Tape wound toroidal cores

VDM Metals is the world's leading manufacturer of nickel-iron and iron-nickel alloy flat products. In the field of soft magnetic alloys, our portfolio includes classic strips and foils as well as high-quality toroidal tape strip cores based on DIN 42311. From melting the material to annealing and coating, all production steps take place under our own roof at VDM Metals.

Fields of application

Tape wound toroidal cores from VDM Metals are characterized by their unique material quality with a high degree of purity and optimum microstructure, as well as their dimensionally accurate production with tight tolerances. They are used for a wide range of applications. For example, they are used in summation current transformers for residual current circuit breakers as well as instrument transformers for protection and measurement purposes, furthermore in energy meters, ammeters, universal measuring devices, chokes and in control and regulation devices. Depending on the end application, toroidal tape cores from VDM Metals are available in various material grades, dimensions and with different finishes.

Product configuration



Inner diameter: min. 5 mm
Outer diameter: max. 745 mm, larger cores can be produced by rewinding
Strip widths: 5 to 55 mm, wider toroidal tape cores are assembled from partial cores
Strip thicknesses: 0.06 / 0.10 / 0.20 / 0.35 mm

Coatings / finishes of toroidal tape cores

The following coatings are available:

  • Unfixed
  • End faces lacquer-fixed (Fix-SV)
  • Impregnated with varnish
  • Powder coating (Fix-BK)
  • Dried, encapsulated in plastic troughs or other materials

Your advantages at a glance

The precision engineering division at VDM Metals offers:

  • production of small and large quantities
  • short delivery times 
  • all common dimensions
  • quality control and assurance through in-house production of the materials used
  • stock-keeping 
  • optimal technical equipment with three winding machines and four annealing furnaces as well as one longitudinal field annealing furnace
  • technical customer service at eye level
  • contract annealing for soft magnetic parts
  • coil coatings with mangesium methylate (hard coating) or magnesium oxide (soft coating) as well as thermal degreasing (outer diameter ≤ 720 mm; width ≤ 110 mm, inner diameter 300 or 400 mm with sleeve)

Do you have any questions? Please contact us.

Andreas Grüber
Andreas Grüber Senior Key Account Manager vCard
Route VDM Metals International GmbH Plettenberger Str. 2 58791 Werdohl
Zülfükil Tas
Zülfükil Tas Gruppenleiter Feinwerktechnik vCard
Route VDM Metals GmbH Plettenberger Straße 2 58791 Werdohl