1, check the butterfly valve shaft, baffle and other components are complete, flexible and tight, replace the gasket. The 0.05Mpa hydraulic test, the baffle should be closed tight, no serious leakage, shaft seal well, "open", "closed" position marked clear and correct. 2, the throttle (the accident row of the throttle, put the throttle) should be disassembled maintenance, grinding and replacement of seal packing, maintenance should be done 0.15Mpa hydraulic test should not have leakage. 3, on the transformer body and accessories minis vent, drain plugs, oil-like throttle and other travel a comprehensive inspection, replacement of gaskets should be sealed without leakage. Second, talk about transformer oil treatment methods: In order to improve the transformer oil dielectric strength, dielectric loss factor and other indicators, the transformer oil in the fuel tank before injection, must be processed to remove the oil moisture, gases and impurities. In practice, we deal with the different types of transformer oil targeted, the effect is better. 1, For ordinary transformer oil contaminated by impurities such as water and dust, you can use plate and frame pressure filter, after many cycles of filtration, usually to meet the requirements. Its principle is to use filter paper to absorb moisture and filter impurities. Because of its simple structure, easy handling, but also widely used. The disadvantage is that the filtration is not complete, the removal of fine impurities is not good, but the cost is relatively high, when the water is large, the filter paper to be replaced frequently. 2, now commonly used is a vacuum oil purifier, which not only completely remove the oil and gas, but also effectively remove minor impurities. The process is: to be dealt with transformer oil → rough filter → fine filtration → vacuum dehydration degassing → heating oil clean oil. Coarse filtration uses a metal mesh and a strong magnet. Fine filtration usually filters small impurities of 1 μm to 1 μm. At present, many types of fine filters, sintered metal powder materials, metal microporous materials, ceramic filters and the use of special filter paper filter core and so on. Transformer oil heating vacuum degassing deaeration. The principle is to vacuum the tank, the heating transformer oil spray method to form a mist, leaving the oil gas and water escaping. Oil temperature is generally around 65 ℃, not too high, so as to avoid oil aging. Dehydration degassing this method is better, is currently the more commonly used method. However, if the oil is sprayed into a very fine mist, it is easily pumped by the vacuum pump. If the oil is sprayed into oil beads with a certain diameter, the oil beads have a high interfacial tension, so that the moisture and the gas in the oil beads are not fully exerted. To this end, the diameter of spray Shantou should choose the appropriate, and generally need to set several baffles at the pump exhaust port to prevent the transformer oil is pumped by the vacuum pump. At present, foreign and domestic also use a more advanced membrane dehydration degassing method is to make the oil into the tank, after some degassing components to form a very thin oil film, and the film has been to complete the dehydration degassing the entire process , So that the oil in the water and gas easily removed. 3, the treatment of contaminated transformer oil. Polluted transformer oil (commonly known as dirty oil) refers to the colloidal contaminated transformer oil formed by the combination of minute impurities and oil molecules, and transformer oil, which has been used for many years, and is generally released for rework products Oil (the pH of this oil is already low). This type of dirty oil must be treated with adsorption to improve the oil index. Ordinary use of silica gel (SiO2) or activated alumina (A12O3) as adsorbent. Sludge treatment system, in order to ensure full contact with the silicone oil and transformer oil, and easy to replace the silicone in the silicone tank set aside a number of partitions, the silica gel into the small bag rotating, can not be loose. After heating the transformer oil into the silica gel tank, make a certain period of time to make it give full play to the adsorption effect, and then injected into the net oil tanker. In the treatment process should be regularly monitored to determine the adsorption effect, when the adsorption effect is not obvious, it should consider replacing the silica gel. Ordinary silicone dosage by weight of oil accounts for about 3% to 5%. Sludge treatment system should be separated from the new oil treatment system to avoid cross-contamination. Oil tanks, containers, etc. that have been used for the disposal of dirty oil must be thoroughly cleaned before they can be reused for normal production of oil systems.