Rectangular wires

Von Roll offers a complete range of enameled, yarn-covered or taped rectangular copper wires.

Your benefits

  • Different types of enamel with very good mechanical strength and bonding properties
  • Very consistent quality and dimension tolerances in line with industry standards
  • Wide range of dimensions, yarns and insulation builds available
  • Very thin grades for wind turbine generators
  • Improved mechanical strength, high-performance yarns and impregnation varnishes
  • Very high resistance to corona discharges for inverter applications
  • High-temperature class (original Pyre-ML® enamel used) with high- breakdown voltage
  • Soft wire for easy winding 
Flat wires covered

Von Roll produces a complete range of enameled rectangular copper wires according to IEC 60317-0-2 and NEMA dimension ranges, with Grade 1 or Grade 2, according to IEC or Quad, Heavy builds according to NEMA.

Duroflex® / FormvarEnameled wire with a coating featuring outstanding mechanical properties, mainly for windings in oil transformers and electrical counters.

Thermex® / HPAM / HDT-3000High-temperature wires with temperature indices up to 240°C. Chemistries are modified polyesterimide, polyamide-imide and aromatic polyimide (original Pyre-ML). The improved bonding resulting from nickel plating on the copper core significantly enhances their resilience when subjected to high temperature and radiation.

Thermibond®Self-bonding wires mean that motor or generator manufacturers do not need to use impregnation varnishes, thus reducing manufacturing time cycles. Two grades with different bonding strengths allow optimal fixation of the wires without damaging the enamel.

AustraShield®Corona discharge-resistant enameled wires for use in inverter driven motors. Lifetime under corona-discharge conditions for AustraShield® is 200 times higher than for standard enameled wires.


  • AC and DC motors and generators for classes 200 to 240
  • AC motors driven by inverters
  • Magnet and conductor coils subjected to voltage peaks
  • Motors and generators for the aviation and marine industry
  • Fire-resistant motors for tunnel ventilation
  • Motors and equipment in the nuclear field
  • Oil-filled  and dry-type transformers
Enameled flat wires

Von Roll offers a complete range of yarn- or fiber-covered rectangular copper wires in line with IEC 60317-0-2 and NEMA MW-1000 dimension ranges. All grades are available with a B-stage overcoat.

A bare or enameled wire braided with glass fibers and subsequently impregnated, suitable for a temperature range of 155°C to 240°C. A nickel plating on the copper improves the lifetime under high-temperature conditions.

Daglas® / Austraflex®
Bare or enameled wires braided with a mixed glass/polyester cover with a temperature range of 155°C to 180°C. Daglas® and Austraflex® have very strong mechanical properties allowing very high stresses and narrow bending radii during the bar-manufacturing or coil- forming processes.

VTV is a combination of Silix® and Daglas® wires. VTV is mechanically stronger than a Silix® wire, but has more glass content than a Daglas® wire.

VS 220 / VS 240 
Glass braided wires with high-temperature indices of 220°C and 240°C and excellent mechanical properties. VS 240 can directly replace a polyimide-taped flat wire used for traction motors. Mechanically, VS 240 is much stronger than polyimide-wrapped wires.


  • Roebel bars for power generators
  • Tooth coils
  • Traction motors up to 240 temperature class
  • Wind turbine generators
  • High-voltage rotating machines
  • Field  coils
Glass-yarn covered flat wires
Mica covered flat wires

Von Roll offers a complete range of bare or enameled, mica-covered rectangular copper wires according to IEC 60317-0-2 and NEMA MW-1000 dimension range, Grade 1 or Grade 2.

There are different types of Samicafilm® tape for use as wrapping around bare or enameled rectangular wires. For lower voltage rated machines subjected to high-voltage peaks an increase of insulation of only 0.2 mm is available. Further types are available for machines rated for up to 18kV and for temperature indices from 155°C up to 240°C.


  • Wind turbine generators
  • High-voltage motors and smaller generators
  • Mining motors

Polyimide-covered wires are bare wires taped with different grades of polyimide/FEP tapes. Depending on the application conditions, corona discharge-resistant or waterproof types are available. The polyimide yields high-temperature resilience, class 240 complemented by a high breakdown voltage. The corona discharge-resistant version provides a much higher resistance to voltage peaks than the standard polyimide. For applications in high-humidity atmospheres a waterproof polyimide variant can be used. To give a higher mechanical strength to the wire a glass covering will be applied. A nickel plating on the copper conductor results in outstanding behavior for high temperatures and in radiation fields.


  • Traction motors
  • Motors for heavy-duty applications (rolling mills, mining machines, oil pumps)
  • Aircraft generators and marine engines
  • Stirring coils
  • Motors for nuclear power plants

We also produce customized wires according to the application or customer specific requirements. By using special braiding or taping operations we are able to insulate different types of conductors like ETP or oxygen-free copper, nickel-plated copper, hollow conductors, superconductors and special alloys on request.