This article describes the disassembly and repair of oil-immersed self-cooled, oil-immersed air-cooled, and forced oil-circulation air-cooled transformers, as well as the maintenance of dry-type transformers. Figure 1 shows the oil-immersed self-cooled and oil-immersed air-cooled transformers. Transformer structure.
1- Thermometer: 2- Famous brand: 3- Moisture absorber: 4- Oil level gauge: 5- Explosion-proof tube: 6-Oil conservator (oil pillow); 7- Gas relay: 8- High-pressure casing: 9- Low-pressure casing ; 10- Tap switch: 11- Fuel tank: 12- Iron core: 13- Winding: 14- Drain valve: 15- Trolley: 16- Door 17- Times thermometer; 18- Oil purifier: 19- Breathing apparatus : 20- radiator, 21- grounding bolt; 22- oil sample valve
Preparation work for transformer overhaul
- Personnel Organization
The preparation of personnel, tools and consumables, the specific number of personnel should be determined according to the actual situation - Conduct a comprehensive survey of the main transformer
Conduct a comprehensive survey of the main transformer:
① Reasons for overhaul
②Last overhaul report and remaining issues
③Recent maintenance report, test report, oil chemical test report
④Main transformer 3 years operation record
⑤Operation record of on-load tap-changer and no-load tap-changer maintenance test report
⑥Model parameters of main transformer, on-load external switch and main accessories, shape and size of main key components
⑦Whether there is a renovation project, if so, a renovation plan should be made
⑧Understand all existing defects
⑨ Formulate “three measures” (safety, technical and quality measures) and construction plan - Technical data preparation
①Transformer factory data and maintenance technical data
②High-voltage casing maintenance technology and standards
③Overhaul technology and standards for on-load external switches and off-excitation tap changers
④Cooler, radiator, maintenance technology and standard
⑤ Oil pump and fan maintenance technology and standards
⑥Oil flow relay, gas relay, pressure relief device, maintenance technology and standard
⑦Overhaul process standard for oil conservator and magnetic oil level gauge
⑧Oil purifier maintenance process standard
⑨Temperature controller maintenance process standard
⑩General maintenance process standard for small components of power transformers, including oil drain, butterfly valve, moisture absorber, oil mark, and grounding wire - Preparation of common safety equipment
①CO2 fire extinguisher
②Work clothes (dedicated)
③Ground wire
④Insulating shoes and gloves
⑤Oil resistant work shoes
⑥ Goggles
⑦Safety belt - Preparation of common tools and equipment for transformer maintenance
①Insulation resistance
②AC voltmeter
③Clamp-type ammeter
④Multimeter
⑤Vacuum gauge
⑥Hygrometer
⑦Thermometer
⑧Electric bridge
⑨Vernier caliper
⑩ feeler gauge
⑪Wire rope
⑫Pulley
⑬Light aluminum alloy ladder
⑭Rubber power cord
⑮Temporary power switch
⑯ Oil filter paper hole punch
⑰Various adjustable wrenches
⑱ Roller bars for lifting and carrying
⑲A variety of screwdrivers
⑳Jack - Preparation of main consumable materials
①Cotton yarn
②Flour (as required)
③White cloth tape
④ Hacksaw blade
⑤ Sponge
⑥ Wire
⑦Sandpaper
⑧Plastic belt
⑨Cleaning agent
⑩Sealing strip
⑪Alcohol
⑫Insulation tape
⑬ Welding rod
⑭Plastic cloth
⑮ oil filter paper
⑯Silk cloth
⑰Towel
⑱ Washing powder
⑲602 glue
⑳Various gaskets and replacement parts
