Production equipment and production method of high-voltage-resistant high-performance aramid paper

Abstract

The invention discloses production equipment and a production method of high-voltage-resistant high-performance aramid paper, and particularly relates to the technical field of aramid paper.The production equipment of the high-voltage-resistant high-performance aramid paper comprises a main extrusion roller, a protective cover is arranged above the main extrusion roller, and multiple rows of auxiliary extrusion rollers are arranged in the protective cover; the number of the auxiliary extrusion rollers in each row is multiple, a gap exists between every two adjacent auxiliary extrusion rollers in the same row, and every two adjacent rows of auxiliary extrusion rollers are distributed in a staggered mode. The multiple rows of auxiliary extrusion rollers are arranged at the outer end of the main extrusion roller, the number of the auxiliary extrusion rollers in each row is multiple, all the auxiliary extrusion rollers are independently matched with the main extrusion roller to conduct hot pressing work, even if the thicknesses of aramid paper in the contact positions of all the auxiliary extrusion rollers are different, hot pressing work of all the auxiliary extrusion rollers cannot affect one another, and the hot pressing efficiency is improved. The poor compounding effect caused by uneven thickness of the aramid paper is avoided, and the forming effect of the aramid paper is improved.

Description

Technical Field

[0001] The invention relates to the technical field of aramid paper, and in particular to a production device and a production method for high-voltage resistant and high-performance aramid paper. Background Art

[0002] High-voltage resistant and high-performance aramid paper belongs to aramid composite materials, which are mainly composed of two categories: meta-aramid insulation paper and para-aramid insulation paper. Meta-aramid paper is ahead of para-aramid paper in insulation performance. Meta-aramid is a high molecular weight polymer obtained by polymerization of isophthaloyl chloride and meta-phenylenediamine, abbreviated as 7PMIA in English. PMIA polymer solution is used as raw material to make precipitated fibers through precipitation process.

[0003] PMIA polymer solution spinning can be made into high-strength and high-modulus fibers, which can be made into chopped fibers after further processing; precipitated fibers and chopped fibers are two important raw materials for preparing high-voltage resistant aramid paper. Precipitated fibers and chopped fibers are made into aramid fiber paper after a certain proportion.

[0004] Aramid fiber paper needs to be hot-pressed during the production process. Multi-layer aramid paper is compounded into a firm, tight, and stronger aramid fiber paper through high temperature and high pressure. The hot pressing equipment in the prior art is mainly composed of two hot pressing rollers with heating function. The two hot pressing rollers are pressed against each other to achieve hot pressing, such as an aramid paper hot press machine with publication number CN218812878U in the prior art.

[0005] The two hot pressing rollers distributed up and down apply vertical pressure to the aramid paper. The hot pressing roller itself is a whole and cannot bend or tilt during operation. In this way, if the thickness of the aramid paper is uneven during the hot pressing process, under the support of the thicker parts, other thinner parts will be difficult to be fully pressurized, which will ultimately lead to poor composite effect of aramid fiber paper. Summary of the invention

[0006] The purpose of the present invention is to provide a production device and a production method for high-voltage resistant and high-performance aramid paper. Each auxiliary extrusion roller independently cooperates with the main extrusion roller to perform hot pressing work. Even if the thickness of the aramid paper at the contact part of each auxiliary extrusion roller is different, the hot pressing work between the auxiliary extrusion rollers will not affect each other, thereby avoiding uneven thickness of the aramid paper and resulting in poor composite effect.

[0007] In order to achieve the above-mentioned object, the present invention provides the following technical solution: a production device for high-voltage resistant and high-performance aramid paper, comprising a main squeezing roller, a protective cover is provided above the main squeezing roller, a plurality of rows of auxiliary squeezing rollers are provided inside the protective cover, and a plurality of auxiliary squeezing rollers are provided in each row, the auxiliary squeezing rollers are in contact with the outer end of the main squeezing roller, and a pressure component is provided on the outer side of the auxiliary squeezing roller;

[0008] There is a gap between two adjacent auxiliary squeezing rollers in the same row, and the distribution of the auxiliary squeezing rollers in the two adjacent rows is staggered, wherein the auxiliary squeezing rollers in one row correspond to the gaps of the auxiliary squeezing rollers in the other row, and the pressure assembly includes a bracket, and the auxiliary squeezing roller is located inside the corresponding bracket and is rotatably connected to the inner wall of the bracket;

[0009] Two telescopic rods and two springs are arranged between the bracket and the inner wall of the protective cover. The two ends of the telescopic rods are respectively connected to the inner wall of the protective cover and the bracket, and the springs are similar. The two springs are respectively sleeved on the outer ends of the two telescopic rods. The springs are in a compressed state during the hot pressing process.

[0010] Furthermore, the auxiliary extrusion roller includes an auxiliary heat-conducting tube made of metal, both ends of the auxiliary heat-conducting tube are provided with end covers, the end covers are connected to the auxiliary heat-conducting tube by bolts, an air guide pipe is fixed on the end cover, one end of the air guide pipe is communicated with the auxiliary heat-conducting tube, and the air guide pipe is movably connected to the bracket through a sealed bearing.

[0011] Furthermore, both sides of the bracket are provided with closed cylinders, the other ends of the two air guide tubes are respectively connected to the two closed cylinders, and a high temperature resistant hose is fixedly provided on the top of the closed cylinder;

[0012] A plurality of steam channels for circulating high-temperature steam are fixedly provided at the outer end of the protective cover, each steam channel corresponds to a row of auxiliary extrusion rollers, one end of the hose is connected to the corresponding steam channel, and removable closing covers are provided at both ends of the steam channel, and pipes for conducting steam are fixedly provided on the closing covers.

[0013] Furthermore, a base is provided at the bottom of the main squeezing roller, and connecting plates are fixedly provided at the four corners of the protective cover. A lifting rod is provided at the top of the connecting plate. The connecting plate and the lifting rod can be detached and separated, and a connecting arm is provided at the top of the lifting rod;

[0014] A hydraulic cylinder is provided on one side of the lifting rod, the bottom end of the hydraulic cylinder is connected to the top of the base, the piston rod of the hydraulic cylinder and the lifting rod are connected by a connecting arm, the two ends of the connecting arm are respectively connected to the top of the lifting rod and the top of the piston rod of the hydraulic cylinder, the extension and retraction of the hydraulic cylinder can drive the lifting rod and the connecting plate and then drive the protective cover.

[0015] Furthermore, two fixed seats are fixedly provided on the top of the base, and the main extrusion roller is located between the two fixed seats. The main extrusion roller includes a main heating tube made of metal, and removable sealing covers are provided at both ends of the main heating tube. A hollow shaft is fixedly provided on the two sealing covers, and the two hollow shafts are rotatably connected to the two fixed seats respectively. The hollow shaft passes through the fixed seat and is movably connected to the fixed seat through a sealed bearing.

[0016] Furthermore, both fixing seats are provided with sealing covers, and an external pipe with a valve is fixedly provided at the bottom of the sealing cover. The two hollow shafts are respectively connected to the inside of the two sealing covers, so as to input high-temperature steam into the main extrusion roller.

[0017] Furthermore, a dust suction channel is fixedly provided at the top of the base, the dust suction channel is located between the two fixed seats, a negative pressure pipe is fixedly provided at the outer end of the dust suction channel, and a negative pressure pump is externally connected to the negative pressure pipe to extract the air in the dust suction channel, and a dust suction groove is opened at the top of the dust suction channel, and the dust suction groove is located directly below the main extrusion roller;

[0018] Guide rollers are arranged on both sides of the main extrusion roller, and both ends of the guide rollers are rotatably connected with end plates, and the two end plates are respectively fixed on two fixed seats.

[0019] The present invention also includes a method for producing the high-voltage resistant high-performance aramid paper, and the specific steps are as follows:

[0020] S1: meta-aramid chopped fiber pretreatment;

[0021] S1.1: Meta-aramid short-cut fibers are prepared by neutralizing isophthaloyl chloride with meta-phenylenediamine as raw materials. During the preparation, isophthaloyl chloride is added dropwise to meta-phenylenediamine, and the mixture is stirred in a reactor. The mixture is reacted at -45°C for 30 minutes, and then an excess of organic solvent is added. The mixture is stirred to obtain a meta-aramid polymer solution. The mixture is then broken into a gel by a homogenizer, and finally deionized water is added and stirred to obtain a meta-aramid nanofiber solution. The solution is spun into long and thin fiber filaments by a spinning machine, and finally cut into 5 mm or 6 mm long meta-aramid short-cut fibers;

[0022] S1.2: Use anionic surfactant or a combination of anionic surfactant and neutral surfactant to soak the meta-aramid short fibers for pretreatment. Sodium dodecylbenzene sulfonate can be used as an anionic surfactant, and sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether can be used as a compound surfactant. When using the above-mentioned ionic surfactants, the recommended concentration is 5E-4mol / L to 5E-3mol / L, the temperature is room temperature, the soaking time is 0.5h, and then washed and dried;

[0023] S2: meta-aramid fibrid pretreatment;

[0024] S2.1: using m-phenylenediamine and isophthaloyl chloride as raw materials to prepare meta-aramid fibrids, preparing a meta-aramid nanofiber solution in the same manner as in S1.1, and grinding the solution into fibrids by a disc mill;

[0025] S2.2: Pre-treat the meta-aramid fibrid by soaking it with an anionic surfactant or a combination of an anionic surfactant and a neutral surfactant, in the same manner as in S1.2;

[0026] S3: adding the meta-aramid chopped fibers treated by S1 into a fiber deflaker for deflaking, and then adding the meta-aramid fibrids treated by S2 for secondary deflaking to obtain a suspension, wherein the mass ratio of the meta-aramid chopped fibers to the fibrids during deflaking is 4:6 to 6:4, i.e., the proportion of the fibrids is 40% to 60%, and the speed of the deflaker is 10000 r / min-20000 r / min;

[0027] S4: The suspension obtained in S3 is transferred to a circular automatic paper former for dehydration and forming into aramid base paper. During the forming, a dispersant is added to the suspension for dispersion. The dispersant is polyethylene oxide, and the added amount is 0.05 to 0.05 of the mass of the meta-aramid chopped fiber and meta-aramid pulp system. The evenly dispersed suspension is added to the circular automatic paper former for dehydration and forming. A circular roller is used for dehydration and forming. The paper is placed in a vacuum dryer for dehydration at a pressure of 0.1 MPa and a temperature of 95°C. The paper is then demoulded and placed in a 90°C oven for drying for 2 hours, and the weight is measured. The paper is then placed back in the oven and the weight is measured every half an hour. When the difference between the two weights is less than 0.3 mg, the paper is taken out and sealed in a fresh-keeping bag to obtain the aramid base paper. The final weight of the aramid base paper is 25-150g / m 2 ;

[0028] S5: Using the above-mentioned high-voltage resistant and high-performance aramid paper production equipment, the aramid base paper prepared in S4 is hot-pressed by a double-layer or multi-layer composite process, the hot-pressing temperature is 220-290°C, the line pressure of the hot-pressing roller is 50-100kg / cm, and the roller speed is 0.5-2m / min;

[0029] When using double-layer composite technology, the paper weight is 115-125g / m 2 When the three-layer composite process is used, the paper weight is 70-80g / m 2 When the four-layer composite process is used, the paper weight is 55-60g / m 2 When the five-layer composite process is used, the paper weight is 44-50g / m 2 When the six-layer composite process is used, the paper weight is 38-41g / m 2 When using the seven-layer composite process, the paper weight is 31-35g / m 2 When the eight-layer composite process is used, the paper weight is 27-31g / m 2; It is preferred to use six-layer and eight-layer composite processes. When using the six-layer composite process, the paper sheets are composited into three different paper sheets by a pre-compounding method, i.e. two layers are pre-compounded into one paper sheet, followed by hot pressing composite; when using the eight-layer composite process, the paper sheets can be composited into three to four paper sheets, followed by hot pressing composite.

[0030] In the above technical solution, the technical effects and advantages provided by the present invention are:

[0031] 1. By using meta-aramid chopped fibers and meta-aramid fibrids as raw materials, and using surfactants to treat meta-aramid chopped fibers and meta-aramid fibrids to improve the bonding ability between fibers and pulp, and using pre-compounding and hot-compounding methods to use a multi-layer composite process for hot pressing, the multi-layer hot pressing process can improve the compactness of the paper sheet, and the heat treatment can make most of the meta-aramid melt, and under certain high temperature and high pressure conditions, the molecular weight arrangement is made denser. Under the combined effect of these factors, the electrical insulation strength of aramid paper is greatly improved;

[0032] 2. By arranging multiple rows of auxiliary extrusion rollers at the outer end of the main extrusion roller, each row of auxiliary extrusion rollers has multiple numbers, and each auxiliary extrusion roller independently cooperates with the main extrusion roller to perform hot pressing work. Even if the thickness of the aramid paper at the contact part of each auxiliary extrusion roller is different, the hot pressing work between the auxiliary extrusion rollers will not affect each other, avoiding poor composite effect caused by uneven thickness of aramid paper and improving the forming effect of aramid paper. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0034] Figure 1 It is the overall structure diagram of the production equipment of the present invention;

[0035] Figure 2 This is the internal structure diagram of the protective cover of the production equipment;

[0036] Figure 3 This is a top-down structural diagram of the protective cover of the production equipment;

[0037] Figure 4 This is the structural diagram of the protective cover and auxiliary extrusion roller of the production equipment;

[0038] Figure 5 This is the structural diagram of the auxiliary extrusion roller and pressure assembly of the production equipment;

[0039] Figure 6It is a cross-sectional view of the auxiliary extrusion roller and the pressure component of the production equipment;

[0040] Figure 7 This is the structural diagram of the main extrusion roller of the production equipment;

[0041] Figure 8 This is a cross-sectional view of the main extrusion roller of the production equipment.

[0042] Description of reference numerals:

[0043] 1. Main extrusion roller; 101. Main heating cylinder; 102. Sealing cover; 103. Hollow shaft; 2. Base; 3. Hydraulic cylinder; 4. Lifting rod; 5. Connecting plate; 6. Connecting arm; 7. Steam channel; 8. Protective cover; 9. Fixed seat; 10. Guide roller; 11. End plate; 12. Sealing cover; 13. External pipe; 14. Dust suction channel; 15. Dust suction groove;

[0044] 16. Pressure-applying assembly; 1601. Bracket; 1602. Telescopic rod; 1603. Spring; 1604. Hose; 1605. Closing cylinder; 17. Auxiliary extrusion roller; 1701. Auxiliary heat-conducting cylinder; 1702. End cover; 1703. Air duct. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0046] The present invention provides Figure 1-8 The production equipment of high-voltage resistant and high-performance aramid paper shown in the figure comprises a main squeezing roller 1, a protective cover 8 is provided above the main squeezing roller 1, a plurality of rows of auxiliary squeezing rollers 17 are provided inside the protective cover 8, and a plurality of auxiliary squeezing rollers 17 are provided in each row, the auxiliary squeezing rollers 17 are in contact with the outer end of the main squeezing roller 1, and a pressure component 16 is provided outside the auxiliary squeezing roller 17;

[0047] During the hot pressing process, the aramid paper moves and passes through the main squeezing roller 1, so as to continuously perform hot pressing. A plurality of rows of auxiliary squeezing rollers 17 are provided at the outer end of the main squeezing roller 1. During hot pressing, the aramid paper is sandwiched between the auxiliary squeezing roller 17 and the main squeezing roller 1. The movement of the aramid paper causes the main squeezing roller 1 and the auxiliary squeezing roller 17 to rotate, and the external force pushes the auxiliary squeezing roller 17 to apply pressure to the aramid paper. At the same time, high-temperature steam is used to heat the main squeezing roller 1 and the auxiliary squeezing roller 17, and then the aramid paper is heated to achieve hot pressing. The high temperature melts the fibers in the aramid paper, and under the action of pressure, the multiple layers of aramid paper stacked together are bonded to each other, so as to form a composite.

[0048] In order to make the pressure uniform during hot pressing, Figure 3-6As shown, there is a gap between two adjacent auxiliary squeezing rollers 17 in the same row, and the distribution of the auxiliary squeezing rollers 17 in the two adjacent rows is staggered, wherein the gaps of the auxiliary squeezing rollers 17 in one row correspond to the gaps of the auxiliary squeezing rollers 17 in the other row, and the pressure component 16 includes a bracket 1601, and the auxiliary squeezing roller 17 is located inside the corresponding bracket 1601 and is rotatably connected to the inner wall of the bracket 1601;

[0049] Two telescopic rods 1602 and two springs 1603 are provided between the bracket 1601 and the inner wall of the protective cover 8. The two ends of the telescopic rod 1602 are respectively connected to the inner wall of the protective cover 8 and the bracket 1601, and the same is true for the spring 1603. The two springs 1603 are respectively sleeved on the outer ends of the two telescopic rods 1602. The springs 1603 are in a compressed state during the hot pressing process. The elastic force of the springs 1603 pushes the auxiliary extrusion roller 17, so that the auxiliary extrusion roller 17 applies pressure to the aramid paper.

[0050] Since there are multiple auxiliary squeezing rollers 17 in each row of auxiliary squeezing rollers 17, each auxiliary squeezing roller 17 independently cooperates with the main squeezing roller 1 to perform hot pressing work. Even if the thickness of the aramid paper at the contacting parts of each auxiliary squeezing roller 17 is different, the hot pressing work between the auxiliary squeezing rollers 17 will not affect each other, thereby avoiding poor composite effect caused by uneven thickness of the aramid paper and improving the forming effect of the aramid paper. Since there are gaps between adjacent auxiliary squeezing rollers 17 in the same row and the distribution of two adjacent rows of auxiliary squeezing rollers 17 is staggered, the aramid paper that is not hot pressed in the gap of one row of auxiliary squeezing rollers 17 will be hot pressed by the other adjacent row of auxiliary squeezing rollers 17. The hot pressing positions of the two adjacent rows of auxiliary squeezing rollers 17 are complementary and will not cause omissions.

[0051] The high temperature of hot pressing is provided by steam, such as Figure 2 , 3 As shown in Figures 5 and 6, the auxiliary extrusion roller 17 includes an auxiliary heat-conducting tube 1701 made of metal, and end covers 1702 are provided at both ends of the auxiliary heat-conducting tube 1701. The end cover 1702 is connected to the auxiliary heat-conducting tube 1701 through bolts, and an air guide tube 1703 is fixedly provided on the end cover 1702. One end of the air guide tube 1703 is communicated with the auxiliary heat-conducting tube 1701, and the air guide tube 1703 is movably connected to the bracket 1601 through a sealed bearing.

[0052] Both sides of the bracket 1601 are provided with closed cylinders 1605, and the other ends of the two air guide tubes 1703 are respectively connected to the two closed cylinders 1605, and a high temperature resistant hose 1604 is fixed on the top of the closed cylinder 1605;

[0053] The outer end of the protective cover 8 is fixedly provided with a plurality of steam channels 7 for circulating high-temperature steam, each steam channel 7 corresponds to a row of auxiliary extrusion rollers 17, one end of the hose 1604 is connected to the corresponding steam channel 7, both ends of the steam channel 7 are provided with detachable closing covers, and the closing covers are fixedly provided with pipes for conducting steam, and the high-temperature steam is input into the steam channel 7 through the pipe at one end and then discharged from the pipe at the other end.

[0054] High-temperature water vapor is input into the steam channel 7. The water vapor entering the steam channel 7 enters the auxiliary extrusion roller 17 through the hose 1604 and the sealing tube 1605. The outer end of the auxiliary heat-conducting tube 1701 is in direct contact with the aramid paper. The water vapor entering the auxiliary heat-conducting tube 1701 conducts heat to the aramid paper through the auxiliary heat-conducting tube 1701, thereby heating it.

[0055] The protective cover 8 is arranged on the outside of the main squeezing roller 1 to play a protective role, such as Figure 1 As shown, a base 2 is provided at the bottom of the main squeezing roller 1, and connecting plates 5 are fixed at the four corners of the protective cover 8. A lifting rod 4 is provided at the top of the connecting plate 5. The connecting plate 5 and the lifting rod 4 can be detached and separated, and a connecting arm 6 is provided at the top of the lifting rod 4;

[0056] A hydraulic cylinder 3 is provided on one side of the lifting rod 4, and the bottom end of the hydraulic cylinder 3 is connected to the top of the base 2. The piston rod of the hydraulic cylinder 3 and the lifting rod 4 are connected by a connecting arm 6. The two ends of the connecting arm 6 are respectively connected to the top of the lifting rod 4 and the top of the piston rod of the hydraulic cylinder 3. The extension and retraction of the hydraulic cylinder 3 can drive the lifting rod 4 and the connecting plate 5 and then drive the protective cover 8.

[0057] The extension and retraction of the hydraulic cylinder 3 can drive the lifting rod 4 and the connecting plate 5, and then drive the protective cover 8 to move up and down. During hot pressing, the hydraulic cylinder 3 pulls the protective cover 8 down and makes the auxiliary extrusion roller 17 fit tightly against the outer end of the main extrusion roller 1. If necessary, the protective cover 8 can also be pushed up by the hydraulic cylinder 3 to inspect and repair the main extrusion roller 1. During the hot pressing process, the protective cover 8 is wrapped around the outer end of the main extrusion roller 1, which can isolate the high-temperature auxiliary extrusion roller 17 and the main extrusion roller 1 from the outside world to avoid burns.

[0058] It is also necessary to input high temperature steam into the main squeeze roller 1, such as Figure 1 , 7As shown in , 8, two fixing seats 9 are fixedly provided at the top of the base 2, and the main extrusion roller 1 is located between the two fixing seats 9. The main extrusion roller 1 includes a main heating tube 101 made of metal, and detachable sealing covers 102 are provided at both ends of the main heating tube 101. Hollow shafts 103 are fixedly provided on the two sealing covers 102. The two hollow shafts 103 are rotatably connected to the two fixing seats 9 respectively, and the hollow shafts 103 pass through the fixing seats 9 and are movably connected to the fixing seats 9 through sealed bearings.

[0059] The two fixing seats 9 are each provided with a sealing cover 12 , and an external pipe 13 with a valve is fixedly provided at the bottom of the sealing cover 12 . The two hollow shafts 103 are respectively connected to the inside of the two sealing covers 12 , so as to input high-temperature steam into the main extrusion roller 1 .

[0060] High-temperature steam is input into the sealing cover 12 from one of the external pipes 13, and enters the main heating tube 101 through the sealing cover 12 and the hollow shaft 103, thereby heating the main heating tube 101 from the inside to the outside. The main heating tube 101 also heats the aramid paper. The steam after passing through the main heating tube 101 is discharged to the outside through the other sealing cover 12 and the external pipe 13.

[0061] During the hot pressing process, the surface of the main extrusion roller 1 must not be contaminated with dust or impurities. Figure 7 , 8 As shown, a dust suction channel 14 is fixedly provided at the top of the base 2, and the dust suction channel 14 is located between the two fixing seats 9. A negative pressure pipe is fixedly provided at the outer end of the dust suction channel 14, and a negative pressure pump is externally connected to the negative pressure pipe to extract the air in the dust suction channel 14. A dust suction groove 15 is opened at the top of the dust suction channel 14, and the dust suction groove 15 is located directly below the main squeezing roller 1;

[0062] Guide rollers 10 are provided on both sides of the main squeezing roller 1 , and both ends of the guide roller 10 are rotatably connected with end plates 11 , and the two end plates 11 are fixed on two fixing seats 9 respectively.

[0063] The air inside the dust suction channel 14 is extracted to make the inside negative pressure. Under the negative pressure state, the dust suction groove 15 generates suction. When the main squeezing roller 1 rotates and passes above the dust suction groove 15, the dust on the surface of the main squeezing roller 1 is sucked into the dust suction channel 14 under the action of suction, so as to clean its surface and prevent the dust from affecting the hot pressing. The guide rollers 10 on both sides of the main squeezing roller 1 play a guiding role, changing the moving direction of the aramid paper when it reaches and leaves the main squeezing roller 1. Before reaching the main squeezing roller 1, the horizontally moving aramid paper bypasses the bottom end of the guide roller 10 on the corresponding side, and then extends upward to the inside of the protective cover 8 and is sandwiched between the main squeezing roller 1 and the auxiliary squeezing roller 17 to obtain hot pressing. The hot-pressed aramid paper moves downward and bypasses the bottom end of the other guide roller 10, and is converted into horizontal movement again.

[0064] The present invention also includes a method for producing the high-voltage resistant high-performance aramid paper, and the specific steps are as follows:

[0065] S1: meta-aramid chopped fiber pretreatment;

[0066] S1.1: Meta-aramid short-cut fibers are prepared by neutralizing isophthaloyl chloride with meta-phenylenediamine as raw materials. During the preparation, isophthaloyl chloride is added dropwise to meta-phenylenediamine, and the mixture is stirred in a reactor. The mixture is reacted at -45°C for 30 minutes, and then an excess of organic solvent is added. The mixture is stirred to obtain a meta-aramid polymer solution. The mixture is then broken into a gel by a homogenizer, and finally deionized water is added and stirred to obtain a meta-aramid nanofiber solution. The solution is spun into long and thin fiber filaments by a spinning machine, and finally cut into 5 mm or 6 mm long meta-aramid short-cut fibers;

[0067] S1.2: Use anionic surfactant or a combination of anionic surfactant and neutral surfactant to soak the meta-aramid chopped fibers for pretreatment. Sodium dodecylbenzene sulfonate can be used as the anionic surfactant, and the compound surfactant can be a combination of sodium dodecylbenzene sulfonate and fatty alcohol polyoxyethylene ether. When using the above-mentioned ionic surfactants, the recommended concentration is 5E-4mol / L to 5E-3mol / L, the temperature is room temperature, the soaking time is 0.5h, and then washed and dried.

[0068] S2: meta-aramid fibrid pretreatment;

[0069] S2.1: using m-phenylenediamine and isophthaloyl chloride as raw materials to prepare meta-aramid fibrids, preparing a meta-aramid nanofiber solution in the same manner as in S1.1, and grinding the solution into fibrids by a disc mill;

[0070] S2.2: using anionic surfactant or a combination of anionic surfactant and neutral surfactant to soak meta-aramid fibrid for pretreatment, the treatment method is the same as that in S1.2, using meta-aramid chopped fibers and meta-aramid fibrid as raw materials to make aramid paper, and using surfactant to pretreat it, which greatly improves the bonding ability between fibers and helps to improve the electrical insulation ability of aramid paper;

[0071] S3: adding the meta-aramid chopped fibers treated by S1 into a fiber deflaker for deflaking, and then adding the meta-aramid fibrids treated by S2 for secondary deflaking to obtain a suspension, wherein the mass ratio of the meta-aramid chopped fibers to the fibrids during deflaking is 4:6 to 6:4, i.e., the proportion of the fibrids is 40% to 60%, and the speed of the deflaker is 10000 r / min-20000 r / min;

[0072] S4: The suspension obtained in S3 is transferred to a circular automatic paper former for dehydration and forming into aramid base paper. During the forming, a dispersant is added to the suspension for dispersion. The dispersant is polyethylene oxide, and the added amount is 0.05 to 0.05 of the mass of the meta-aramid chopped fiber and meta-aramid pulp system. The evenly dispersed suspension is added to the circular automatic paper former for dehydration and forming. A circular roller is used for dehydration and forming. The paper is placed in a vacuum dryer for dehydration at a pressure of 0.1 MPa and a temperature of 95°C. The paper is then demoulded and placed in a 90°C oven for drying for 2 hours, and the weight is measured. The paper is then placed back in the oven and the weight is measured every half an hour. When the difference between the two weights is less than 0.3 mg, the paper is taken out and sealed in a fresh-keeping bag to obtain the aramid base paper. The final weight of the aramid base paper is 25-150g / m 2 ;

[0073] S5: Using the above-mentioned high-voltage resistant and high-performance aramid paper production equipment, the aramid base paper prepared in S4 is hot-pressed by a double-layer or multi-layer composite process, the hot-pressing temperature is 220-290°C, the line pressure of the hot-pressing roller is 50-100kg / cm, and the roller speed is 0.5-2m / min;

[0074] When using double-layer composite technology, the paper weight is 115-125g / m 2 When the three-layer composite process is used, the paper weight is 70-80g / m 2 When the four-layer composite process is used, the paper weight is 55-60g / m 2 When the five-layer composite process is used, the paper weight is 44-50g / m 2 When the six-layer composite process is used, the paper weight is 38-41g / m 2 When the seven-layer composite process is used, the paper weight is 31-35g / m 2 When the eight-layer composite process is used, the paper weight is 27-31g / m 2 ; It is preferred to use six-layer and eight-layer composite processes. When the six-layer composite process is used, the paper sheets are composited into three different paper sheets by a pre-compounding method, that is, two layers are pre-compounded into one paper sheet, and then hot-pressed composite is performed; when the eight-layer composite process is used, the paper sheets can be composited into three to four paper sheets and then hot-pressed composite. The multi-layer hot-pressing process can increase the compactness of the paper sheets, and the heat treatment can cause most of the meta-aramid to melt, and under certain high temperature and high pressure conditions, the molecular weight arrangement is made denser, further improving the electrical insulation properties of the aramid paper.

[0075] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A production device for high voltage resistant and high performance aramid paper, comprising a main squeezing roller (1), characterized in that: A protective cover (8) is provided above the main squeezing roller (1), and a plurality of rows of auxiliary squeezing rollers (17) are provided inside the protective cover (8). There are a plurality of auxiliary squeezing rollers (17) in each row. The auxiliary squeezing rollers (17) are in contact with the outer ends of the main squeezing rollers (1), and a pressure component (16) is provided on the outer sides of the auxiliary squeezing rollers (17); There is a gap between two adjacent auxiliary squeezing rollers (17) in the same row, and the distribution of the auxiliary squeezing rollers (17) in two adjacent rows is staggered. The pressure component (16) includes a bracket (1601), and the auxiliary squeezing roller (17) is located inside the corresponding bracket (1601) and is rotatably connected to the inner wall of the bracket (1601); Two telescopic rods (1602) and two springs (1603) are provided between the bracket (1601) and the inner wall of the protective cover (8), and the two springs (1603) are respectively sleeved on the outer ends of the two telescopic rods (1602), and the springs (1603) are in a compressed state during the hot pressing process.

2. The production equipment of high voltage resistant high performance aramid paper according to claim 1, characterized in that: The auxiliary extrusion roller (17) comprises an auxiliary heat-conducting tube (1701) made of metal, both ends of the auxiliary heat-conducting tube (1701) are provided with end covers (1702), and an air guide tube (1703) is fixedly provided on the end cover (1702).

3. The production equipment of high voltage resistant high performance aramid paper according to claim 2, characterized in that: Both sides of the support (1601) are provided with a closed tube (1605), and a high temperature resistant hose (1604) is fixedly provided on the top of the closed tube (1605); The outer end of the protective cover (8) is fixedly provided with a plurality of steam channels (7) for circulating high-temperature steam, each steam channel (7) corresponds to a row of auxiliary extrusion rollers (17), and one end of the hose (1604) is connected to the corresponding steam channel (7).

4. The production equipment of high voltage resistant high performance aramid paper according to claim 1, characterized in that: The bottom of the main squeezing roller (1) is provided with a base (2), the four corners of the protective cover (8) are fixed with connecting plates (5), the top of the connecting plate (5) is provided with a lifting rod (4), and the top of the lifting rod (4) is provided with a connecting arm (6); A hydraulic cylinder (3) is provided on one side of the lifting rod (4), the bottom end of the hydraulic cylinder (3) is connected to the top end of the base (2), the piston rod of the hydraulic cylinder (3) and the lifting rod (4) are connected via a connecting arm (6), and the extension and retraction of the hydraulic cylinder (3) can drive the lifting rod (4) and the connecting plate (5) and further drive the protective cover (8).

5. The production equipment of high voltage resistant high performance aramid paper according to claim 4, characterized in that: Two fixing seats (9) are fixedly provided at the top of the base (2), the main extrusion roller (1) is located between the two fixing seats (9), the main extrusion roller (1) comprises a main heating tube (101) made of metal, both ends of the main heating tube (101) are provided with detachable sealing covers (102), the two sealing covers (102) are fixedly provided with hollow shafts (103), and the two hollow shafts (103) are respectively rotatably connected to the two fixing seats (9).

6. The production equipment of high voltage resistant high performance aramid paper according to claim 5, characterized in that: The two fixed seats (9) are each provided with a sealing cover (12), an external pipe (13) with a valve is fixedly provided at the bottom end of the sealing cover (12), and the two hollow shafts (103) are respectively communicated with the interior of the two sealing covers (12).

7. The production equipment of high voltage resistant high performance aramid paper according to claim 5, characterized in that: A dust suction channel (14) is fixedly provided at the top of the base (2), the dust suction channel (14) is located between the two fixed seats (9), a negative pressure pipe is fixedly provided at the outer end of the dust suction channel (14), a dust suction groove (15) is opened at the top of the dust suction channel (14), and the dust suction groove (15) is located directly below the main squeezing roller (1); Guide rollers (10) are provided on both sides of the main squeezing roller (1), and both ends of the guide roller (10) are rotatably connected to end plates (11), and the two end plates (11) are respectively fixed on two fixed seats (9).

8. A method for producing high voltage resistant high performance aramid paper, characterized in that: The specific steps are as follows: S1: meta-aramid chopped fiber pretreatment; S1.1: Meta-aramid chopped fibers are prepared by neutralizing isophthaloyl chloride with meta-phenylenediamine; S1.2: Pre-treating the meta-aramid chopped fibers by soaking them with an anionic surfactant or a combination of an anionic surfactant and a neutral surfactant; S2: meta-aramid fibrid pretreatment; S2.1: Using m-phenylenediamine and isophthaloyl chloride as raw materials to produce m-aramid fibrid; S2.2: Pre-treat the meta-aramid fibrid by soaking it with an anionic surfactant or a combination of an anionic surfactant and a neutral surfactant, in the same manner as in S1.2; S3: adding the meta-aramid chopped fibers treated by S1 into a fiber deflaker for deflaking, and then adding the meta-aramid fibrids treated by S2 for secondary deflaking to obtain a suspension; S4: transferring the suspension obtained in S3 to a circular automatic paper sheet former for dehydration to form aramid base paper; S5: Using the production equipment as described in any one of claims 1 to 7, the aramid base paper prepared in S4 is hot-pressed into a double-layer or multi-layer composite process.

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