Amorphous welding manufacturing is extremely important in the welding industry, and staff must pay more attention when conducting amorphous welding. Next, let's take a look at the precautions for amorphous welding manufacturing, as follows:
1. Amorphous coil
The coil of the amorphous transformer is a rectangular coil. Compared with the conventional circular coil, it is more difficult to wind and it is difficult to ensure the shape and size. Therefore, the winding process is emphasized here.
1. Low-voltage coil: Because the winding machine has its own tensioning device, the foil coil has a better winding effect. Generally, it can meet the drawing requirements after being shaped by hot pressing. Wire-wound coils are relatively difficult to wind, especially when multiple wires are wound in parallel, tensioning equipment must be used when winding. Before winding the coil, you must read the drawings, especially the skill requirements, to see if there are any special requirements, or if you don't understand, you can ask the technicians if you don't understand. When winding the first layer, pay attention to the paper skin of the paper-wrapped flat wire. When winding to the rectangular turn, the paper skin should be moistened (wipe the outer skin of the wire turn with a slightly damp rag), otherwise the insulating paper skin It is easy to crack and break, affecting the insulation strength, and even forming a short circuit between turns. If there is still cracking, it should be covered with insulation. When the coil is being wound, each turn should be tapped with a wooden hammer (be careful not to break the bottom insulation when the first layer is tapped, if necessary, use a 1.0 cardboard pad when tapping), so that the magnet wire And the winding die, between layers, close contact, especially at the rounded corners. The lap joint of the interlayer insulation and the wire should be placed in the direction of the short axis. The lap joint of each insulating paper itself should not be less than 20mm. For multi-layer coils, it should be noted that the position of the lap joint of each layer of insulation should be staggered by 10~15mm.
2. High-voltage coil: Because the high-voltage coil is directly wound on the low-voltage coil, the outer diameter of the low-voltage coil should be measured and recorded before winding. When placing braces outside the low-voltage coil, the four rounded braces can be slightly thinner, generally 2~3mm. The cardboard tube is surrounded by the braces. When the cardboard tube is surrounded, the corners of the cardboard should be moistened. The paper tube and the braces should be firmly attached and fastened with shortening tapes. During the initial winding, it is best to measure the outer dimensions of the cardboard tube to see if it meets the requirements of the drawing. Of course, after this process is skilled in the future, most of the coil windings can be omitted after they are qualified products. When the high-voltage coil is wound, braces must be placed at the four rounded corners, and the placement of the interlayer insulation and the lap joint of the wire is the same as that of the low-voltage coil.
3. When the high and low voltage coils are wound, they must be tightened and solidified, otherwise the outer diameter of the coils will be too large, and it will be difficult to achieve the size required by the drawings only by hot-pressing shaping. After the coil is wound, first measure the outer diameter, and if it reaches the error range required by the drawing process, then wrap the outermost layer of the coil with semi-dry glass adhesive tape or shortened tape.
2. Amorphous core
1. Lifting the iron core
(1) Hang the iron core according to the iron core number given by the quality inspection.
(2) Before placing the iron core, first acknowledge the difference between the stacking thickness of the iron core and the size of the drawing, and place cardboard of the corresponding thickness on the upper and lower clips to ensure that the interval between the iron core and the end face of the clip is the same as the interval given in the drawing. Similar, the error is 1mm (it can be roughly determined by the iron yoke spacer, and the cardboard plane of the iron yoke spacer is in contact with the horizontal plane of the iron window); The corresponding thickness of cardboard should be placed under the thinner iron core to ensure that the end faces of the iron windows of the four iron cores are in a straight line.
(3) When the iron core is placed on the clip, make sure that the vertical plane of the iron window is perpendicular to the horizontal plane of the clip, or use a small cardboard pad.
2. Open and close the iron core
(1) After each iron core is opened, it should be fixed with cardboard, and it is required to be closed within eight hours of opening, that is, the installation of the body should be completed within eight hours, otherwise the opened iron core will stand for a long time. It will be deformed by force to form no-load loss increase.
(2) Make sure that the phase sequence of the coil set on the iron core is correct, and then close the iron core.
(3) Before closing the iron core, adjust the coils of each phase so that the coil end faces are flat, and the end faces of the coils of each phase should be at the same level as possible. Use the iron yoke spacer to judge whether the height of the iron window is too large or too small after closing the iron yoke. If it is too large, reduce the thickness of the iron yoke pad, if it is too small, use the cardboard to ensure that the height error of the iron window does not exceed 2mm.
(4) The yoke can be closed after completing the previous work. Before closing, use cardboard or insulating paper to block the upper end of the coil to prevent the iron core chips from falling into the coil; when closing the amorphous iron chip, first place a 1.0 insulating cardboard underneath, and then press the first stack to place the coil. Put the iron core down, lightly press the non-chip chamfers on the left and right sides when putting it down, adjust the shape and size of the seam to ensure that the seam does not appear "eight" lines, the seam can be too large (no more than 5mm), and the end faces on both sides of the iron core Flat; every time you close two stacks, check whether the shape and size of the seam meet the requirements; after closing the iron core, stick it on the upper end face of the lap with masking tape, and put 1mm cardboard on it and then buckle it. Silicon steel sheet; after piercing the grounding sheet, brush KSD668 oil-resistant and high-temperature-resistant glass glue; use cardboard to flatten the iron core before fastening the clip to ensure that the end faces of the four iron cores are on the same level.
(5) The iron core must pay attention when opening and closing: the amorphous alloy iron core is very sensitive to mechanical stress, whether it is pulling, pressing, hammering or bending, it will increase the no-load loss of the transformer core. When the amorphous alloy core piece is closed, the lap order and lap orientation have a great influence on the no-load loss of the core. If the lap sequence is wrong, the lap dislocation and the open space are large, the no-load loss will increase by 20-200%. Therefore, it must be handled with care when operating, and try to prevent the iron core from being stressed.
3. Amorphous transformer body installation and general installation
The overall installation process of the amorphous transformer is as follows: hoist the appropriate iron core according to the capacity → open the iron core → set the coil → close the iron core → 180° gyrator body → put into the oil tank → oil filling.
1. Body installation
After the iron core is closed, use insulating cardboard to hold the iron core and the coil tightly. It should be noted that the short axis must be tightened, but the long axis should be slightly full, not too tight to prevent increased loss and noise. Then hoist the transformer body onto the flipper, and start flipping the body. When flipping, pay attention to the essentials of operation, and don't be quick.
2. Manufacture and wrapping of lead wires
(1) Before manufacturing the lead wire, look carefully at the drawing, and figure out the lead wire to be welded and its orientation; when wiring, the lead wire should be flat, straight, neat, and beautiful, and try to prevent the lead wire from interpenetrating. If it cannot be prevented, use it at the intersection Crepe paper plus 3mm thick insulation. After the lead wire is welded, it should be polished and deburred first, and then the insulation thickness should be wrapped according to the requirements of the drawing.
(2) After the A, B and C leads are welded and wrapped, they are directly drawn out. Pay attention to ensure the distance between the leads and the clips, coils and other leads. Do not make them into a "u" shape or "s" shape against the line On the circle or too close to other tap leads; note that A-Z, B-Y, C-Z connecting leads need to be wrapped with 3mm thick insulation in the position where other leads are inserted and touched;
(3) The leads and connecting pieces of the conductive rods of the high and low voltage connection sleeves should be circled or bent, leaving some margin to prevent the leads from being stretched and straightened.
3. General installation
(1) After the body is installed, blow the body with dry compressed air, and then send it to the drying room for heating and drying.
(2) After the body has been heated and dried, it should be checked whether the body is clean and whether there are conductive dust, grease, dirt or cloth tapes and other sundries. The upper and lower iron yoke pads and the winding pads should be aligned and pressed tightly without loosening. The outer surface of the coil should be kept clean, all the fasteners must be re-tightened, and the leads and insulating spacers are not allowed to loosen. Then use a 2500V megger to check whether the insulation between each coil and to the ground is good. The insulation resistance between the high voltage and low voltage coils to the iron core and the high voltage to the low voltage coil is not less than 200MΩ, preferably above 500MΩ.
(3) After the previous work is done, the body can be hoisted into the fuel tank. When the body is unloaded, the lead wires, wooden pieces and positioning threads should not be damaged. The body should be stably lifted, and all the hanging plates for lifting the body should be fully used. The body is connected with the tank cover structure, and the interval between the tank cover and the feet is adapted to the height of the fuel tank, and there is no hanging phenomenon after the body is unloaded.
(4) It is not allowed to exceed 12 hours when the body is exposed in the air from the time of release to the end of final assembly.
(5) The transformer oil injection shall be carried out according to the requirements of the process documents. When filling oil for the first time, first remove the pressure release valve on the upper end of the oil level gauge, fill the oil to a position about 20mm lower than the upper end of the oil level gauge, and then open all the high-pressure bushing bleed plugs, so that the air in the box is released from the high pressure The casing is discharged. When the casing is oiled, the oil injection is stopped and each casing is sealed.