Ensuring the sealing integrity of dry-type composite wall-through bushings is crucial for their durable lifespan. During installation and maintenance, the sealing structure should be carefully restored to its original state. Oil level control and adjustment: During operation, the oil level inside the bushing should be regularly observed. Adjustments are necessary if the level is too high or too low. When the oil level is too high, some oil can be released through the oil塞 on the flange; when the oil level is too low, transformer oil of the same brand as indicated on the nameplate, and that has passed quality treatment, should be added through the oil reservoir's filling port.

2. For products with normal oil performance in past preventive tests, the cycle of preventive testing can be appropriately extended to reduce the amount of oil extracted. If there are any doubts, please contact the manufacturer. This casing is strictly prohibited from being disassembled by yourself. Correct oil extraction steps: Clean the dirt at the flange oil plug, open the oil plug, slowly screw the oil nozzle into the center screw hole of the oil plug, press against the plug inside and tighten it, then press the sealing ring of the oil nozzle tightly; at this point, the transformer oil inside the casing will flow out along the inner hole of the oil extraction nozzle; after the oil is extracted, reverse the above steps to restore.

3. Caution: When unscrewing the oil nozzle, do not loosen the oil plug. If it is found loose, tighten it immediately using a 19mm socket wrench on the opposite side. The measuring terminal must be securely grounded. The measuring terminal is located at the flange of the sleeve for installing the bushing. When measuring the dielectric loss and partial discharge of the measuring sleeve, unscrew the terminal cover and insulate the terminal from the flange. After measurement, the terminal cover must be re-fastened to ensure reliable grounding. Absolutely no open circuit is allowed during operation.

4. The measured medium-loss value under 10kV may vary due to factors such as the measuring instrument, the product's location, and the measurement environment, which may not align with the factory test data. The transformer bushing is the main insulation device outside the transformer housing. The leads of the transformer winding must pass through the insulation bushing to insulate the leads from each other and from the transformer housing, while also serving to fix the leads in place. Insulation bushings come in various forms, including porcelain, oil-filled, and capacitor types, depending on the voltage level.

Ceramic tube sleeves are commonly used in transformers with 10kV and below, where a conductive copper rod is inserted within the ceramic sleeve, with air insulation inside. Oil-filled tube sleeves are often employed in 35kV transformers, involving oil filling within the ceramic sleeve and a conductive copper rod inserted inside, wrapped with insulating paper. Capacitive tube sleeves are utilized for high-voltage transformers above 100kV, comprising the main insulation capacitor core, outer insulation ceramic parts, connecting sleeve, oil pad, spring assembly, base, voltage equalizing ball, measuring terminals, wiring terminals, rubber washers, and insulating oil.