The specific operation steps of transformer oil thermal cycle are as follows:
1. The oil inlet pipeline of the oil filter is connected to the valve at the bottom of the transformer, and the oil outlet pipeline of the oil filter is connected to the oil filling valve at the top of the transformer body.
2. Starting with the vacuum pump oil filter, open the intake valve of the oil filter, open the transformer at the bottom of the valve, and then vacuum the oil filter of the oil injection pipe. The feed oil filter is used for self-circulating heating and oil temperature. Open the oil injection valve at the top of the transformer, so that the air in the oil injection pipeline is discharged through the vacuum pump, and open the oil injection valve of the oil filter for hot oil circulation heating.
3. When connecting the oil outlet pipeline of the oil filter, an exhaust plug is arranged on the oil filling valve at the top of the transformer body for discharging the gas in the pipeline. After filling the oil pipeline, open the valve at the top of the transformer body for hot oil circulation.
4. Before hot oil circulation under full oil condition, check whether the hygroscopicator is installed correctly and the breathing is smooth.
5. In the process of hot oil circulation, the oil temperature at the outlet of the filter should not be lower than 50 C, and the temperature in the tank should not be lower than 40 C. The oil after hot oil circulation should be sampled and inspected to meet the handover test standard.
6. After the completion of the hot oil cycle, it should be stationary for a period of time: 110 kV and below not less than 24 hours, 220, 330 kV not less than 48 hours, 500 kV not less than 72 hours.
7. After the transformer is stationary, exhaust gas is discharged several times from bushing, elevator, cooling device, gas relay and pressure release device, and the submersible electric pump is started until all the gas is discharged.
8. The exhaust in the tank must be carried out in accordance with the manufacturer's regulations.
The above steps take the capsule tank transformer as an example. Bellows type oil storage tank without respirator. Negotiate the operation steps of hot oil cycle and formulate special technical scheme.
In short, the thermal cycle of transformer oil should pay attention to temperature, valve, static, exhaust and oil quality.