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Cadweld History

nVent ERICO Cadweld, the original exothermic welding system

We trace our roots back to 1903 — a time when very few homes or businesses even had electricity — with the founding of the Electric Railway Improvement Company (ERICO). The company in 1939 patented its Cadweld exothermically welded connection, an invention that paved the way for rail car companies to make repairs to rail tracks without large welding equipment. More than 100 million Cadweld connections are now installed in a broad array of applications around globe.


  • 1903

    The Electric Railway Improvement Company (ERICO) was formed to manufacture power bonds, signal bonds and related welding equipment.

  • 1938

    Dr. Charles A. Cadwell of the Electric Railway Improvement Company invents the Cadweld process – a copper-based, exothermic process for welding copper conductors to steel rails.



  • 1949

    Cadweld process is introduced for Cathodic Protection applications, specifically formulated to provide minimum heat effect on steel, which is especially important on thin-wall, high-stress pipes.

  • 1951

    Adapted the Cadweld process for use in grounding connections adapting the time savings from rail applications for streamlining commercial installations

  • 1959

    Cadweld One Shot developed – a disposable mold for one time use in connecting a copper conductor to conductor and conductor to a ground rod

  • 1988

    Cadweld Exolon introduced for low emission welding connections for sensitive indoor applications with electronic ignition and ceramic filters

Cadweld Signal Bonds
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  • 2003

    Cadweld Plus introduced as first exothermic welding system with self-contained welding material with electronic ignition

  • 2014

    Cadweld is first connection type to pass IEEE 837-2014 requirements for substation grounding – the most rigorous grounding connection qualification testing

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Cadweld Plus Control Unit
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  • 2020

    Next generation Cadweld Plus products, including the nVent ERICO Cadweld Plus Impulse Exothermic Welding Control Unit, improve on system safety and ease-of-use.

Erico Cadweld
Erico Cadweld

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