Rewinding a Frame 400 Motor — Precision in Every Layer

Just completed the full rewinding of a Frame 400 electric motor, following a structured sequence of burn-off, insulation preparation, rewinding, and final impregnation. Motors of this size — with a shaft height of 400 mm — are typically used in high-load industrial environments, such as pumping stations, marine propulsion, or process systems requiring continuous, high-power duty cycles.

Process Overview

• Burn-off phase: All existing insulation and external paint was removed in our controlled burn-off oven, leaving surfaces impeccably clean and fully prepared for reassembly
• Rewinding: New coils were formed and inserted with precision, respecting slot geometry and thermal design constraints
• VPI treatment: A full Vacuum Pressure Impregnation cycle ensured complete resin penetration for maximum insulation life and thermal protection
• Final stage: Taping, slot wedges, varnish, and mechanical reassembly under standard IEC tolerances

From the Inside Out

The detail visible in the stator image reflects what we value in every repair:

• Material integrity
• Thermal resilience
• Mechanical alignment
• Long-term reliability

In high-power motors, rewinding isn’t just repair — it’s recovery of value, performance, and uptime.