CERB TRAFO is a proven leader in the transformer repair services in Bulgaria. Based on solid factors as experience and history, CERB TRAFO will be your reliable partner, guaranteeing quality, flexibility and professionalism in the following works and services:
  • Maintenance and repair on site or in the workshop of power, distribution
    and special transformers with voltage up to 400 kV
Works on site:
  • Revision and repair with opening of the active part, including repair of power switch ;
  • Revision and repair of on load tab changers and “soft” connections
    of bushings through existing openings ;
  • Drying the active part of the transformer ;
  • Replacement or repair of the cooling system, including change of the type of cooling (radiators, ventilators, valves, pumps, control cabinets – clamp boxes, wiring) ;
  • Revision or repair of the signal and protection equipment (lead-in insulators, relays, thermometers, level gauges) as well as racking fittings ;
  • Degassing, drying and filtering of transformer oil ;
  • Regeneration and passivation of transformer oil (types of
    processing against high acidity and sulphur presence) ;
  • Removal of transformer oil leaks from sealings and welding ;
  • Restoring the anti-corrosion protection (ACP) – sand blasting and
    applying anti-corrosion protection.
Workshop works:
  • Repair of the transformer core ;
  • Repair of transformer windings or replacement with new ;
  • Repair of the transformer metal constructions (tank, lid, bottom, expansion unit, pipeline) ;
  • Restoring the anti-corrosion protection of the transformer (cleaning, sand blasting, precoating and painting) ;
  • Replacement or repair of the transformer accessories (bushings, relays, thermometers, level gauges, faucets, valves, etc) ;
  • Replacement or repair of the cooling system of the transformer (radiators, coolers, ventilators, pumps, cabling, control cabinets) ;
  • Drying the active part of the transformer in a vacuum dryer units ;
  • Degassing, drying and filtering the transformer oil or replacement with new ;
  • Engineering for retrofit of transformers – calculations for new active parts and cooling systems ;
  • Technical projects for reconstruction – revision and repair of a transformer with opening the active part; degassing, drying and filtering of transformer oil or replacement with new; drying the active part of the transformer.
Manufacturing of Transformers:
  • Manufacturing of new power, oil transformer for voltage up to 110 kV ;
  • Manufacturing of new distribution oil transformers with power up to 1600 kVA and voltage up to 35 kV ;
  • Manufacturing of new special transformer as per client’s requirement (including locomotive, measuring transformers from 20 kV to 35 kV, earthing transformers) ;
  • Manufacturing of ohmic resistance up to 35 kV / 300 A, 10 seconds,
    own patent, in accordance with the standard IEEE 32 and the
    specific client requirements.