It is often overlooked by us that whether sealed Transformer oil drums are stored in horizontal or in vertical positions. But, there is difference, especially when stored outside because of a phenomenon called ‘Breathing of Barrel’. Every sealed Transformer oil drum breathes in and breathes out due to variations in the ambient temperature conditions. Even though oil drum is completely sealed, during hot days the oil drum gets heated and the oil in the drum expands and pushes the air accumulated over the oil to its surroundings. When temperatures are cooled, the oil in the drum contracts and creates partial vacuum in the drum and sucks outside moisture mixed air into the drum. This breathing in and breathing out of oil drums happens even they are not opened once.
When oil barrels are stored vertically outside during rainy season, rain water settles on the top of the barrel with its bung submerged. During breathing in of the oil barrels, the water is sucked into the drum. Once, the water enters the drum, it gradually settles at the bottom and raises the oil level in the drum. As this process continues, more and more water settles at the bottom and deteriorates oil and sometimes deforms the shape of the drum also.
To avoid this, the following advices may be noted while storing transformer oil barrels.
- As far as possible Transformer oil drums should not be stored outside.
- Transformer oil barrel is to be stored in horizontal position so that; there is no accumulation of water on top of the drum during rainy season.
- Transformer oil barrel is to be stored in horizontal position with its bungs in 3 O’clock and 9 O’clock positions, so that positive pressure is maintained at bungs as the oil level in the drum will be above the bungs in this position. This prevents breathing of drum there by entering of moisture and dirt from surroundings into the drum can also be avoided.
- Oil drums are to be stored horizontally on good platform and covered.
- First in and First out method should be followed.
- As far as possible Transformer oil drums should be stored in clean, cool and dry places.