Assembled Transformer Magnetic Cores

An assembled magnetic core, or transformer core, is manufactured to the customer's design documentation. The supply can include cut core laminations, insulation components, core steelwork, stacking, assembly, testing and preparation for shipment.

Magnitosila has manufactured magnetic cores since 2015. The company has produced and supplied more than 4,000 magnetic cores for dry-type and oil-filled transformers, reactors and specialised equipment.

Types of magnetic cores

We manufacture standard and custom magnetic cores for dry-type and oil-filled power transformers, distribution transformers, reactors and specialised equipment. The design, number of limbs, lamination geometry and scope of supply are determined by the customer's documentation.

• assembled transformer magnetic cores and sets of individual components;
• three-limb and five-limb designs when specified in the drawings;
• cores for dry-type and oil-filled transformers;
• products using STEP-LAP, mitred, butt-lap or another agreed joint arrangement;
• custom solutions for reactors, chokes and specialised equipment.

Technical capabilities

Engineering capabilities

Before manufacture, we produce a complete 3D model of the magnetic core and agree the design decisions with the customer. This allows geometry, completeness and manufacturability to be checked before production starts.

We can design a magnetic core from completed design documentation, sketches or existing windings. Where required, we provide comprehensive transformer design taking into account the magnetic core, windings and specified performance parameters.

Quality control and no-load losses

Every item is inspected before shipment. We check geometry, completeness, assembly quality, marking and packing. For magnetic cores, we verify no-load losses and guarantee conformity with values agreed with the customer.

What production includes

• review of drawings, bills of materials and material requirements;
• development and approval of a 3D magnetic-core model before manufacture;
• longitudinal and cross-cutting of electrical steel;
• manufacture of core laminations, insulation parts and core steelwork;
• stacking, assembly and dimensional inspection;
• testing;
• packing and preparation for safe transport.

Supply format

The format of supply is agreed with the customer: a fully assembled magnetic core or a structure with temporary fixtures for safe transport can be supplied. This reduces the workload on the customer's assembly department and accounts for further assembly, insulation, packing and transport requirements.

Information required for a quotation

Please send an assembly drawing, lamination and steelwork specification, electrical-steel requirements and permissible losses. If some information is unavailable, we can perform engineering development from sketches, source data or existing windings.

Frequently asked questions

Can you manufacture a magnetic core to legacy drawings?

Yes. We work to the supplied design documentation, check the completeness of the input data and agree all points affecting manufacture and delivery before production begins.

Can a prototype be made before a production batch?

The possibility of a prototype and the subsequent production process are agreed for the specific project, batch size and required dates.

How are lead time and cost calculated?

The calculation depends on the design, electrical steel, scope of supply, mass, order volume and packing requirements. Drawings and a bill of materials help us prepare an accurate quotation.