(1) Transformer foundation construction
Before the transformer is transported to the installation site, the construction of the transformer installation foundation should be completed. Transformer foundation piers are generally made of bricks. The strength and size of the foundation piers should be determined according to the quality and relevant dimensions of the transformer. Transformers with protective covers should also be equipped with metal supports. Both the transformer and the protective cover can be reliably grounded through the metal supports. The grounding wire is usually made of 40X4 galvanized flat steel and is welded to the nearby grounding grid by electric welding.
(2) Equipment inspection
Inspection of equipment points should be carried out by the installation unit, supplier unit and representatives of the construction unit, and records should be kept. According to the equipment list, construction drawings and equipment technical documents, check whether the specifications and models of the transformer body, accessories and spare parts meet the requirements of the design drawings, whether they are complete, and whether they are lost or damaged. The appearance of the transformer body was inspected for no damage or deformation, and the paint was intact and undamaged. Check whether the fuel tank is well sealed, whether there is any oil leakage, whether the oil level on the oil indicator is normal, whether there are any damage, defects and cracks on the insulating porcelain parts and epoxy resin castings. Problems discovered should be dealt with immediately.
(3) Secondary transportation of transformer
The secondary transportation of the transformer should require hoisting work and the cooperation of electricians. It is best to use a truck hoist or a chain hoist. When the distance is long, it is best to transport it by car. During transportation, it must be firmly fixed with steel wire ropes, and the driving must be kept stable to minimize vibration; when the distance is short and the road is good, winches and roller bars can be used for transportation. When lifting the transformer, the rigging must be inspected and qualified. The wire rope must be hung on the hook of the oil tank. The lifting ring on the upper plate is only used for lifting the core. This ring must not be used to lift the entire transformer. When transporting the transformer, care should be taken to protect the porcelain bottles. It is best to cover the high and low voltage porcelain bottles with wooden boxes or cartons to prevent them from being damaged. There should be no impact or severe vibration during the transportation of the transformer. When using mechanical traction, the traction point should be below the center of gravity of the transformer to prevent tilting. The transportation tilt angle should not exceed 15° to prevent deformation of the internal structure. When using a jack to lift a large transformer, the jack should be placed in a special part of the oil tank. Before transporting or disassembling large transformers, the directions of the high and low voltage sides should be checked to avoid difficulties in changing directions during installation.
(4) Transformer stable installation
When the transformer is in place, it can be thrown directly into the transformer room by a truck crane, or a temporary track can be set up with road wood, lifted to the temporary track with a three-step lift and a hanging chain, and then pulled into a suitable position indoors with a hanging chain. When the transformer is in place, attention should be paid to its orientation and distance from the wall, which should be consistent with the drawings. If not specified in the drawings, it should comply with the requirements of the design specifications. The track on the foundation of the transformer should be level, and the track gauge and wheel gauge should match. The transformer equipped with a gas relay should have a top cover with an upward slope of 1% to 1.5% in the direction of the gas flow of the gas relay. When the transformer is pushed on the wide side, the low voltage side should be outward; when the transformer is pushed on the narrow side, the oil pillow side should generally be outward. When a switch is installed, a width of more than 1200mm should be left in the operating direction. For transformers equipped with rollers, the rollers should be able to rotate flexibly. After the transformer is in place, the rollers should be fixed with a removable braking device. The installation of the transformer should take anti-seismic measures.
(5) Accessory installation
Transformers have many accessories, such as radiators, gas relays, moisture-proof respirators, thermometers, fans, high-voltage bushings and voltage switching devices, etc. The accessories should be installed according to the requirements of relevant specifications and product instructions.
(6) Transformer wiring
The primary and secondary connections, ground wires, and control wires of the transformer should comply with corresponding regulations. The construction of the primary and secondary leads of the transformer should not cause the casing of the transformer to directly bear stress. The working neutral line and neutral point grounding wire of the transformer should be laid separately, and the working neutral line should use insulated wires. In the grounding loop of the transformer neutral point, a detachable connection point should be made close to the transformer. The control wires of oil-immersed transformer accessories should be insulated wires with oil resistance. The wires close to the box wall should be protected by metal hoses and arranged neatly, and the junction box should be well sealed.
(7) Transformer handover test
The handover test of the transformer should be carried out by a laboratory licensed by the local power supply department. The test standards should comply with the "Handover Test Standard for Electrical Equipment Installation of Electrical Devices", local power supply department regulations and product technical data requirements
(8) Inspection of transformer before power transmission
Before the transformer is put into trial operation, it must be inspected by the quality supervision department before it can be put into operation. Inspections before the transformer is commissioned include:
① Various handover test documents are complete and the data meets the requirements.
② The transformer should be cleaned and wiped clean, with no residual debris on the top cover, no damage to the main body and accessories, and no oil leakage.
③The primary and secondary leads of the transformer have correct phases and good insulation
④Good grounding wire
⑤ The ventilation facilities have been installed and working normally, the accident oil drainage facilities are intact, and the fire-fighting facilities are complete.
⑥The throttle of the oil system of the oil-immersed transformer should be open, the throttle indication is correct, and the oil level is normal.
⑦Set the voltage switching device of the oil-immersed transformer to the normal voltage range
⑧The setting value of the protection device meets the specified requirements, and the operation and linkage test are normal.
⑨The transformer protection fence is installed, various signs are hung, and the door is locked.
Oil-immersed transformers, oil transformer manufacturers, oil transformer manufacturers, complete sets of equipment, high and low voltage switch cabinets, distribution cabinets, ready for shipment. New and old customers are welcome to call to purchase oil-immersed transformers. Transformer manufacturer's phone number Whatsapp/Wechat: +86 15824687445
