Repair of power transformers

Preventative maintenance of power transformers to be transformers of 80 MVA and more. All other output transformers for repair based on their technical condition, test results and other faults of power transformers. Scheduled preventive repair of the transformer: transformer opening, inspection and minor repairs of the active part and its individual devices, lifting fixtures, check the insulation of the core parts replacement, if necessary, gaskets, rubbing, cleaning. 

 

Types of repairs of power transformers 

• Current repairs - is performed on-site transformer is purely preventative maintenance. It performs maintenance personnel operating life of the installation. To carry out maintenance transformer is disconnected from the network. This type of repair is done without opening the tank and the excavation of the windings and other parts of the active part. At the current repair of power transformers possible partial discharge of oil

• Overhaul I - When overhaul type I (average), which is also called preventative, power transformer windings do not understand, therefore, for the customer operating the transformer under repair downtime will be small. This repair is carried out in a short time also because of the threat of dampening winding insulation that would require drying of the active part in the future. Atmospheric humidity begins to act on the active part immediately after its removal from the oil medium. If the repair is carried out on the windings, which, for whatever reasons, were removed from the oil, the drying will be inevitable. Therefore, special attention is paid to the conditions and rules of opening the winding and time finding them without oil.

• Overhaul II - Overhaul of power transformers, in addition to works carried out at an average repair, including repair of the active part with its dismantling and restoration or replacement of the main windings and insulation, and sometimes repair the magnetic system with pereizolirovkoy plates. Overhaul of the transformer caused in some cases, damage to the core, windings and insulation as a result of accidents, insulation deterioration. However, in the energy sector there is a relatively even-many domestic and foreign transformers obsolete designs that are subject to major repairs and reconstruction to improve their reliability and reduction of parameters in accordance with the new standards.