How does transformer oil reconditioning extend oil service life?

Reconditioning removes moisture, dissolved gases, and particulates via filtration, vacuum dehydration, and degassing. It can improve BDV, resistivity, and dielectric dissipation factor, slowing further insulation stress. However, it does not fully reverse chemical aging of paper insulation. If acidity and sludge precursors are high, full regeneration with adsorbents may be needed to restore oxidation stability and interfacial tension more effectively than simple filtration alone.