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Transformer failure often occurs due to mechanical issues with its windings. Windings, arranged as cylindrical shells around the core limb, must endure dielectric stress, thermal demands, and mechanical forces, potentially leading to displacement. These forces, such as those from short circuits or lightning strikes, play a significant role. Understanding axial and radial forces is essential for analyzing the mechanical failure of transformer windings. These forces cause the windings to deform mechanically. Short circuits in windings can stem from various sources: mechanical faults during construction, insulation flaws, hot spot formation, copper sludge buildup, or low oil levels. Transient overvoltage may arise from lightning strikes, incorrect transformer connections, or short circuits in the low-tension system.

Mechanical Failure of Transformer Windings
Spiral tightening

•  Displacement of conductors/ radial spacers
•  Combined radial/ axial force cause spiraling/ tightening

End turn failure

• Combined force twist the end
•  Radial and axial force tilt the outside turn

Axial telescoping failure

•  Mechanical failure of clamping system
  •   Winding moves in opposite vertical direction
•  Axial instability
  •   Conductors slips/ get under one another

  Axial compression failure

•  Conductors gets tilted  due to opposing force

Axial expansion failure

•  Jacks/ bolts bend or shear
•  Opposing force break clamping plates

Radial tension failure

•  Coil collapses
•  Tears conductors insulation
•  Deformation causes axial instability

Radial compression failure

•   Conductor buckling

In summary, RCA is instrumental in understanding the mechanical failure of transformer windings, enabling organizations to address root causes, enhance maintenance practices, improve design and engineering, enhance safety and reliability, reduce costs, and foster continuous improvement in transformer operations.

Who should use the Mechanical Failure of Transformer Windings template?

• This fishbone template is typically used by engineers, technicians, or professionals working in the field of electrical engineering.

Why use this template?

• Using a Fishbone diagram for analyzing mechanical failures of transformer windings enhances problem-solving effectiveness, promotes collaboration, facilitates root cause identification, enables proactive risk mitigation, and fosters a culture of continuous improvement within organizations.
• Design your template or reuse this with some alterations for problem-solving in ProSolvr by smartQED.

Curated from community experience and public sources:

• https://www.ijert.org/research/transformer-failure-analysisreasons-and-methods-IJERTCOf
• https://www.ruggedmonitoring.com/blog-detailed/various-failure-modes-in-power-transformers#:~:text=Mechanical%20failures%20such%20as%20distortion,Electromagnetic%20Forces