spic website: sep tianji power plant completes overhaul on unit 3 main transformer rapidly
the overhaul period of unit 3 main transformer was only eight days, and the related work included the replacement of gas relay of main transformer and high-voltage auxiliary transformer, replacement of oil flow relay, electrical test, and inspection of various parts of transformer, etc., with limited time and heavy tasks. due to continuous rainy weather in the early stage of the overhaul, the electrical test work was postponed again and again in order to ensure the validity of the test result. the testing personnel had to wait until the weather turned fine in the later stage of the overhaul, and then worked overtime to complete it.
in the overhaul work of unit 3 main transformer, the most time-consuming, complicated and difficult task was the replacement of the oil-level meter of the main transformer. two sets of preplans have been prepared for the construction technical scheme only, so that the better one could be selected according to the actual situation of the field equipment. in the process of oil-level meter replacement, the oil pouring operation is required for the oil conservator of the transformer. in order to ensure that the oil will not be contaminated and affect the operation of the transformer, the oil washing for the oil filter, spare oil tank and connecting oil tube had been carried out several times before the related work started. the overhaul personnel checked the tightness of various tubes and valves connections especially to ensure no oil leakage. during the oil filtering work, the chemical personnel were required to conduct sample inspection on the oil products, and finally sent the oil samples to anhui electric power research institute for inspection. the oil was not poured back to the oil conservator until the institute issued a qualified report.
the oil-level meter of unit 3 main transformer at tianji power plant was replaced smoothly, which solved the major safety hidden danger of abnormal display of oil-level meter, and thus provided strong support for unit 3 to operation under high load during the summer peak period.