Determination of Acidity in Accelerated Aged Insulating Paper Impregnated with Different Insulating Oil

The presence of acidity in oil-impregnated paper insulation accelerate its degradation process. Currently, there are no international standards that regulate the assessment of inside insulation paper. At present, the paper condition is assumed to be represented by oil conditions. However, a recent experiment found that the partition coefficients of various acids produce very different concentrations of acid in the paper. This study will discuss the detail of the determination of the acid number of insulation paper. The samples of (Kraft) paper insulation impregnated with two different types of oils, i.e., uninhibited oil, and inhibited oil are used for the measurements. The paper samples treated in the same aging conditions; it was delivered with thermal stress at 130 °C in various aging times until 15 weeks. The investigation is carried out in 9 different methods. To distinguish one method to others, selection of measurement parameters such as the mass of the paper sample, the mass of pure water, paper sample processing, filtering process, the mass of extract and material to be titrated is done in a different way.