Abstract:
Complex petroleum acids produced during service can attack the insulation and copper of the winding and metallic parts of the transformer. Corrosion of transformer is due to the presence of moisture, water should be removed by vacuum dehydration process. If acidity is in between 0.5 and 1.0 mg KOH/g the oil should be filtered and if its acidity exceeds from 1.0 mg KOH/g, the oil should be reconditioned. Reconditioning of the used oils takes place by (1) mixing the used transformer oil and soda lime in a settling tank and then filtering the transformer oil to remove the residue soda lime. (ii) Tri-sodium phosphate can also be used instead of soda lime. (iii) In Fuller`s Earth process, Fuller`s earth is used as an absorbent. It depends upon its large surface area for high absorption. Two fuller earth filters on the same unit are used for series filtration. After the purification of Fullers earth, vacuum dehydration in spray type chambers takes place and in this way reconditioning of the transformer oil will complete. (iv) In the activated alumina process, activated alumina is used as absorbent agent, which absorbs water and acid.
Page(s):
41-46
DOI:
DOI not available
Published:
Journal: Indus, Volume: 19, Issue: 10--11, Year: 1976