Traction Transformers
Meeting the complex demands
of railway applications
Transformers used in the railway industry face unique operational challenges. Additional complexities often related to space and weight constraints, fluctuating loads, mechanical stresses, and stringent energy efficiency requirements demand specialized insulation systems capable of maintaining long-term performance under dynamic conditions.
Working closely with the world’s largest transportation suppliers, Weidmann’s specialists deliver high-performance transformer insulation solutions tailored for traction transformer applications. Our materials are engineered to support maximum reliability, thermal management, and mechanical stability—ensuring mass transportation achieves peak efficiency and fault-free operation while meeting strict railway regulations.
As freight and passenger rail usage increases and the industry continues to shift from diesel to more sustainable options, the demand for high-efficiency onboard transformers continues to rise. Weidmann is committed to advancing rail electrification by collaborating with our customers to provide tailor-made insulation solutions that support innovation, enhance transformer performance, and power the future of sustainable transportation.
Cylinders
Cylinders are used as support for windings and can be produced either in Transformerboard T4, in composites materials like EPGC22 or PFCP, or Nomex® 993 PSB depending on the mechanical, electrical, and thermal class required.
Cylinders can also serve to divide oil gaps into several smaller oil gaps using the so-called ‘barrier technique’. In this way, substantially increased diametric strength is achieved at given clearances.
End Rings / Clamping Rings
End Rings/Clamping Rings support the transformer windings and are designed specifically to the rigidity and maximum force requirements of the transformer.
Manufactured in Transformerboard T4, PFCP, EPGC 22, or Nomex® 993 PSB, they must be able to withstand bias and short-circuit forces in order to protect the winding.
Cooling Ducts
Cooling Ducts, designed to help increase the capacity of the transformer to carry load without reaching critical hot spot temperature, are available in different classes – Cellulose 105°C, Nomex® 220°C and Hybrid 180°C.
Cooling ducts are made from supporting paper with either glued or ultrasonic welded strips in different materials providing the necessary cooling channels for thermal stability. Gluing can be applied to Hybrid and Cellulose, and welding is only suitable for Cellulose.
Milled Parts
Weidmann offers a range of parts in different materials, which are machined or cut to size according to our customers’ requirements and drawings. Parts can be in Transformerboard T4, Nomex® 994 PSB, composites, and KP wood as C1R, C2R, or C4R.
Board
With excellent dielectric properties, high compressive strength, and proven resistance to thermal and mechanical stresses, Transformerboard is ideally suited for the rigorous operating conditions of traction transformers.
Coated Paper
Engineered for demanding traction transformer applications, DPE Paper delivers exceptional dielectric strength, high mechanical flexibility, and precise conductor insulation to support reliable performance.
Nomex Toothband
Designed to avoid the occurrence of overheating, toothband consists of a single layer of Nomex insulating paper carrier tape on which blocks of Nomex 994 Board are welded.
Weidmann On-Board Transformer Insulation Solutions
Products are capable of withstanding different thermal classes for cost-optimization of On-Board Transformers, with a high level of reliability and safety
Leading supplier or NomexR high temperature thermal insulating technology for traction transformers in collaboration with DuPont
Extensive knowledge of Transformer insulation system deign and specification
Supplying On-Board Traction Transformer insulation solutions for over 30 years
Multiple global locations and established partnerships providing a worldwide service
Products available in ‘kit form’ for efficient & cost-effective purchasing and distribution
Established Research & Development program
‘One-Stop Shop’ for On-Board Traction Transformer insulation products & accessories
Wide product portfolio, manufactured to international standards & developed to provide a complete solution for traction transformers
All materials are tested in our Central Laboratory and are suitable for On-Board Transformers immersed in oil mineral and ester
Why choose Weidmann?
First-class insulation for traction transformers
Weidmann On-Board Transformer Insulation Solutions
Full support with Weidmann Knowledge Services
