Heat treatment is a controlled process in which the structure and properties of metal are modified through heating, holding, and cooling at defined rates.

Its purpose is to achieve specific mechanical characteristics — strength, hardness, wear resistance, ductility, or to relieve internal stresses.

At RER – Riga Electrical Machinery Factory, annealing, hardening, and shrink-fitting are performed with precision to ensure components withstand loads, wear, and long-term operation.

  • Copper parts are brought to 550–650°C and quenched in water to achieve the required ductility for coils and related components.
  • Parts exposed to high loads — bolts, dies, and punches — are hardened at around 1100°C and cooled in oil to reach the specified strength.
  • Retaining rings are heated to approximately 400°C and lowered onto the rotor, which is positioned vertically; as they cool, they contract, forming a precise interference fit that secures the assembly.

Controlled temperatures, precise timing, and consistent procedures ensure the long-term reliability of RER components.