Processing and production process for insulating rolled end ring of transformer

Abstract

The invention relates to a transformer part production technology, in particular to a transformer insulation rolled end ring processing production technology which comprises the steps of preorder preparation, end ring processing and packaging and box sealing. In the preorder preparation process, a proper end ring mold is selected according to the end ring inner diameter required by a drawing or a technical list, and the outer surface of the end ring mold is wrapped with kraft paper or a paperboard; the end ring machining process comprises the steps of end ring binding, circle rolling, drying, bonding, drying and machining. The method aims at technical guidance and quality requirements of the manufacturing process of the rolled open insulation inclined end ring and the rolled closed end ring which are bonded by the casein glue, and ensures that the product meets the design and use requirements of customers.

Description

Technical Field

[0001] The invention relates to a transformer component production technology, in particular to a transformer insulation rolled end ring processing and production process. Background Art

[0002] Transformer paper end rings are insulating components between the transformer coil end insulation and the iron yoke. They typically consist of paper rings and spacers. Their processing presents several challenges, primarily in terms of material properties, machining accuracy, and process complexity.

[0003] In the traditional glue-brushing process, the glue contains a large amount of water, which causes the insulating end rings of paper products to shrink significantly, affecting the dimensional accuracy; the end rings that are not brushed with glue have poor integrity and insufficient strength, and cannot meet the use requirements; the glue is not brushed evenly, and gaps are easily formed between the paper layers, resulting in unqualified products.

[0004] Therefore, there are many difficulties in the production process of transformer paper end rings. To this end, the present invention proposes a transformer insulation rolled end ring processing and production process to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a production process for processing transformer insulation rolled end rings to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions: A transformer insulation rolled end ring processing and production process comprises the following steps: Step 1: Preliminary preparation: select a suitable end ring mold according to the inner diameter of the end ring required by the drawing or technical list, and wrap the outer surface of the end ring mold with kraft paper or cardboard; Step 2: end ring processing, including tying the end rings, rounding, drying, bonding, drying, and processing; Step three: packaging and boxing.

[0007] The transformer insulation rolled end ring processing and production process as described above: Step 1, when applying the mold, select the end ring mold with the closest inner diameter to the product to make the product. In the case that the end ring mold is not straight enough, the outer diameter of the end ring mold can be padded with two layers of 5mm cardboard before tying the end ring; When the width dimension of the rolled end ring is composed, the thickness of the material is reduced by 1mm for every 20mm of width dimension according to the accumulation of the cardboard stacking and bonding thickness. The material composition of the rolled end ring includes the main material. The thickness of the main material is 3mm cardboard as the main material and 2mm cardboard as the adjustment basis. The end ring is arranged in the order of inner diameter to outer diameter according to the width size, cardboard thickness and composition method. Then cut the material, calculate according to the drawing dimensions and verify the list dimensions to ensure they are correct, and finally prepare the tools and process materials.

[0008] The transformer insulation rolled end ring processing and production process as described above: in the step 2, when tying the end ring, if the cutting size of the tied end ring exceeds the size of the cardboard raw material, the slope is planed and overlapped for bonding; the cutting processing line is drawn before processing the slope, and during the planing process, the slope is uniform and the size is accurate, and no bumps or steps are allowed; if the product diameter is small and difficult to tie, the center cardboard is humidified before rolling, and then heated after the humidification treatment. After heating, it is covered, and a film is covered between each layer of cardboard, and the film is folded up to cover the cardboard.

[0009] The transformer insulation rolled end ring processing and production process as described above: in the step 2, before rolling, confirm that the cardboard is not swollen, cracked, damaged, or stained after being sprayed with water. When rolling the cardboard, put one end of the insulating cardboard into the rolling machine, first roll it into a large circle, and gradually reduce it to the required diameter, rolling it back and forth 2-3 times; the roundness is kept uniform, and cracks, wrinkles, damage, and oil stains are not allowed; when rolling, avoid sagging the cardboard to prevent deformation; use arc starting plates at the groove and both ends for rounding as needed; for those with grooves, overlap the grooves, fix the sloped part with U-shaped clips with thick cardboard strips, and place the end rings upright.

[0010] The transformer insulation rolled end ring processing and production process as described above: in the step 2, during drying, the rounded cardboard is wrapped on the end ring mold, and then the cardboard is evenly tightened with a tightening belt, with the spacing between each tightening belt within 50 mm, and a 2 mm thick cardboard pad is placed on the inside of the tightening device to avoid damaging the cardboard surface; then the mold wrapped with the cardboard is sent to the oven for drying at a drying temperature of 105±5°C for 12-16 hours.

[0011] The transformer insulation rolled end ring processing and production process as described above: in the step 2, during bonding, binding and bonding begins after the veneer is dried. According to the product structure size, if the product size is larger than the size of the cardboard raw material, each layer of cardboard is first spliced ​​and bonded according to the technical list, and bonding is carried out using a paper tube bonding machine. When bonding, the splicing overlap line is marked, and the bonding overlap does not produce offset, ensuring that the arcs of the two spliced ​​sections of cardboard are coaxial after splicing and bonding; the splicing positions of each adjacent layer are staggered evenly in the circumferential direction, with a staggered distance of more than 600mm and a splicing section of more than 1500mm; and there is only one overlap at the same position. The cardboard after splicing and bonding has its overlap surface treated with thickness, and the deviation between the treated size and the original cardboard thickness size is within 0.5mm. The cardboard after the overlap surface treatment can be bound and bonded, and the cardboard without splicing can be directly bound and bonded.

[0012] The transformer insulation rolled end ring processing and production process as described above: during the binding process, the inner layer of cardboard is wrapped onto the end ring mold in sequence, and then the outer side cardboard is brushed with glue, and the middle layer of cardboard is fully glued on both sides; each layer of cardboard is brushed with glue and wrapped onto the end ring mold in sequence, and aligned with the inner layer of cardboard and the lower end; after the cardboard is molded, it is tightened in time from the middle from the upper and lower inner ends with a nylon tightening belt, and the open end ring tightening device is placed at the same end of the opening. When tightening, the extension direction of the cardboard is tightened in sequence with the tightening direction of the tightening belt, and a leather hammer is used to knock in the tightening direction of the tightening belt at the same time, so that excess glue and air in the product are discharged to the outside. There should be no gaps between the cardboard layers, the smaller the spacing between the tightening belts, the better, and the tightening force is uniform and consistent, to ensure that the end ring layers are tightly bonded without air holes and cracks.

[0013] The production process of transformer insulation rolled end rings as described above: closed end rings have one more overlap than open end rings, and glue is applied to the inside and outside of the cardboard overlap surface during binding. The overlap groove direction of each layer is consistent, and the overlap positions of the outer cardboards of adjacent layers are evenly staggered according to the number of layers of end rings. During the binding process, the tightening belt is used for pre-tightening every two layers, and the upper and lower overlap positions are clamped with a G-shaped clamp, and then the glue is applied to the next layer of cardboard for binding. The G-shaped clamp of the previous layer is released during binding. When tightening each layer of tightening belt, the tightening device needs to avoid the overlap surface of the groove. Among them, for products tightened with a tightening belt, the tightening device must be placed at the starting position on the same side where the product can be tightened and extended by the tightening belt.

[0014] The transformer insulation rolled end ring processing and production process as described above: in the step 2, when drying, the end ring is sent into the drying oven in a tightened state for drying at a temperature of 105±5°C for 12-14 hours, and is taken out and laid flat after the temperature in the oven drops to room temperature.

[0015] The above-mentioned transformer insulation rolled end ring processing and production process: in the step 2, during processing, after drying, naturally cool to below 50°C, remove the tightening belt and demould, take the cable paper and unfold it according to the size and length, and cut it into a predetermined shape, then compound the cable paper pattern on the end ring tube and mark it, after checking the pattern, saw the upper and lower ends and the bevel of the end ring tube, remove the burrs at the overlap, and use a manual electric planer to flatten it, and process it to the predetermined shape to make it smooth and without sharp corners and burrs; if a support bar is added in the middle of the two end ring tubes, first measure the outer diameter unfolding size of the two end ring tubes respectively, and calculate the two hard end rings. The diameter spacing and the thickness of the stay are matched according to the diameter spacing of the end rings, and the thickness of the stays are adjusted with positive tolerance. Then, the two end rings are put together, and an equidistant line is drawn on the inner end ring tube. The stays are glued to the middle of the end rings with glue, aligned with the equidistant line, and so on. Finally, if the stays are found to be loose, the thickness is processed and then pasted. The stays are clamped with a clamping device while being glued to ensure that the stays fit tightly with the end rings. If insulated rivets are required to be used for fixing, holes must be drilled according to the requirements of the drawing, and the holes must be kept clean and free of carbonization. The insulated rivets are then used to fix them. After fitting, all insulating rivets must be flush with the surface of the end rings.

[0016] Compared with the prior art, the present invention has the following beneficial effects: the present invention provides technical guidance and quality requirements for the production process of rolled open insulating bevel end rings and rolled closed end rings bonded with casein glue, ensuring that the products meet customer design and usage requirements. DETAILED DESCRIPTION

[0017] The technical solutions of the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0018] As an embodiment of the present invention, the transformer insulation rolled end ring processing production process includes the following steps: Step 1: Preliminary preparation: Select a suitable end ring mold based on the inner diameter of the end ring required by the drawing or technical list, and wrap the outer surface of the end ring mold with kraft paper or cardboard. When applying the mold, give priority to using the end ring mold with the inner diameter closest to the product. If the end ring mold is not straight enough, the outer diameter of the end ring mold can be padded with two layers of 5mm cardboard before tying the end ring; When the width dimension of the rolled end ring is composed, the thickness of the material is reduced by 1mm for every 20mm of width dimension according to the accumulation of the cardboard stacking and bonding thickness. The material composition of the rolled end ring includes the main material. The thickness of the main material is 3mm cardboard as the main material and 2mm cardboard as the adjustment basis. The end ring is arranged in the order of inner diameter to outer diameter according to the width size, cardboard thickness and composition method. Then cut the material, calculate according to the drawing dimensions and verify the list dimensions to ensure they are correct, and finally prepare the tools and process materials.

[0019] Step 2: end ring processing, including tying the end rings, rounding, drying, bonding, drying, and processing; When tying the end rings, if the size of the tied end rings (including open and closed end rings) exceeds the size of the original cardboard material, the slopes should be planed and overlapped for bonding; before processing the bevel, the cutting line should be drawn. During the planing process, the slope should be uniform and the size should be accurate. Defects such as bumps and steps are not allowed. If the product diameter is small and difficult to tie, the center cardboard should be humidified before rounding, and then heated. After heating, cover the cardboard with film between each layer of cardboard, and fold the film up to cover the cardboard. Before rolling, make sure that the cardboard is not swollen, cracked, damaged, or stained after being sprayed with water. When rolling, place one end of the insulating cardboard into the rolling machine, first roll it into a large circle, and then gradually reduce it to the required diameter, rolling it back and forth 2-3 times; the roundness should be kept uniform, and no cracks, wrinkles, damage, or oil stains are allowed; it should be noted that when rolling, the cardboard should not sag to prevent deformation. In addition, arc starting plates should be used for rounding at the groove and both ends as needed; for those with grooves, overlap them according to the groove, fix the slope with a U-shaped clamp with thick cardboard strips, and place the end ring upright; During drying, wrap the rounded cardboard on the end ring mold, and then tighten the cardboard evenly with a tightening belt. The spacing between each tightening belt should not exceed 50mm. A 2mm thick cardboard pad should be placed inside the tightening device to avoid damaging the cardboard surface. Then, put the wrapped cardboard mold into the drying oven for drying at a temperature of 105±5℃ for 12-16 hours. During bonding, binding and bonding begin after the veneer is dried. According to the product structure size, if the product size is larger than the size of the cardboard raw material, each layer of cardboard should be spliced ​​and bonded according to the technical list. The bonding should be done with a paper tube bonding machine. When bonding, the splicing overlap line should be marked. The bonding overlap should not be offset to ensure that the arcs of the two spliced ​​sections of cardboard are coaxial after splicing and bonding. At the same time, in order to avoid the accumulation of thickness errors of the end rings during the later binding process, the adjacent splicing positions of each layer are required to be staggered evenly in the circumferential direction, with a stagger of at least 600mm. The splicing section should exceed 1500mm, and no more than two overlaps are allowed at the same position. After splicing and bonding, the cardboards are subjected to thickness treatment on the overlapping surfaces. The deviation between the treated dimensions and the thickness dimensions of the original cardboards shall not exceed 0.5mm. The cardboards after the overlapping surface treatment can be tied and bonded, and the cardboards that do not need to be spliced ​​can be tied and bonded directly. During the binding process, the inner cardboard is wrapped onto the end circle mold in sequence, and then the outer side cardboard is brushed with glue, and the middle cardboard is fully glued on both sides. After brushing glue on each layer of cardboard, it is wrapped onto the end circle mold in turn, and aligned with the upper and lower ends of the inner cardboard. After the cardboard is molded, it is tightened in time from the middle to the upper and lower inner ends with a nylon tightening belt. The tightening device of the open end circle is placed at the same end of the opening. The extension of the cardboard during tightening The stretching direction is tightened in sequence with the tightening direction of the tightening belt, and a leather hammer is used to knock in the tightening direction of the tightening belt to discharge the excess glue and air in the product outward. There should be no gap between the cardboard layers, the smaller the spacing between the tightening belts, the better, and the tightening force is uniform and consistent, ensuring that the end ring layers are tightly bonded without air holes and cracks; finally, the end ring is closed, and the closed end ring has one more overlap than the open end ring. When binding, glue is applied to the inside and outside of the cardboard overlap surface, and the overlap groove direction of each layer is consistent. At the same time, the overlap positions of the outer cardboards of adjacent layers are evenly staggered according to the number of layers of the end rings. During the binding process, the tightening belt is used to pre-tighten once every two layers. 1. When tightening each layer of the tightening belt, the tightening device must avoid the overlapping surface of the groove to prevent the tightening device from holding up the paper and making it impossible for the cardboard to extend in the tightening direction of the tightening belt. This will prevent the layers from being squeezed and not tightened properly when tightening multiple layers at the same time, resulting in quality risks such as dimensional deviation and cracking between layers. The rest of the binding methods are consistent with the open end ring. For products tightened with tightening belts, the tightening devices must be placed at the starting position on the same side where the product can be tightened and extended by the tightening belt. When drying, put it into the drying oven in a tightened state, the drying temperature is 105±5℃, the time is 12-14 hours, and after the temperature in the oven drops to room temperature, take it out and lay it flat; During processing, after drying, cool naturally to below 50℃, remove the tightening belt and demould, take the cable paper and unfold it according to the size and length, and cut it into the predetermined shape, then composite the cable paper pattern on the end ring tube and mark it. After checking the pattern, use a woodworking circular saw or a woodworking hand saw to cut the upper and lower ends and the bevel of the end ring tube, remove the burrs at the overlap, and use a manual electric planer to flatten it, and process it to the shape of the drawing to make it smooth and without sharp corners and burrs; if a stay is added between the two end ring tubes, first measure the outer diameter expansion size of the two end ring tubes respectively, calculate the diameter spacing between the two hard end ring tubes, and the thickness of the stay is based on The end ring diameter spacing is matched now, and the thickness of the stay is within the positive tolerance. Then, put the two end rings together, mark the bisecting line on the inner end ring tube as required, glue the stay in the middle of the end ring with glue, align with the bisecting line and glue, and so on. Finally, if the stay is found to be loose, it can be adjusted in thickness before pasting. Clamp it with a clamping device while pasting to ensure that the stay fits tightly with the end ring. If the drawing requires fixing with insulating rivets, drill holes according to the drawing requirements. The holes must be kept clean and free of carbonization. Then fix them with insulating rivets. After fitting, all insulating rivets must be flush with the surface of the end ring. Step three: packaging and boxing.

[0020] Additional points to note are: 1) Check the cardboard before binding to ensure it is clean.

[0021] 2) The binding process must control the cleanliness of the product. When brushing glue on the inner layer of the cardboard, a layer of clean plastic film or kraft paper should be placed on the bottom to prevent contamination of the cardboard.

[0022] 3) Place a 1.5 or 2mm cardboard under the tightening belt to prevent the tightening belt from damaging the product.

[0023] 4) The customer provides technical specifications and inspection specifications and the operation is carried out according to the customer's requirements.

[0024] The above embodiments are exemplary rather than restrictive, so any technical solution that can be implemented in other specific forms without departing from the spirit or basic features of the present invention is included in the present invention.

Claims

1. A transformer insulation winding end ring processing and production process, characterized in that: The steps include: Step 1: Preliminary preparation: select a suitable end ring mold according to the inner diameter of the end ring required by the drawing or technical list, and wrap the outer surface of the end ring mold with kraft paper or cardboard; Step 2: end ring processing, including tying the end rings, rounding, drying, bonding, drying, and processing; Step three: packaging and boxing.

2. The transformer insulation rolled end ring processing and production process according to claim 1 is characterized in that: In the first step, when applying the mold, the end ring mold with the closest inner diameter to the product is selected to make the product. In the case that the end ring mold is not straight enough, the outer diameter of the end ring mold can be padded with two layers of 5mm cardboard at most and then the end ring is tied; When the width dimension of the rolled end ring is composed, the thickness of the material is reduced by 1mm for every 20mm of width dimension according to the accumulation of the cardboard stacking and bonding thickness. The material composition of the rolled end ring includes the main material. The thickness of the main material is 3mm cardboard as the main material and 2mm cardboard as the adjustment basis. The end ring is arranged in the order of inner diameter to outer diameter according to the width size, cardboard thickness and composition method. Then cut the material, calculate according to the drawing dimensions and verify the list dimensions to ensure they are correct, and finally prepare the tools and process materials.

3. The transformer insulation rolled end ring processing and production process according to claim 1 is characterized in that: In the second step, when tying the end rings, if the blanking size of the tying end rings exceeds the size of the cardboard raw material, the slopes are planed and overlapped for bonding; before processing the slopes, the cutting lines are drawn, and during the planing process, the slopes are uniform and the sizes are accurate, and no bumps or steps are allowed; if the product diameter is small and difficult to tie, the center cardboard is humidified before rounding, and then heated after the humidification treatment. After heating, the cardboard is covered, and a film is covered between each layer of cardboard, and the film is folded up to cover the cardboard.

4. The transformer insulation rolled end ring processing and production process according to claim 3 is characterized in that: In the second step, before rolling, it is confirmed that the cardboard has no swelling, cracking, damage or stains after being sprayed with water. When rolling the cardboard, one end of the insulating cardboard is placed in a rolling machine, first rolled into a large circle, and then gradually reduced to the required diameter, and rolled back and forth 2-3 times; the roundness is kept uniform, and cracks, wrinkles, damage and oil stains are not allowed; when rolling, the cardboard is prevented from sagging to prevent deformation; the bevel and both ends are rolled with arc starting plates as needed; for those with bevels, the bevels are overlapped, and the sloped part is fixed with a U-shaped clamp using thick cardboard strips, and the end rings are placed upright.

5. The transformer insulation rolled end ring processing and production process according to claim 4 is characterized in that: In the second step, during drying, the rounded cardboard is wrapped on the end ring mold, and then the cardboard is evenly tightened with a tightening belt, with the spacing between each tightening belt within 50 mm, and a 2 mm thick cardboard pad is placed on the inside of the tightening device to avoid damaging the cardboard surface; then, the mold wrapped with the cardboard is sent to the oven for drying at a temperature of 105±5°C for 12-16 hours.

6. The transformer insulation rolled end ring processing and production process according to claim 1 is characterized in that: In the second step, during bonding, binding and bonding begins after the veneer is dried. According to the product structure size, if the product size is larger than the size of the cardboard raw material, each layer of cardboard is first spliced ​​and bonded according to the technical list, and bonding is carried out using a paper tube bonding machine. During bonding, the splicing overlap line is marked, and the bonding overlap does not produce offset, ensuring that the arcs of the two spliced ​​cardboard sections are coaxial after splicing and bonding; the splicing positions of each adjacent layer are staggered evenly in the circumferential direction, with a staggered distance of more than 600 mm and a splicing section of more than 1500 mm; and there is only one overlap at the same position. After splicing and bonding, the cardboard has its overlap surface treated for thickness, and the deviation between the treated size and the original cardboard thickness size is within 0.5 mm. The cardboard after the overlap surface treatment is completed can be bound and bonded, and cardboard without splicing can be directly bound and bonded.

7. The transformer insulation rolled end ring processing and production process according to claim 6, characterized in that: During the binding process, wrap the inner layer of cardboard onto the end circle mold in sequence, then brush glue on the outer side cardboard, and glue both sides of the middle layer of cardboard; after brushing glue, wrap each layer of cardboard onto the end circle mold in turn, and align it with the upper and lower ends of the inner layer of cardboard; after the cardboard is molded, use a nylon tightening belt to tighten it from the middle from the upper and lower inner ends in time, and place the open end circle tightening device at the same end of the opening. When tightening, the extension direction of the cardboard is tightened in sequence with the tightening direction of the tightening belt. At the same time, use a leather hammer to knock in the tightening direction of the tightening belt, so as to discharge the excess glue and air in the product. There should be no gaps between the cardboard layers. The smaller the spacing between the tightening belts, the better, and the tightening force is uniform and consistent to ensure that the end circle layers are tightly bonded without air holes or cracks.

8. The transformer insulation rolled end ring processing and production process according to claim 7, characterized in that: The closed end ring has one more overlap than the open end ring. When binding, glue is applied on the inside and outside of the cardboard overlap surface. The overlap groove direction of each layer is consistent. The overlap positions of the outer cardboards of adjacent layers are evenly staggered according to the number of layers of the end ring. During the binding process, the tightening belt is used to pre-tighten every two layers, and the upper and lower overlap positions are clamped with G-shaped clamps, and then the glue is applied to the next layer of cardboard for binding. The G-shaped clamp of the previous layer is released during binding. When tightening each layer of tightening belt, the tightening device needs to avoid the overlap surface of the groove. Among them, for products tightened with tightening belts, the tightening device must be placed at the starting position on the same side where the product can be tightened and extended by the tightening belt.

9. The transformer insulation rolled end ring processing and production process according to claim 1, characterized in that: In the step 2, during drying, the product is put into an oven in a tightened state for drying at a temperature of 105±5°C for 12-14 hours, and is taken out and laid flat after the temperature in the oven drops to room temperature.

10. The transformer insulation rolled end ring processing and production process according to claim 1, characterized in that: In the step 2, during processing, after drying, it is naturally cooled to below 50°C, the tightening belt is removed and demoulding is carried out, the cable paper is unfolded according to the size and length is laid out, and it is cut into a predetermined shape, and then the cable paper pattern is compounded on the end ring tube and marked. After checking the pattern, the upper and lower ends and the inclined surface of the end ring tube are sawed, the burrs are removed from the overlap, and a manual electric planer is used to flatten it, and it is processed into a predetermined shape to make it smooth and without sharp corners and burrs; if a support bar is added between the two end ring tubes, the outer diameter unfolding size of the two end ring tubes is measured respectively, and the diameter spacing between the two hard end ring tubes is calculated. The thickness of the support bar is based on the According to the end ring diameter spacing, the thickness of the support strip is adjusted to a positive tolerance. Then, the two end rings are simply put together, and an equidistant line is drawn on the inner end ring tube. The support strip is glued to the middle of the end ring with glue, aligned with the equidistant line and glued, and so on. Finally, if the support strip is found to be loose, it is processed to make it thinner and then pasted. While pasting, it is clamped with a clamping device to ensure that the support strip fits tightly with the end ring. If it is required to be fixed with insulating rivets, drill holes according to the requirements of the drawing, and the holes must be kept clean and free of carbonization. Then fix it with insulating rivets. After fitting, all insulating rivets must be flush with the surface of the end ring.