Vacuum units for transformers is special equipment used to remove air from transformer tank. It also absorbs surface moisture and gas of transformer active part, improving its insulation performance. All 150-750 kV voltage transformers are subjected to vacuuming dehydration.
Prior to vacuum process – a tank should go through a leakage test: a vacuum not lower than 1000 hPa is created and maintained in the tank for one hour. After that a residual pressure is measured.
When the air has been evacuated and a transformer reached a perfect vacuum state acceptable for a particular transformer. The oil with vacuum is fed into a vacuum unit.
GlobeCore Vacuum Units for Transformers
GlobeCore developed BV vacuum unit for transformers that creates negative pressure in transformer tanks and drying electrical equipment. They are also successfully used in conjunction with degassing equipment.
GlobeCore vacuum units for transformers are two-stage vacuum systems consisting of vacuum and fore-vacuum pumps. The fore-vacuum pump is necessary for obtaining initial vacuum. The vacuum pump creates perfect vacuum. This combination allows to achieve a high performance of up to 2100 m3/h.