Transformer Repair and Rewinding
Repair, rewinding and overhaul of power and distribution transformers up to 132 kV and 20 MVA, with oil treatment and full diagnostic testing.
- Up to 132 kV
- Up to 20 MVA
- Power & distribution
- Since 1978Ranchi, Jharkhand
- 45+ yearsof experience
- 10,000+equipment repaired
- ISO 9001:2015certified
- 65,000 sq ftworks area
What we do
- Winding repair and complete rewinding of power and distribution transformers
- Coils wound on our transformer coil winding machines
- Transformer oil filtration
- Dissolved gas analysis (DGA) of transformer oil
- Oil dielectric constant and resistivity testing
- Complete diagnostic testing before dispatch
How the work is done
Typical steps for a transformer repair job at our works.
- 01
Diagnosis
Oil and electrical tests to locate the fault — DGA, ratio, tan delta.
- 02
Untanking & inspection
Core and windings are lifted out with our overhead cranes and inspected.
- 03
Rewinding
Damaged windings are rewound on our coil winding machines.
- 04
Drying
The active part is dried in our drying oven (40–200 °C).
- 05
Oil treatment
Oil is filtered on our 1200 LPH filter machine and tested.
- 06
Final testing
Ratio, tan delta & capacitance and high-voltage tests before dispatch.
Facilities used
Equipment at our 65,000 sq ft works in Ranchi used for this work.
| Equipment | Capacity / make |
|---|---|
| 2 × transformer coil winding machines | Centre height 1600 mm · bed length 2.5 m |
| Transformer oil filter machine | 1200 LPH |
| Drying oven | 40–200 °C · 3000 × 2500 × 1500 mm |
| Transformer winding ratio meter | Eltel TRM200 |
| Automatic tan delta & capacitance test kit | Subbal, 12 kV AC, 1 A |
| DGA test kit | Dhruva |
| High voltage test kit | RE, 100 kV AC / 70 kV DC |
Industries served: Power utilities, steel plants, coal mines, aluminium and railways — including NTPC, DVC, SAIL, CSPGCL, OPGC, GRIDCO and Jharkhand Bijli Vitran Nigam.
Questions about transformer repair
What transformer ratings can you repair?
Power and distribution transformers up to 132 kV and 20 MVA.
Do you test and treat transformer oil?
Yes. We carry out dissolved gas analysis (Dhruva DGA kit), oil dielectric constant and resistivity tests, and filter oil on a 1200 LPH oil filter machine.
Which tests are done after rewinding?
Winding ratio (Eltel TRM200), tan delta & capacitance (Subbal, 12 kV) and high-voltage tests (up to 100 kV AC / 70 kV DC).
Need transformer repair work?
Send us the equipment rating, make and the fault you see — we will get back to you with a plan and a quote.