Tape Wound Cut Cores

Tape wound cut cores are ideal for transformer design engineers who require one to several thousand transformers in shapes that are unavailable in standard lamination sizes. They also are ideally suited where weight or dimensional requirements are critical and have to be reduced, including chokes, pulse applications and current transformers.

Magnetic Metals’ Tape Wound Cut Cores Offer:

  • The advantages of using Microsil™, including its excellent magnetic properties of grain oriented silicon iron in the rolling direction;
  • Lighter weight for same VA power rating;
  • The highest flux densities available – through 21.0 kilogauss – provided by our Supermendur™ material
  • Air gap that can be easily adjusted for specific choke design;
  • Outstanding pulse performance, including high pulse permeability with or without reset;
  • Operating frequency up to 40 kilohertz with thin gauge core material;
  • Operating temperatures up to 350 F;
  • Reduced core noise;
  • Easy selection and low assembly costs;
  • Wide range of core mandrels available from stock for quick delivery;
  • High quality assurance of your finished parts from our proven designs and advanced manufacturing facility;
  • Special sizes or shapes that can be readily manufactured to meet your custom or standard designs.

Available Shapes, Sizes and Materials

Magnetic Metals can produce almost any size single-phase or 3-phase tape wound transformer core without expensive tooling. Special geometric shapes and assembly configurations are available at minimal costs. Cores are manufactured with new computer-controlled precision equipment or with traditional tape wound cut core manufacturing procedures.

Materials include:

  • Amorophous alloys;
  • Cobalt iron;
  • Microsil™;
  • Nanocrystalline alloys;
  • Square 50 (Nickel iron);
  • Supermalloy™;
  • SuperPerm™ 80 (Nickel iron).

Visit our Advanced Grade Materials page for more information.

Core Construction

Magnetic Metals tape wound cut core manufacturing processes are designed to produce transformer cores having the lowest possible losses and magnetizing currents. Where required, special selection of steel is made to meet exacting specifications for very low loss, high pulse permeability, etc. Through improved cutting procedures and butt end preparation, the air gap at the face is kept to an absolute minimum. As a result, the assembled cores exhibit exceptionally low hum and low exciting current.

The finished product is final tested to both mechanical and electrical requirements as described in the EIA Standard for Cut Cores RS-217A and according to Magnetic Metals’ own stringent test requirements for cut cores.

Electrical Characteristics

Magnetic Metals cut core manufacturing processes are designed to produce transformer cores having the lowest possible losses and magnetizing currents. Where required, special selection of steel is made to meet exacting specifications for very low loss, high pulse permeability, etc. Through improved cutting procedures and butt end preparation, the air gap at the face is kept to an absolute minimum. As a result, the assembled cores exhibit exceptionally low hum and low exciting current.


Tape Wound Cut Core Design Manual Download Login or register to download the
Tape Wound Toroidal Core Design Manual 
for material performance data, core selection guide, and ordering information

Single phase cut core
Single phase cut core
3-Phase cut core
3-Phase cut core
Cut cores product examples
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