HVDC Transformer Repair: A Case Study

5th December 2024

At an electricity substation in Mexico, an HVDC transformer repair was urgently needed to address persistent oil leakage and water ingress through pipework connections and fittings. These issues risked compromising transformer performance, safety, and longevity. To prevent further deterioration, a durable and reliable sealing solution was essential to maintain operational integrity and protect the transformers from harsh environmental conditions.

Resimac’s HVDC Transformer Repair Solution

Surface prepared to ensure optimal adhesion.
Sealed and protected with 104 Metal Repair Fluid XF, reinforced with 808 tape.

Application Details

The steel substrate was abrasive blasted to SA2.5 with a 75-micron profile, following ISO 8501/4 SA2.5 (SSPC SP10/NACE 2) standards, to ensure proper surface preparation and optimal adhesion. Bolt heads, flange joints, and other mating surfaces were precisely stripe coated with 104 Metal Repair Fluid XF, applied using a brush and plastic applicator to create a uniform base layer.

To reinforce the repair, a layer of 808 Reinforcement Tape was embedded within the coating at flange joints and critical areas, enhancing mechanical strength and long term durability. This combination ensured the repaired sections could withstand operational stresses and resist environmental challenges. Finally, all treated areas were overcoated with an additional layer of 104 XF, fully encapsulating the repair and providing robust sealing against oil leakage and water ingress.

Products Used

104 Metal Repair Fluid XF
808 Reinforcement Tape

Results and Benefits

The multi-layered application of 104 Metal Repair Fluid XF created a durable seal for the HVDC transformer components, effectively preventing oil leakage and water ingress. The integration of 808 Reinforcement Tape added strength and ensured the repair could withstand the challenging HVDC environment. This reliable solution reduced the risk of future leaks, minimised maintenance requirements, and ensured consistent transformer operation. By maintaining operational reliability, the repair supported continuous power delivery, enhancing both safety and efficiency at the facility.