Introduction to Caldweld

nVent ERICO Cadweld exothermically welded connections are engineered to provide a permanent, molecular bond that will not loosen or corrode. The connections are designed to maintain for the life of the conductor and/or installation. The nVent ERICO Cadweld connection has a current carrying capacity equal to or greater than that of the conductor and will withstand repeated fault currents without failing during operation. Once completed, installers can clearly ensure quality assurance by visual inspection of the new connection. With reliable connections that consistently exceeded IEEE® 837 2014 EMF test requirements as certified by an independent lab, nVent ERICO Cadweld is the ultimate welded connection.

The original nVent ERICO Cadweld exothermic welding system.

Invented in 1938. Patented in 1939. nVent ERICO Cadweld has been making connections easier for installers from the beginning and leading the industry in quality, performance and innovation ever since.

For contractors and engineers, we put everything you need to know about Cadweld in one place. How to specify, how to install, how to select a mold and stay up-to-date on all things Cadweld.

  • Product innovations
  • Tips and tricks
  • Specifications
  • Featured products
  • And more!

In 2020, nVent ERICO continues to innovate with an unwavering commitment to safe, adaptable, easy-to-use products. The nVent ERICO Cadweld Plus Impulse Exothermic Welding Control Unit incorporates new features designed to accommodate multiple power sources and improve safety.

Looking for the latest in cadweld?

The featured products page highlights new and innovative products in the cadweld product line

nVent ERICO Cadweld Plus Impulse Exothermic Welding Control Unit

nVent ERICO Cadweld Plus Impulse Exothermic Welding Control Unit brings you the highest level of flexibility and ease of use of any of our ignition systems.

Precision engineered, the Impulse ignition system lets you choose your power source: from off-the-shelf AA-batteries to the rechargeable Lithium-Ion packs you have on your job site.

New features focus on: safety, power and ease-of-use.


Make the Switch to our New Control Unit

Make ordering easy and get ready for the transition from our Cadweld Plus ‘blue box’ control unit to the NEW Cadweld Plus Impulse Exothermic Welding Control Unit


nVent ERICO Cadweld Plus One Shot

Our expanded range of durable disposable ceramic outer body eliminate the graphite mold and frame.

Cadweld Plus One Shot produces a permanent exothermic connection for either cable-to-cable or cable-to-ground rod configurations. The convenient single-use package makes the connection without a mold or starting material. cULus® listed and NEC® compliant, Cadweld Plus One Shots will not loosen or corrode over time.

nVent ERICO will prepare a project mock-up based on your design for your approval, and receiving an estimate is easy! Just provide project drawings and specifications to receive an all-inclusive proposal.

nVent ERICO Cadweld Plus for Rail

For over 80 years Cadweld has been the standard for making exothermically welded cable-to-rail connections on track. Continuing this legacy, nVent ERICO has introduced Cadweld Plus for Rail, featuring enhancements such as the Cadweld Plus Impulse ignition system and integrated weld material cups that make this integral product safer and easier to use.

Make the upgrade to Plus, contact the nVent ERICO rail product sales team!


Cadweld Catalog

Download our nVent ERICO Cadweld Welded Electrical Connections for quick reference of mold configurations, weld metal, tools, accessories and more.



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.


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

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.


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.

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

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

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


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

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


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

For more product information required please contact GLTM