. One is a foaming furnace with a vertical furnace as the foaming section, and the other is a horizontal furnace set in front of the vertical furnace, which is composed of a horizontal furnace and a vertical furnace. In the second method, the entire foaming furnace is in the shape of a square. The horizontal furnace is mainly used to preheat the polyolefin mother sheet. After heating in different temperature intervals, the polyolefin mother sheet reaching the vertical furnace has a certain temperature, which is conducive to foaming and improves the foaming quality; the vertical furnace is the polyolefin mother sheet foaming section and is the main foaming completion station.

[0004] However, the horizontal furnace of the existing foaming furnace has the following problems:

[0005] First, when the polyolefin mother sheet is foamed in the vertical furnace, it will expand in thickness and width, causing the sheet to be "M" shaped. At this time, the mother sheet is in a semi-molten state. If it is not unfolded in time, the sheets will overlap and stick to each other, causing the product to be scrapped, or uneven heating, affecting the quality of the finished product. Therefore, it is necessary to unfold it in time through the unfolding roller mechanism. The foaming furnace is a long-term high-temperature environment, and the unfolding roller has horizontal movement in addition to rotation. The unfolding roller structure of the existing technology, on the one hand, does not have a complete and effective sealing or leak-proof device; on the other hand, the conventional polytetrafluoroethylene and other rubber and plastic materials are poor in high temperature resistance, easy to deform, and have poor sealing effect, which will cause the oil smoke generated during the foaming of the sheet to leak, causing indoor air pollution, serious equipment wear and corrosion, and heat loss in the vertical furnace.

[0006] Secondly, the transmission device adopts chain conveyor. The disadvantage of this method is that the chain is easy to be damaged, the efficiency is low, and iron filings are easily dropped after wear; on the other hand, the chain lock is easy to fall off and fall into the transmission equipment, causing damage to the equipment.

[0007] In addition, the heating devices in the existing vertical furnaces are mostly heating rods evenly distributed on the inner wall of the vertical furnace body, and the sheets in the vertical furnace are heated by the heat radiation generated by the heating rods. More advanced, the heating device in the vertical furnace adopts temperature zoning control, so that there is a reasonable temperature gradient distribution in the vertical furnace. However, in the existing technical solution, each temperature zone of the heating device is set inside the through vertical furnace hearth (there is no shielding between the temperature zones), so that the temperature zones affect each other, and the temperature of each temperature zone cannot be accurately controlled. At the same time, the internal space of the vertical furnace hearth is large, and the heat generated by the heating device cannot be well utilized, resulting in slow heating speed and low heating efficiency. Summary of the invention

[0008] In view of the above defects or improvement needs of the prior art, the present invention provides a cross-linked polyolefin foaming device, which realizes complete sealing at the junction of the roll spreading mechanism and the furnace wall by improving the vertical furnace and the roll spreading mechanism.

[0009] To achieve the above object, the present invention provides a cross-linked polyolefin foaming device, comprising a vertical furnace for a sheet to pass through for heating and foaming, wherein the vertical furnace has a spreading roller mechanism disposed on two opposite side walls thereof; and

[0010] The roll spreading mechanism comprises a first spreading roller and a second spreading roller; one end of the first spreading roller and the second spreading roller are located inside the vertical furnace, and the other end is arranged outside the vertical furnace, and a sealing structure is provided at the connection between the spreading roller and the vertical furnace.

[0011] Furthermore, the sealing structure is arranged inside the side wall of the vertical furnace, and the first unfolding roller passes through the sealing cover, the first sealing ring, the second sealing ring and the sealing ring in sequence.

[0012] Furthermore, the second unfolding roller passes through the fully sealed steel plate and the second sealing ring in sequence.

[0013] Furthermore, the first sealing ring and the second sealing ring are made of high temperature resistant mica plate and graphite.

[0014] Furthermore, corresponding rotary joints are provided at the outer ends of the first unrolling roller and the second unrolling roller, and each of the rotary joints includes a cold water inlet and a hot water outlet in different directions.

[0015] Furthermore, the foaming device also includes a horizontal furnace arranged above the vertical furnace, and a transmission mechanism is provided in the horizontal furnace, and the transmission mechanism includes an active roller, a passive roller, and a conveyor belt that connects the two to form a closed-loop conveying.

[0016] Furthermore, a passive roller bracket is provided at the bottom of the conveyor mesh belt, and U-shaped plates are provided on both lateral sides of the passive roller bracket, and telescopic devices are respectively fixed on the U-shaped plates.

[0017] Furthermore, the vertical furnace also has a heating system, which includes a transition mechanism, a pre-foaming mechanism and a foaming mechanism that are sequentially arranged from top to bottom to form an independent temperature section.

[0018] Furthermore, it also includes a feeding device, which includes an unwinding rack and a feeding traction roller for traction the foamed sheet on the unwinding rack to the transmission mechanism.

[0019] Furthermore, it also includes a discharging device for pulling the foamed sheet out of the vertical furnace, and the discharging device includes a calendering roller, a cooling roller, a correction roller, a winding frame and at least one pair of material collection and pulling rollers which are arranged in sequence at the exit of the vertical furnace.

[0020] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0021] (1) In the cross-linked polyolefin foaming device of the present invention, the unfolding roller enters the foaming furnace through the wall and adopts a fully enclosed sealing structure. On the one hand, the outer periphery is sealed by a fully enclosed steel plate. At the inlet and outlet positions where the unfolding roller mechanism enters the wall, a sealing ring, a sealing ring and a sealing cover are sequentially designed to realize a fully enclosed environment. This not only reduces oil smoke during foaming of the foamed semi-finished product and achieves a leak-proof effect, but also reduces the wear of the equipment.

[0022] (2) The cross-linked polyolefin foaming device of the present invention heats and foams the sheet material in sequence by arranging the first accommodating space, the second accommodating space, and the third accommodating space, which is conducive to more uniform foaming. The three accommodating spaces are relatively independent of each other, which can reduce the mutual influence between the various temperature zones, thereby improving the temperature control accuracy of each temperature zone. At the same time, the heat is concentrated in a smaller space relative to the furnace, which can improve the utilization rate of the heat and has the advantages of fast heating speed and high efficiency.

[0023] (3) The cross-linked polyolefin foaming device of the present invention adopts a transmission mechanism that uses a conveyor mesh belt in cooperation with an active roller and a passive roller for closed-loop transmission. The mesh belt is driven by the friction between the power roller and the mesh belt, replacing the transmission scheme of a transmission chain, gears, and guide rails. This solves the problem of iron filings and slag foam generated by the friction between the chain and the guide rail, and avoids oil pollution.

[0024] (4) The cross-linked polyolefin foaming device, the spreading roller mechanism and the sealing ring of the present invention are made of high temperature resistant mica plate and graphite, which are light in weight, have minimal deformation at high temperature, are corrosion resistant, have high mechanical strength and are easy to process.

[0025] (5) In the cross-linked polyolefin foaming device of the present invention, the openings for the sheet to pass through in the first accommodating space, the second accommodating space, and the third accommodating space increase in size upward and downward, which is conducive to adapting to the expansion of the sheet during the heating and foaming process. While ensuring that the hot air does not flow out too much, it also avoids the sheet from being stuck in the above-mentioned feed port or discharge port during movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is an overall schematic diagram of a cross-linked polyolefin foaming device according to an embodiment of the present invention;

[0027] Figure 2 A top view of a transmission mechanism involved in a cross-linked polyolefin foaming device according to an embodiment of the present invention;

[0028] Figure 3 This is a front view of a transmission mechanism involved in a cross-linked polyolefin foaming device according to an embodiment of the present invention;

[0029] Figure 4 The present invention is a schematic diagram of the heating system structure involved in a cross-linked polyolefin foaming device according to an embodiment of the present invention.

[0030] Figure 5 This is an installation position diagram of a spreading roller mechanism involved in a cross-linked polyolefin foaming device according to an embodiment of the present invention;

[0031] Figure 6 This is a schematic structural diagram of a spreading roller mechanism involved in a cross-linked polyolefin foaming device according to an embodiment of the present invention;

[0032] Figure 7 It is an enlarged view of the sealing structure involved in the spreading roller mechanism of an embodiment of the present invention;

[0033] Figure 8 The roll spreading mechanism of the present invention Figure 6 A partial enlarged view of

[0034] Fig. 9 It is a schematic diagram of the structure of a rotary joint involved in the roller spreading mechanism of an embodiment of the present invention;

[0035] In all the drawings, the same reference numerals represent the same technical features, specifically: 1-unwinding frame, 2-feeding traction roller, 3-transmission mechanism, 4-horizontal furnace, 5-hot air recovery device, 6-vertical furnace, 7-roller mechanism, 8-suction cup, 9-calendering roller, 10-cooling roller, 11-receiving traction roller, 12-correction roller, 13-rewinding frame;

[0036] 301-active roller, 302-passive roller, 303-conveyor mesh belt, 304-passive roller bracket, 305-telescopic device, 306-first transmission shaft, 307-bearing, 308-frequency conversion motor, 309-sprocket, 310-transmission chain, 311-U-shaped plate, 312-rolling bearing, 313-positioning screw, 314-active roller bracket;

[0037] 61-transition mechanism, 62-pre-foaming mechanism, 63-foaming mechanism, 64-furnace body; 611-first shell, 612-first accommodating space, 613-transition feed port, 614-transition discharge port, 615-first hot air channel, 616-first air inlet, 617-first air outlet, 618-first fan, 619-first heating rod group; 621-second shell, 622-second accommodating space, 623-pre-foaming feed port, 624-pre-foaming discharge port , 625-second hot air channel, 626-second air inlet, 627-second air outlet, 628-second fan, 629-second heating rod group; 631-third shell, 632-third accommodating space, 633-foaming feed inlet, 634-foaming outlet, 635-third hot air channel, 636-third air inlet, 637-third air outlet, 638-third fan, 639-third heating rod group; 641-vertical feed inlet, 642-vertical outlet;

[0038] 701-first unfolding roller, 702-second unfolding roller, 703-sealing structure, 704-seat bearing, 705-drive sprocket, 706-drive chain, 707-motor, 708-rotating joint, 709-bearing seat, 710-bearing, 711-synchronous gear; 7031-fully sealed steel plate, 7032-first sealing ring, 7033-sealing cover, 7034-second sealing ring, 7035-sealing ring; 7081-cold water external inlet, 7082-hot water external outlet. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Figure 1 FIG. 1 is an overall schematic diagram of a cross-linked polyolefin foaming device according to an embodiment of the present invention. Figure 1As shown, the cross-linked polyolefin foaming device of the present invention comprises a horizontal furnace 4 and a vertical furnace 6 for the sheet to pass through in sequence for heating and foaming, and the vertical furnace 6 is arranged below the horizontal furnace 4. The sheet unwound by the unwinding rack 1 is conveyed to the horizontal furnace 4 by the feeding traction roller 2, and is uniformly preheated in the horizontal direction, and then enters the vertical furnace 6 in the vertical direction for foaming, so that the foamed sheet is uniformly heated, expanded and foamed. The foamed sheet includes a cross-linked polyolefin sheet, and the foaming device of the present invention is used for foaming cross-linked polyolefin.

[0041] The horizontal furnace 4 can be a split structure, including multiple independent furnaces, with a gap between two adjacent furnaces to set a cooling device, and intermittent heating of the foamed sheet can be achieved through the setting of the furnace and the cooling device. The inlet and outlet of the horizontal furnace 4 for the foamed sheet to enter and exit are respectively located on the furnaces at both ends.

[0042] A transmission mechanism 3 is provided in the horizontal furnace 4 to transport the foamed sheet horizontally. The foamed sheet passes through each furnace chamber in sequence on the transmission mechanism 3 and finally enters the vertical furnace 6. Figure 2 and Figure 3 The top view and the front view of the transmission mechanism involved in the foaming device of the present invention are respectively shown. The transmission mechanism 3 includes an active roller 301 and a passive roller 302, and a conveyor belt 303 connecting the active roller 301 and the passive roller 302. The conveyor belt 303 is annularly installed on the active roller 301 and the passive roller 302 at both ends, so that the conveyor belt 303 forms a closed-loop conveying form between the active roller 301 and the passive roller 302. Among them, a first transmission shaft 306 is provided at the center of the active roller 301, and the active roller 301 and the first transmission shaft 306 are fixedly connected by sleeve connection. Bearings 307 are provided on both sides of the first transmission shaft 306, and the first transmission shaft 306 is fixedly connected to the bearing 307 by sleeve connection. In addition, preferably, an active roller bracket 314 is provided at the bottom of the active roller 301 for fixing the active roller 301. A second transmission shaft is provided in the passive roller 302, and the passive roller 302 is also fixedly connected to the second rotating shaft by sleeve connection, and the second transmission shaft is also fixedly connected to the rolling bearing 312 by sleeve connection.

[0043] Furthermore, one end of the first transmission shaft 306 passes through the bearing 307, and the top extends out of the bearing 307 for a certain distance, so that a sprocket 309 is arranged on the top of the first transmission shaft 306, and the sprocket 309 is connected to the variable frequency motor 308 through a transmission chain 310. A transmission sprocket is arranged at one end of the variable frequency motor 308, and the transmission chain 310 realizes transmission through the sprocket 309 and the transmission sprocket on the variable frequency motor 308.

[0044] Furthermore, a passive roller bracket 304 is provided at the bottom of the conveyor mesh belt 303, and a U-shaped plate 311 is provided on both lateral sides of the passive roller bracket 304, and telescopic devices 305 are respectively fixed on the U-shaped plates 311 on both sides, so the telescopic devices 305 are also provided on both lateral sides of the conveyor mesh belt 303, wherein one end of the telescopic device 305 is fixedly connected to the U-shaped plate 311 on the bracket, and the other end is fixedly connected to the rolling bearing 312 of the passive roller 302. The rolling bearing 312 is preferably a slidable rolling bearing device, and a positioning screw 313 is longitudinally provided in the rolling bearing 312.

[0045] Among them, the telescopic device 305 is used to push the slidable rolling bearing 312 to move longitudinally on the U-shaped plate 311, thereby changing the position of the passive roller 302, so as to achieve the effect of adjusting the tension of the conveyor mesh belt 303; the positioning screw 313 is used to fix the rolling bearing 312 and the telescopic device 305 by longitudinally tightening after the tension of the conveyor mesh belt 303 reaches the requirement, so that a stable rolling friction force is generated between the conveyor mesh belt with appropriate tension and the active roller and the passive roller.

[0046] Of course, the transmission speed of the conveyor mesh belt 303 is regulated by the control system. It is necessary to appropriately adjust the relative speeds of the active roller 301 and the passive roller 302 to increase the conveying efficiency while preventing the sheet from moving and deviating on the conveyor mesh belt. On the one hand, the sheet is evenly conveyed on the conveyor mesh belt, and on the other hand, it ensures that the sheet does not deviate when entering the subsequent foaming link, so that the foaming in the subsequent steps is uniform, without adhesion or breakage, and ultimately improves the yield rate.

[0047] Preferably, the telescopic device is an adjusting cylinder. Of course, other telescopic devices can also be selected as long as they can generate tension to ensure that the passive roller 302 and the conveyor belt 303 are tightened.

[0048] Preferably, the mesh size of the conveyor mesh belt 303 is 80-200 meshes, and the shape is square, diamond, rectangle, etc. If the mesh size of the conveyor mesh belt 303 is less than 80 meshes, the sheet is not easily heated when the steel mesh conveys the sheet, which affects the foaming effect of the sheet. At the same time, the weight of the entire mesh belt is too heavy, and the transmission motor is under heavy load and is easy to be damaged; if the mesh size of the conveyor mesh belt 303 is greater than 200 meshes, the mesh belt is easy to pull and deform, affecting the transmission of the sheet.

[0049] When the transmission mechanism 3 is working, the telescopic device 305 contracts the tension, and the telescopic device 305 pushes the slidable rolling bearing 312 to move longitudinally on the U-shaped plate 311, thereby changing the position of the passive roller 302 to adjust the tension of the conveyor mesh belt 303. After the tension reaches the set requirement, the positioning screw rod 313 is inserted and tightened to fix the rolling bearing 312 and the telescopic device 305; the passive roller 302 is acted on by the second transmission shaft in the passive roller 302, so that the passive roller 302, the active roller 301 and the conveyor mesh belt 303 are closely fitted, and the conveyor mesh belt 303 with appropriate tension generates rolling friction with the active roller 301 and the passive roller 302; then the foam sheet is The material is placed on the conveyor mesh belt 303 for transmission, and the frequency conversion motor 308 drives the transmission chain 310 through the transmission sprocket, and the transmission of the transmission chain 310 drives the sprocket 309 to rotate, and then drives the first transmission shaft 306, so that the active roller 301 rotates along the bearing 307; the conveyor mesh belt 303 connects the active roller 301 and the passive roller 302, so that when the active roller 301 is running, the passive roller 302 also runs accordingly, and the friction force of the active roller 301, the passive roller 302 and the conveyor mesh belt 303 drives the conveyor mesh belt 303 to transmit, thereby driving the conveyor mesh belt 303 to operate in a closed loop, so as to achieve the purpose of conveying the foaming material.

[0050] Furthermore, if Figure 1 , Figure 4 and Fig. 9 As shown, the vertical furnace 6 includes a furnace body 64, a heating system and a roll spreading mechanism. A vertical feed port 641 is provided at the upper end of the furnace body 64, and the inlet is connected to the outlet of the horizontal furnace. The sheet output from the outlet of the horizontal furnace 4 enters the vertical furnace 6 through the vertical feed port 641 and is transported downward in a vertical state under the action of gravity; a vertical discharge port 642 is provided at the lower end of the furnace body 64, which is connected to the vertical feed port 641, and is used for the sheet to pass through and be output.

[0051] The heating system is arranged in the furnace body 64 to form a heating field in the furnace body 64 for the foaming sheet to pass through. Figure 4 The heating system includes a transition mechanism 61, a pre-foaming mechanism 62 and a foaming mechanism 63 which are arranged in sequence from top to bottom.

[0052] Specifically, the transition mechanism 61 includes an external first shell 611, and a first accommodating space 612 is defined inside the first shell 611. First hot air channels 615 are respectively provided on both sides of the first accommodating space 612, and the first shell 611 is suspended inside the furnace through the support of the first hot air channels 615; a transition feed port 613 and a transition discharge port 614 connected to the first accommodating space 612 are respectively provided at the upper and lower ends of the first shell 611; a first air inlet 616 connected to the furnace is provided at one end of the first hot air channel 615, and a first air outlet 617 connected to the first accommodating space 612 is provided at the other end; an end of the first hot air channel 615 close to the first air inlet 616 is fixedly connected to the furnace body 64, and an end of the first hot air channel 615 close to the first air outlet 617 is fixedly connected to the first shell 611; a first fan 618 is provided on one side of the first hot air channel 615 close to the first air inlet 616, and a first heating rod group 619 is provided on one side close to the first air outlet 617;

[0053] The pre-foaming mechanism 62 includes a second shell 621, which defines a second accommodating space 622 inside. Second hot air channels 625 are respectively provided on both lateral sides of the second accommodating space 622. The second shell 621 is suspended inside the furnace through the support of the second hot air channels 625; the second shell 621 is respectively provided with a pre-foaming feed port 623 and a pre-foaming outlet port 624 connected to the second accommodating space 622 at the upper and lower ends; one end of the second hot air channel 625 is provided with a second air inlet 626 connected to the furnace, and the other end is provided with a second air outlet 627 connected to the second accommodating space 622. One end of the second hot air channel 625 close to the second air inlet 626 is fixedly connected to the furnace body 64, and one end close to the second air outlet 627 is fixedly connected to the second shell 621; a second fan 628 is provided on one side of the second hot air channel 625 close to the second air inlet 626, and a second heating rod group 629 is provided on the side close to the second air outlet 627;

[0054] The foaming mechanism 63 includes a third shell 631, which defines a third accommodating space 632 inside. Third hot air channels 635 are respectively provided on both lateral sides of the third accommodating space 632. The third shell 631 is suspended inside the furnace through the support of the third hot air channels 635; a foaming feed port 633 and a foaming outlet 634 connected to the third accommodating space 632 are respectively provided on the upper and lower sides of the third shell 631; a third air inlet 636 connected to the furnace is provided at one end of the third hot air channel 635, and a third air outlet 637 connected to the third accommodating space 632 is provided at the other end; an end of the third hot air channel 635 close to the third air inlet 636 is fixedly connected to the furnace body 64, and an end of the third hot air channel 635 close to the third air outlet 637 is fixedly connected to the third shell 631; a third fan 638 is provided on one side of the third hot air channel 635 close to the third air inlet 636, and a third heating rod group 639 is provided on one side close to the third air outlet 637.

[0055] It should be noted that the transition feed port 613 and the transition discharge port 614 are aligned with the vertical feed port 641 and the vertical discharge port 642 on the furnace body 64; the pre-foaming feed port 623 and the pre-foaming discharge port 624 are aligned with the vertical feed port 641 and the vertical discharge port 642 on the furnace body 64; the foaming feed port 633 and the foaming discharge port 634 are aligned with the vertical feed port 641 and the vertical discharge port 642 on the furnace body 64.

[0056] Preferably, the transition feed port 613, the transition outlet port 614, the pre-foaming feed port 623, the pre-foaming outlet port 624, the foaming feed port 633 and the foaming outlet port 634 have no contact with the sheet material, and the openings increase successively, which is conducive to adapting to the expansion of the sheet material during the heating and foaming process, while ensuring that the hot air does not flow out too much, and avoiding the sheet material from getting stuck in the above-mentioned feed port or outlet port during movement.

[0057] Preferably, the total power of the first heating rod group 619 is less than the total power of the second heating rod group 629 , and the total power of the second heating rod group 629 is less than the total power of the third heating rod group 639 .

[0058] Preferably, the first hot air channel 615 is symmetrically arranged on both sides of the first accommodating space 612 , the second hot air channel 625 is symmetrically arranged on both sides of the second accommodating space 622 , and the third hot air channel 635 is symmetrically arranged on both sides of the third accommodating space 632 .

[0059] like Figure 5 As shown, the roll-unfolding mechanism 7 is respectively arranged obliquely at two opposite side walls of the vertical foaming and heating device, and includes at least one pair of roll-unfolding rollers arranged in the furnace body 64 to clamp and unfold the foaming sheet. The two roll-unfolding rollers are located on both sides of the foaming sheet in the furnace body 64, and can unfold and clamp the foaming sheet.

[0060] Specifically, Figure 6 The roll-unfolding mechanism 7 includes a first unfolding roller 701 and a second unfolding roller 702 of different lengths, which are used to clamp and unfold the foam sheet, wherein one end of the first unfolding roller 701 and the second unfolding roller 702 are located inside the vertical furnace 6, and the other end is located outside the vertical furnace 6, and a sealing structure 703 is provided at the junction of the roll-unfolding mechanism 7 and the vertical furnace 6, and the sealing structure 703 is provided inside the side wall of the vertical furnace 6. Figure 7 The sealing structure 703 includes a fully sealed steel plate 7031 , a first sealing ring 7032 , a sealing cover 7033 , a second sealing ring 7034 and a sealing ring 7035 .

[0061] The fully sealed steel plate 7031 is assembled from several A3 steel plates. A boss-shaped first sealing ring 7032 is provided at the junction of the fully sealed steel plate 7031 and the first unfolding roller 701, so that there is no direct contact between the fully sealed steel plate 7031 and the first unfolding roller 701. The first sealing ring 7032 includes a boss structure and a cylindrical structure. The boss structure is pressed on one side of the fully sealed steel plate 7031. A sealing cover 7033 is provided on the boss structure. The first sealing ring 7032 is fixed to the fully sealed steel plate 7031 through the sealing cover 7033. A second sealing ring 7034 is provided inside the fully sealed steel plate 7031. The second sealing ring 7034 is seamlessly attached to the inside of the fully sealed steel plate 7031. A sealing ring 7035 is provided inside the second sealing ring 7034. The cylindrical structure of the first sealing ring 7032 passes through the second sealing ring 7034 and the sealing ring 7035 in sequence.

[0062] The first unrolling roller 701 passes through the sealing cover 7033, the first sealing ring 7032, the second sealing ring 7034 and the sealing ring 7035 from the outside to the inside in sequence, wherein the first unrolling roller 701 has no direct contact with the second sealing ring 7034 and the sealing ring 7035. The sealing cover 7033 and the sealing ring 7035 are fixed by bolts.

[0063] The second unfolding roller 702 passes through the fully sealed steel plate 7031 and the second sealing ring 7034. The second sealing ring 7034 can rotate around the sealing ring 7035. When the second unfolding roller 702 moves relative to the first unfolding roller 701 as the axis, the second sealing ring 7034 also moves synchronously.

[0064] In the embodiment of the present invention, the fully sealed steel plate 7031 is preferably two layers. Of course, the method of setting more than two layers is also within the protection scope of the present invention. Through at least two sets of seals, on the one hand, the oil smoke generated by the foam sheet will not leak, achieving an excellent sealing effect; on the other hand, the heat energy in the vertical furnace will not be lost.

[0065] Preferably, the first sealing ring 7032 and the second sealing ring 7034 are made of high temperature resistant mica plate and graphite, which are resistant to high temperature, have good mechanical processing and strength. Since the second unfolding roller 702 needs to make relative displacement with the first unfolding roller 701 as the axis, the selection and structure of the sealing material have a great influence on the sealing effect. The seal of the unfolding roller mechanism of the present invention adopts at least two sets of sealing ring structures, which are made of the above materials, are light in weight, have extremely small deformation at high temperature, are corrosion resistant, have high mechanical strength, and are easy to process. In addition, the unfolding roller is made of special materials, and the deformation at high temperature is also extremely small. In this way, the overall operation of the unfolding mechanism is stable and easy to seal.

[0066] Preferably, the first unrolling roller 701 and the second unrolling roller 702 are made of high temperature resistant and corrosion resistant hollow rods.

[0067] The unfolding roller mechanism 7 of the present invention has an unfolding roller that enters the foaming furnace through the wall and adopts a fully enclosed sealing structure. On the one hand, the outer periphery is sealed by a fully enclosed steel plate. At the inlet and outlet positions where the unfolding roller mechanism enters the wall, sealing rings, sealing rings and sealing covers are designed in sequence to realize a fully enclosed environment. This not only reduces oil smoke during foaming of the foamed semi-finished product and achieves a leak-proof effect, but also reduces the wear of the equipment.

[0068] One end of the fully sealed steel plate 7031 extends out of the vertical foaming furnace wall and is provided with at least two bearing seats 704, which are connected to the first unfolding roller 701 arranged outside the furnace wall. The first unfolding roller 701 and the second unfolding roller 702 arranged outside the furnace wall are also provided with an integrated synchronous gear 711 and an integrated bearing seat 709, which connect the first unfolding roller 701 and the second unfolding roller 702 at the same time, wherein the bearing seat 709 is preferably two pieces. Each bearing seat 709 is provided with at least two groups of bearings 710, at least one group is used to fix the first unfolding roller 701, and at least one group is used to fix the second unfolding roller 702.

[0069] In the roller unfolding mechanism 7 of the present invention, the first unfolding roller 701 is connected to the seat bearing 704 and the bearing seat 709 at the same time, so that the first unfolding roller 701 can only rotate at a fixed position, and the bearing seat 709 can rotate around the first unfolding roller 701. Therefore, the second unfolding roller 702 installed on the bearing seat 709 also rotates accordingly, so that the gap between the first unfolding roller 701 and the second unfolding roller 702 in the vertical direction changes, and when the foam sheet passes through the middle of the first unfolding roller 701 and the second unfolding roller 702, different friction forces are generated due to the change in the gap.

[0070] The first unfolding roller 701 is provided with a transmission sprocket 705, and the transmission sprocket 705 is connected to the output shaft of the motor 707 through a transmission chain 706 to form a transmission system. The motor 707 is preferably a transmission variable frequency reduction motor. The transmission system of the unfolding roller mechanism is powered by the motor 707, which drives the first unfolding roller 701 to rotate, and then the first unfolding roller 701 and the second unfolding roller 702 are rotated in opposite directions from outside to inside through the synchronous gear 711. When the foaming sheet passes through the middle of the first unfolding roller 701 and the second unfolding roller 702, the unfolding rollers rotating in opposite directions and the foaming sheet unfold to both sides horizontally under the action of friction; and by adjusting the rotation speed of the unfolding roller mechanism on both sides of the vertical foaming furnace wall and the relative position of the second unfolding roller 702, the foaming sheet is unfolded in a flat state and transported downward in the center of the vertical furnace, achieving the effect of continuous and stable production. In the roll spreading mechanism of the present invention, the motor is connected to the spreading roller through a sprocket for transmission, and the two spreading rollers are made to rotate in opposite directions through the meshing of synchronous gears, so as to expand the width of the foamed sheet semi-finished product.

[0071] Preferably, if Fig. 9 The first unrolling roller 701 and the second unrolling roller 702 are provided with corresponding rotating joints 708 at the top of one end outside the furnace wall, and the rotating joints include cold water inlets 7081 and hot water outlets 7082 in different directions. The cold water inlet 7081 is used to pass cooling water into the hollow first unrolling roller 701 and the second unrolling roller 702, and the water after heat exchange flows out through the hot water outlet 7082. The rotating joint 708 realizes the cooling of the circulating water of the rotating unrolling roller, so as to prevent the foam sheet from sticking to the unrolling roller.

[0072] In summary, the roll spreading mechanism of the present invention solves the problem of product scrapping caused by overlapping and sticking of foam sheets in a vertical furnace and the quality problem of finished products caused by uneven heating, thereby improving the yield of products. At the same time, a new sealing technology is adopted to avoid air pollution, equipment corrosion, and heat loss in the production site caused by oil fume leakage, and also achieve the effect of energy saving and consumption reduction. High-temperature resistant mica plates, graphite and other materials are used, and the sealing structure is innovated to overcome the characteristics of high temperature resistance and easy deformation, and the sealing performance is good.

[0073] Preferably, the foaming furnace of the present invention further comprises an adsorption mechanism disposed at the vertical discharge port 642 of the furnace body 64, to further adsorb and unfold the foaming sheet. In this embodiment, the adsorption mechanism comprises a suction cup 8, which is distributed on one side of the foaming sheet at the vertical discharge port 642 of the furnace body 64. One or more suction cups 8 may be provided according to the width of the foaming sheet.

[0074] Preferably, the foaming furnace of the present invention further comprises a hot air recovery device 5 disposed between the vertical furnace 6 and the horizontal furnace 4, for recovering the hot air flowing out from above the furnace body 64 of the vertical furnace 6 and conveying it back into the furnace body 64, thereby achieving energy saving.

[0075] like Figure 1 As shown, further, the foaming furnace of the present invention also includes a feeding device for conveying the foamed sheet to the horizontal furnace 4, and a discharging device for pulling the foamed sheet out of the vertical furnace 6. Among them, the feeding device includes an unwinding frame 1, and a feeding traction roller 2 on a transmission mechanism 3 for pulling the foamed sheet on the unwinding frame 1 to the horizontal furnace 4. The feeding traction roller 2 is arranged in the conveying direction of the foamed sheet, and is located between the unwinding frame 1 and the horizontal furnace 4.

[0076] The discharging device includes a calendering roller 9, a cooling roller 10, a deflection correction roller 12 and a winding frame 13 which are arranged in sequence along the output direction of the foamed sheet and arranged at the vertical discharging port 642 of the furnace body 64 of the vertical furnace 6, and at least one pair of receiving and pulling rollers 11. The receiving and pulling rollers 11 are arranged at one or more positions between the calendering roller 9 and the cooling roller 10, between the cooling roller 10 and the deflection correction roller 12, and between the deflection correction roller 12 and the winding frame 13 to pull the foamed sheet. The foamed sheet output from the vertical furnace 6 is wound on the winding frame 13 after being calendered and shaped by the calendering roller 9, cooled and pulled by the cooling roller 10, and corrected by the deflection correction roller 12.

[0077] When the foaming furnace of the present invention is working, the cross-linked polyolefin sheet (in roll form) is loaded onto the unwinding rack 1, and after unwinding, it is pulled into the horizontal furnace 4 by the feed traction roller 2; the polyolefin sheet is preheated and foamed in the horizontal furnace 4 and enters the vertical furnace 6, and after foaming and unfolding, it is output from the bottom of the vertical furnace 6, and is rolled up on the winding rack 13 after passing through the discharging device.

[0078] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A cross-linked polyolefin foaming device, comprising a vertical furnace (6) through which a sheet passes to be heated and foamed, characterized in that: The vertical furnace (6) has a spreading roller mechanism (7) disposed on two opposite side walls thereof; and, The roll spreading mechanism (7) comprises a first spreading roller (701) and a second spreading roller (702); one end of the first spreading roller (701) and the second spreading roller (702) are located inside the vertical furnace (6), and the other end is arranged outside the vertical furnace (6), and a sealing structure (703) is provided at the junction of the spreading roller and the vertical furnace (6); The sealing structure (703) is arranged inside the side wall of the vertical furnace (6), and the sealing structure (703) comprises a fully sealed steel plate (7031), a first sealing ring (7032), a sealing cover (7033), a second sealing ring (7034) and a sealing ring (7035); The first unfolding roller (701) passes through the sealing cover (7033) of the first sealing structure, the first sealing ring (7032), the fully sealed steel plate (7031), the second sealing ring (7034), the sealing ring (7035), and the sealing ring (7035) of the second sealing structure, the second sealing ring (7034), the fully sealed steel plate (7031), the first sealing ring (7032), and the sealing cover (7033) in sequence from the outside to the inside; The second unfolding roller (702) passes through the fully sealed steel plate (7031), the second sealing ring (7034) of the first layer of sealing structure, the second sealing ring (7034) and the fully sealed steel plate (7031) of the second layer of sealing structure in sequence from the outside to the inside; when the second unfolding roller (702) is relatively displaced with the first unfolding roller (701) as the axis, it can drive the second sealing ring (7034) to rotate around the sealing ring (7035).

2. The cross-linked polyolefin foaming device according to claim 1, characterized in that: The first sealing ring (7032) comprises a boss structure and a cylindrical structure, the boss structure is pressed on one side of the fully sealed steel plate (7031), and a sealing cover (7033) is provided on the boss structure; a second sealing ring (7034) is provided on the inner side of the fully sealed steel plate (7031), and a sealing ring (7035) is provided on the inner side of the second sealing ring (7034); the cylindrical structure of the first sealing ring (7032) passes through the second sealing ring (7034) and the sealing ring (7035) in sequence.

3. The cross-linked polyolefin foaming device according to claim 1, characterized in that: The first sealing ring (7032) and the second sealing ring (7034) are made of high temperature resistant mica plate and graphite material.

4. The cross-linked polyolefin foaming device according to claim 1, characterized in that: The outer ends of the first unfolding roller (701) and the second unfolding roller (702) are provided with corresponding rotating joints (708), and each rotating joint (708) comprises a cold water external inlet (7081) and a hot water external outlet (7082) in different directions.

5. The cross-linked polyolefin foaming device according to any one of claims 1 to 4, characterized in that: The foaming device also includes a horizontal furnace (4) arranged above the vertical furnace (6), wherein a transmission mechanism (3) is provided in the horizontal furnace (4), and the transmission mechanism includes an active roller (301), a passive roller (302), and a conveyor mesh belt (303) that connects the two to form a closed-loop conveying.

6. The cross-linked polyolefin foaming device according to claim 5, characterized in that: A passive roller bracket (304) is provided at the bottom of the conveyor mesh belt (303); U-shaped plates (311) are provided on both lateral sides of the passive roller bracket (304); and telescopic devices (305) are respectively fixed on the U-shaped plates (311); one end of the telescopic device (305) is fixedly connected to the U-shaped plate (311) on the bracket, and the other end is fixedly connected to the rolling bearing (312) of the passive roller (302).

7. The cross-linked polyolefin foaming device according to any one of claims 1 to 4 or 6, characterized in that: The vertical furnace (6) also has a heating system, which includes a transition mechanism (61), a pre-foaming mechanism (62) and a foaming mechanism (63) which are sequentially arranged at intervals from top to bottom to form an independent temperature section.

8. The cross-linked polyolefin foaming device according to claim 7, characterized in that: The transition mechanism (61), pre-foaming mechanism (62) and foaming mechanism (63) all include an external shell, the interior of the shell defines a accommodating space, hot air channels are respectively provided on both lateral sides of the accommodating space, and the shell is suspended inside the furnace through the support of the hot air channels; the upper and lower ends of the shell are respectively provided with a feed port and a discharge port connected to the accommodating space; one end of the hot air channel is provided with an air inlet connected to the furnace, and the other end is provided with an air outlet connected to the accommodating space; one end of the hot air channel close to the air inlet is fixedly connected to the furnace body, and the other end of the hot air channel close to the air outlet is fixedly connected to the shell; a fan is provided on the side of the hot air channel close to the air inlet, and a heating rod group is provided on the side close to the air outlet.

9. The cross-linked polyolefin foaming device according to claim 8, characterized in that: The total power of the heating rod group in the transition mechanism (61) is less than the total power of the heating rod group in the pre-foaming mechanism (62), and the total power of the heating rod group in the pre-foaming mechanism (62) is less than the total power of the heating rod group in the foaming mechanism (63).

10. The cross-linked polyolefin foaming device according to any one of claims 1 to 4 or 6, 8, and 9, characterized in that: It also comprises a feeding device, which comprises an unwinding frame (1) and a feeding traction roller (2) for traction the foamed sheet on the unwinding frame (1) to the transmission mechanism (3).

11. The cross-linked polyolefin foaming device according to any one of claims 1 to 4 or 6, 8, and 9, characterized in that: It also includes a discharging device for pulling the foamed sheet out of the vertical furnace (6), the discharging device including a calendering roller (9), a cooling roller (10), a deviation correction roller (12), a winding frame (13) and at least one pair of material receiving and pulling rollers (11) which are arranged in sequence at the exit of the vertical furnace (6).

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