A method for positioning a central column and a mold

Abstract

This invention belongs to the technical field of transformer core column stacking, and particularly relates to a column positioning method and mold, comprising: S1: preparing stacking tools; S2: placing the column positioning mold with the upper yoke of the core as the positioning reference, adjusting it symmetrically and evenly left and right, front and back, and starting to stack the column; S3: preparing four suitable electrical laminates, one each for the front and back of the upper and lower clamps and on both sides, stacking the silicon steel sheets of the core, using the stacked column as the reference, first inserting and stacking the upper and lower yoke sheets, and using the corner hammers to flatten the pads until the entire core is stacked. This invention can solve the problem of poor yield rate in existing transformer core column positioning methods.

Description

Technical Field

[0001] This invention belongs to the technical field of transformer core column stacking technology, and particularly relates to a column positioning method and mold. Background Technology

[0002] The core of a transformer is the main magnetic circuit part of the transformer. It is usually made of hot-rolled or cold-rolled silicon steel with high silicon content and coated with insulating varnish. The core and the coils wound on it form a complete electromagnetic induction system.

[0003] Transformers can be classified into oil-immersed transformers and dry-type transformers according to their insulation and cooling systems. The existing manufacturing process for oil-immersed transformers is as follows: 1. Wind the low-voltage coil using electromagnetic wire or copper foil according to technical requirements, and then wind the required high-voltage coil outside the low-voltage coil; 2. Shape and dry the wound high- and low-voltage coils; 3. Assemble the dried high- and low-voltage coils with the fabricated core; 4. Dry the assembled core; 5. Assemble the dried core and place it in the pre-fabricated oil tank; 6. Vacuum fill the oil tank containing the core with oil at a vacuum level of approximately 2000 Pa and an oil temperature of room temperature; 7. Pressurize and allow to stand; 8. Finally, conduct a test. However, during the core stacking process of existing transformers, improper operation by operators can easily lead to significant bending, deformation, loosening, and skewness of the core, failing to meet tolerance and quality requirements and reducing the yield rate. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a method and mold for positioning the core of a transformer, so as to solve the problem of poor yield in the existing positioning of the core of a transformer.

[0005] The basic solution provided by this invention is a method for positioning a central column, comprising:

[0006] S1: Preparing stacking tools;

[0007] S2: Place the central column positioning mold with the iron yoke on the iron core as the positioning reference. Adjust it to be symmetrical and uniform in the left and right and front and back. Start stacking the central columns.

[0008] S3: Prepare four suitable electrical laminates, one each for the front and back of the upper and lower clamps and on both sides. Stack the silicon steel sheets for the iron core. Using the stacked central column as a reference, first insert the upper and lower iron yoke sheets, and use the corner hammer to flatten the pads until the entire iron core is stacked.

[0009] The principle and advantages of this invention are as follows: In this application, before stacking the middle column plates, the stacking tools are prepared. After preparation, the middle column positioning mold is placed according to the iron yoke on the transformer core as the reference. The use of the middle column positioning mold can ensure that the middle column plates are placed in the preset placement method. Then the middle column is stacked. After stacking, positioning is required. Pressure plates and iron yoke plates are used for fixing so that the stacking of the middle column plates meets the process design requirements.

[0010] The advantage of this application is that the stacking process is simple. With the assistance of the central column positioning mold, the possibility of stacking errors is reduced. At the same time, the iron yoke plate and pressure plate are used for fixation, making the stacked central column easy to transfer.

[0011] Furthermore, S1 includes:

[0012] S1-1: Arrange the central column plates in order from the smallest to the largest level, and wipe and clean the upper clamp, lower clamp, and auxiliary clamp of the iron core. According to the preset drawing, place the channel steel on the stacking platform, and place the upper and lower clamps on the channel steel in parallel according to the preset clamp spacing size. At the same time, place the auxiliary clamp and iron plate on the upper and lower clamps at the same level, and place the insulating part on the upper and lower clamps. The insulating part includes an edge part and a middle part. The edge part is rectangular and placed on the upper and lower clamps. The middle part is strip-shaped and its two ends are placed on the edge part of the upper and lower clamps.

[0013] S1-2: Place the smallest level central column piece in the middle part at one end of the upper clamping piece, and place it above the upper clamping piece using the central column positioning mold so that it matches the smallest level central column piece.

[0014] Furthermore, S2 includes:

[0015] S2-1: Start stacking the center column pieces from the smallest level center column. When stacking, stack them in sequence from the smallest level center column to the largest level center column according to the stacking part inside the center column positioning mold. During the stacking process, the gaps of the center columns at each level are aligned.

[0016] S2-2: Measure the edge distance of the center column at each level;

[0017] S2-3: The stacked central column is pressed onto the top using a pad.

[0018] Furthermore, S3 includes:

[0019] S3-1: Using the stacked central column as a reference, insert iron yoke plates and side column plates; the iron yoke plates are provided with V-shaped openings and bevels, the V-shaped openings match the sharp corners of the central column, and the bevels of the side column plates match the bevels of the iron yoke plates;

[0020] S3-2: Use flattening pads to flatten the stacked yoke plates and side posts.

[0021] A central column positioning mold includes a positioning piece, the positioning piece being V-shaped, with multiple protrusions at the included angle of the V-shape, and gaps between the protrusions.

[0022] Furthermore, the positioning plate is made of silicon steel. Attached Figure Description

[0023] Figure 1 This is a flowchart of an embodiment of the present invention;

[0024] Figure 2 This is a diagram showing the arrangement of the column plates during preparation in an embodiment of the present invention.

[0025] Figure 3 This is a schematic diagram of the central column positioning mold in an embodiment of the present invention;

[0026] Figure 4 This is a diagram showing the arrangement of the stacked central column pieces in an embodiment of the present invention. Detailed Implementation

[0027] The following detailed description illustrates the specific implementation method:

[0028] Implementation, for example Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, a method for positioning a center column includes:

[0029] S1: Preparatory stacking tool; wherein, S1 includes:

[0030] S1-1: Arrange the central column plates in order from the smallest to the largest level, and wipe and clean the upper clamp, lower clamp, and auxiliary clamp of the iron core. According to the preset drawing, place the channel steel on the stacking platform, and place the upper and lower clamps on the channel steel in parallel according to the preset clamp spacing size. At the same time, place the auxiliary clamp and iron plate on the upper and lower clamps at the same level, and place the insulating part on the upper and lower clamps. The insulating part includes an edge part and a middle part. The edge part is rectangular and placed on the upper and lower clamps. The middle part is strip-shaped and its two ends are placed on the edge part of the upper and lower clamps.

[0031] S1-2: Place the smallest level central column piece in the middle part at one end of the upper clamping piece, and place it above the upper clamping piece using the central column positioning mold so that it matches the smallest level central column piece.

[0032] In this embodiment, the equipment, tools, gauges, and materials for transformer stacking include:

[0033] Equipment: 5t overhead crane, 10t overhead crane, stacking table;

[0034] Tools: wooden hammer, mallet, flattening pad, soft steel wire lifting tool, nylon slings, various material trays, various wrenches, and binding straps;

[0035] Tooling: center column positioning mold, corner flattening pad, silicon steel sheet stacking plate, clamp, suitable (thickness 10-20mm) wooden board;

[0036] Measuring tools: 0-25mm micrometer, 45° square, 0-300mm steel ruler, 0-500mm vernier caliper, 0-1000mm vernier caliper, feeler gauge, 2m measuring tape, right angle ruler, spirit level;

[0037] Materials: Cold-rolled silicon steel sheets, clamps, screws, foot insulation, phenolic paper tubes, two-component polyurethane paint, etc., and binding straps.

[0038] In the process preparation work, firstly, familiarize yourself with the drawings and check whether the shearing dimensions of each level of silicon steel sheets and the dimensions of clamps, yoke insulation, screws, etc., conform to the specifications in the drawings. Then, perform material sorting. According to the design dimensions of the iron core drawings, count the silicon steel sheets of the central column from the small level to the main level in order from right to left. The stacking thickness of the main level is guaranteed by actual measurement according to the thickness in the drawings. The stacking thickness of the graded layers is stacked according to the number of sheets in the drawings. Next, clean the clamps. Wipe the upper and lower clamps, clamping screws, and tensioning screws on the high and low voltage sides of the iron core (alcohol can be used if necessary) to ensure the cleanliness of the clamps, clamping screws, and tensioning screws. Finally, use a vacuum cleaner to vacuum the stacking table to ensure that the stacking table is clean.

[0039] Next, the clamps are placed. According to the core drawing dimensions, suitable channel steel is used and placed on the stacking table. The spacing between the channel steel on the stacking table is adjusted, and the upper and lower clamps on the high-voltage side are placed parallel to each other on the channel steel. The dimensions between the upper and lower clamps and the diagonal dimensions are adjusted. Simultaneously, the matching auxiliary clamps, iron plates, and clamps must be leveled together and adjusted to the same horizontal plane, using a spirit level for measurement and correction. Then, the clamp insulation is placed, ensuring it is placed in the center of the clamps, symmetrically on both sides. For cores requiring binding of the core column, slotted auxiliary fixtures are also needed to facilitate binding after the core stacking is completed.

[0040] As shown in the figure, the final step is to place the center column positioning mold, and place the smallest-level center column piece in the middle of the small cardboard (usually, the smallest-level yoke piece should be placed in the center as a reference when the lower clamp is stacked). Then, place the center column positioning mold on the upper clamp, which must match the smallest-level center column without any gaps (for stacked dry-type transformer cores, it should be placed in the center of the pull plate).

[0041] S2: Using the iron yoke on the iron core as the positioning reference, place the center column positioning fixture, ensuring symmetry and uniformity in the left-right and front-back directions, and begin stacking the center columns; S2 includes:

[0042] S2-1: Start stacking the center column pieces from the smallest level center column. When stacking, stack them in sequence from the smallest level center column to the largest level center column according to the stacking part inside the center column positioning mold. During the stacking process, the gaps of the center columns at each level are aligned.

[0043] S2-2: Measure the edge distance of the center column at each level;

[0044] S2-3: The stacked central column is pressed onto the top using a pad.

[0045] In this embodiment, when stacking from the smallest level to the shortest central column, the distance between the upper and lower levels of the central column needs to be properly aligned (the distance between the upper and lower levels must be consistent, and the left and right sides must be symmetrical, without deviation from the center). Then, begin stacking central columns longer than the next level, aligning the gaps of the next level's central columns with the gaps of the previous level's large and small deviations (aligning the large and small deviations of the previous level's gaps with the large and small deviations of the next level's gaps), until the main level of central columns is stacked. Measure the thickness of the main level of central columns with calipers; it should match the drawing, and the thickness tolerance is allowed to be 0 to +2mm. Then, stack the remaining upper half of the central columns in sequence (adjusting the upper half of the central columns as needed, using the same method as before). After stacking all the central columns, use calipers to check whether the total thickness dimension matches the drawing requirements and whether the tolerance meets the process requirements.

[0046] Specifically: When stacking each level of central pillar, use flattening blocks to ensure flatness, so that the sharp corners of the central pillar sheet align with the central pillar positioning mold before pulling (adjusting). During stacking, pay attention to measuring the edge distances of the stage blocks, as shown in the diagram A, B, C, D…G, to ensure no stage block misalignment occurs and the diameter exceeds tolerance. For the thicknesses T1, T2, T3…T8 of each stage, although measured during sheet selection, strict measurement is still required for each stage during stacking. After stacking the widest stage (main stage), each subsequent stage gradually narrows, making it easy to visually determine if there is any stage block misalignment. The stacked central pillars can be temporarily held down with blocks to prevent the upper smaller stages from shifting. Remove the central pillar positioning mold.

[0047] S3: Prepare four suitable electrical laminates, one each for the front and back of the upper and lower clamps and on both sides. Stack the silicon steel sheets for the iron core. Using the stacked central column as a reference, first insert the upper and lower iron yoke sheets, and use the corner hammer to flatten the pads until the entire iron core is stacked.

[0048] S3 includes:

[0049] S3-1: Using the stacked central column as a reference, insert iron yoke plates and side column plates; the iron yoke plates are provided with V-shaped openings and bevels, the V-shaped openings match the sharp corners of the central column, and the bevels of the side column plates match the bevels of the iron yoke plates;

[0050] S3-2: Use flattening pads to flatten the stacked yoke plates and side posts.

[0051] In this embodiment, using the stacked central column as a reference, the upper and lower yoke plates are first inserted. Starting from the smallest level, the "V" opening of the yoke plate must align with the tip of the central column at each step. Then, the side column plates are placed, and the 45° angle between the side column and the yoke plate must align without any gaps. The alignment of the first level of stacked plates (the narrowest level) is crucial, as it determines the correctness of the subsequent stacking dimensions. Therefore, after stacking the small level, the distance between the two ends of the clamp and the small level side column must be measured with a ruler to adjust the left-right symmetry. The upper and lower yoke plates are then tapped tightly towards the central column using corner shims and a small hammer. Next, the corner shims are used to align the iron core protrusions (upper and lower yoke plates, and the protrusions of the two side columns) until they align. Then, the side columns and yoke plates are gently tapped outwards and then inwards with flattening shims until they are flat. Finally, the protrusions are carefully checked to ensure there are no overlaps; only after these checks are completed can the next level of plates be stacked.

[0052] When using the corner-tapping and flattening pad: it must be held vertically, perpendicular to the end face, and must not be used at an angle;

[0053] After stacking the main stage according to the above steps, the thickness needs to be checked. The thickness tolerance is 0 to +2mm. If the thickness is due to material reasons, it needs to be adjusted to be consistent with the center column. At the same time, self-inspect the verticality and horizontality of the main stage: the inner end face of the lower yoke must be flat and horizontal, and the outer face of the upper yoke must be flat and horizontal. After the self-inspection is qualified, stack the upper half stage in sequence until it is completed.

[0054] After the entire iron core is stacked, the total thickness and levelness must be measured according to the drawings. Check whether the joints, overlaps, diagonals, etc. meet the requirements. Only after the product is qualified can it be clamped, tightened, tied, and the pads and pad insulation erected.

[0055] As you stack and tidy, use flattening blocks to seal the seams and corner blocks to correct any protrusions in the iron core. Use calipers to check the stack thickness and a right-angle ruler to check the verticality, continuing until the stacking is complete.

[0056] When stacking 10mm or each grade of lamination less than 16mm, gently tap the core laminations with a flattening block to align them, reduce joint gaps, and eliminate unevenness at overlaps and end faces. Gaps and unevenness must meet technical specifications; generally, the maximum gap should be ≤1mm and the unevenness ≤1mm. During the stacking process, frequent repairs, tapping, measurements, and inspections are essential to prevent mis-stacking, excessive overlaps, and joint defects. For oil-fired transformers, transformer oil can be used as a lubricant. Apply a coating to the sharp corners of the core column during lamination to facilitate the insertion of the upper and lower yoke laminations.

[0057] like Figure 3 As shown, in other embodiments of this embodiment, a central column positioning mold is also included, including a positioning piece. The positioning piece is V-shaped, and multiple protrusions are provided at the included angle of the V-shape of the positioning piece. There are gaps between the protrusions, and the gaps formed by adjacent protrusions can accommodate the central column pieces for stacking. The positioning piece is made of silicon steel.

[0058] The above are merely embodiments of the present invention. Commonly known structures and characteristics are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, under the guidance of this application, improve and implement this solution in combination with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for positioning a central column, characterized in that: include: S1: Preparatory stacking tool; S1 includes: S1-1: Arrange the central column plates in order from the smallest to the largest level, and wipe and clean the upper clamp, lower clamp, and auxiliary clamp of the iron core. According to the preset drawing, place the channel steel on the stacking platform, and place the upper and lower clamps on the channel steel in parallel according to the preset clamp spacing size. At the same time, place the auxiliary clamp and iron plate on the upper and lower clamps at the same level, and place the insulating part on the upper and lower clamps. The insulating part includes an edge part and a middle part. The edge part is rectangular and placed on the upper and lower clamps. The middle part is strip-shaped and its two ends are placed on the edge part of the upper and lower clamps. S1-2: Place the smallest level central column piece in the middle part at one end of the upper clamping piece, and place the smallest level central column piece above the upper clamping piece through the central column positioning mold and make it fit the smallest level central column piece. S2: Place the central column positioning mold with the iron yoke on the iron core as the positioning reference. Adjust it to be symmetrical and uniform in the left and right and front and back. Start stacking the central columns. S3: Prepare four suitable electrical laminates, one each for the front and back of the upper and lower clamps and on both sides. Stack the silicon steel sheets for the iron core. Using the stacked central column as a reference, first insert the upper and lower iron yoke sheets, and use the corner hammer to flatten the pads until the entire iron core is stacked.

2. The method for positioning a central column according to claim 1, characterized in that: S2 includes: S2-1: Start stacking the center column pieces from the smallest level center column. When stacking, stack them in sequence from the smallest level center column to the largest level center column according to the stacking part inside the center column positioning mold. During the stacking process, the gaps of the center columns at each level are aligned. S2-2: Measure the edge distance of the center column at each level; S2-3: The stacked central column is pressed onto the top using a pad.

3. The method for positioning a central column according to claim 2, characterized in that: S3 includes: S3-1: Using the stacked central column as a reference, insert iron yoke plates and side column plates; the iron yoke plates are provided with V-shaped openings and bevels, the V-shaped openings match the sharp corners of the central column, and the bevels of the side column plates match the bevels of the iron yoke plates; S3-2: Use flattening pads to flatten the stacked yoke plates and side posts.

4. A central column positioning mold, characterized in that: It includes a positioning piece, which is V-shaped, and has multiple protrusions at the included angle of the V-shape, with gaps between the protrusions; The central column positioning mold is used in the central column positioning method according to claim 1.

5. A central column positioning mold according to claim 4, characterized in that: The positioning plate is made of silicon steel.

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