| 摘要 |
PURPOSE:To enable to weld the outside part of a transformer without having deterioration in quality of the insulator and the like contained therein by a method wherein a connecting pipe is provided on the upper part of a transformer tank, and an airtight member having low moisture permeability is deflated and installed in a tightly fixed manner. CONSTITUTION:Insulating oil is filled as high as the upper part of the section to be welded, for example, up to the upper part of a conservator 7, a connecting pipe 9 having a suitable inside cubic volume is provided, and insulating oil is filled up to the position indicated by the oil level 10 of the connecting pipe 9. Then, the upper aperture of the connecting pipe 9 is covered by a freely deformable dust cover 11 of low moisture permeability having the amount of variation of inside cubic volume larger than the amount of variation of cubic volume of insulating oil, and the space between the connecting pipe 9 and the cover 11 is airtightly sealed. Then, a prescribed welding work is performed. While said welding work is being performed, the variation in cubic volume of the filled up insulating oil is generated as shown by the oil level 10a. Also, the pressure in the tank is removed by the inflation of the cover 11 for the temperature rise of the insulating oil in addition to the variation in cubic volume of the insulating oil. As a result, the reconstruction by welding and the like can be performed in the state wherein the tank is installed. |
