Frequently Asked Questions (FAQs)
General Copperweld Questions
Is Copperweld® widely used by utilities?
Yes, Copperweld Bimetallics invented Copper-Clad Steel over 100 years ago and the use of Copperweld® has been widely accepted by utilities across the world.

Does Copperweld® undergo corrosion?
The current manufacturing process provides an exceptional metallurgical bond that prevents separation and ingress of foreign molecules. There have been tests of Copper Clad Steel using our manufacturing process with cable buried in substations and being retrieved later for examination. In these cases, the copper was confirmed to meet ASTM standards. Where cut ends are left exposing steel to the environment, it has been shown that the rusting (oxidation) is non-linear and tends to use the oxidation process to create a “scabbing” or barrier to reduce rusting. Test reports are available for review and recommendations for preventing rusting of cut ends is available from your Copperweld Regional Manager.

Does Copperweld® undergo galvanic corrosion?
There are no known cases of galvanic corrosion with Copperweld wire and cable. As stated above, the Copperweld manufacturing process is so metallurgically sound that the copper and steel remain bonded with no interface disturbance over long periods of time(many decades) and conditions. The metallurgical bond is more robust than electroplating or hot dipping copper on steel, such as other materials used in the utility industry are manufactured. Applied voltage does not affect the CCS electrochemical cell because both metals are part of the same conductor and therefore at the same applied electrical potential.

Is Copperweld® approved by RUS?
Yes, Copperweld Bimetallics is the only manufacturer of Copper-Clad Steel that is approved by RUS.

Is Copperweld® readily available?
Copperweld Bimetallics is the only manufacturer of Copper-clad-steel in the United States and the only manufacturer of genuine Copperweld® in the world. Making this wire is all we do and we make sure we are responsive to our customers. Copperweld maintains a significant stock of all the most popular sizes and can ship quickly to anywhere in the world.

Are there other manufacturers of Copper-Clad-Steel?
Yes, there are other manufacturers who offer a copper-clad or electroplated steel product but they are all outside the USA or Canada. Raw materials are different, processes are different meaning the quality, performance, consistency and reliability can be vastly different. The only way to be sure you are buying the best-made product in the world is to insist on genuine Copperweld®.

Does Copperweld® comply with "Made in America" requirements?
Yes, Copperweld® is manufactured using only USA produced steel and is compliant with all Buy American requirements. American raw materials and American workers using American know-how for an American company producing the best product in the world. Anything other than genuine Copperweld® would be imported from foreign manufacturers.

Product Specification Questions
Is Copperweld® stiffer and more difficult to bend compared to solid copper?
To gain all the benefits that Copperweld® offers there may be some sacrifice in flexibility. The tradeoff between flexibility and the benefits Copperweld® offers is dependent on the size and construction. We use low carbon steel and then a full anneal (DSA or Dead Soft Annealed) to maximize flexibility and minimize stiffness. For example 4Thought™, our exact 4/0 size Copperweld® strand, is virtually the same flexibility as 19-strand 4/0 copper. Our 4 AWG single-end wire is a little less flexible than 4 AWG copper wire but not so much that it takes special tools to use it.

Why would I select Copperweld® for grounding rather than copper?
Copperweld® has more than double the fatigue strength of copper. Copperweld® has much higher tensile strength than solid copper. Copperweld® has excellent corrosion resistant properties. Copperweld® has ample current carrying capacity to carry a fault to ground. Copperweld® uses the same connectors as copper conductors. Copperweld® is actually lighter than copper so will yield more length per weight than solid copper.Copperweld® is theft resistant because the value of the copper is eliminated to a thief. Copperweld® is metallurgically bonded so the copper cannot be removed mechanically meaning the most it can be scrapped for is the price of steel. Copperweld® is also available disguised with our HIDE™ and CAMO™ options so it doesn’t look like copper. Copperweld® is much less volatile than copper from a pricing standpoint. Copperweld® can do all of this while offering significant cost savings during the initial installation plus cost savings over the life of the asset by eliminating the inordinate cost of replacing missing grounds.

Copperweld® Purchase Questions
How do I choose the correct size Copperweld®?
Every system is different so the sizing needs to be tailored to the specific application. The constant across any design is the maximum fault current the wire will be required to carry. Copperweld® should be sized based on the fault current it has to carry just the same as copper. However copper is physically weaker and often has to be upsized to gain physical strength and durability. Copperweld® is inherently strong so the primary consideration is the fault current level. Copperweld Bimetallics offers tools to make this easy to choose the correct size for any given fault level. We offer sizes ranging from 6 AWG (13.30mm2) pole grounds to 628.7 kcmil (318.55mm2) substation grounds covering just about any fault requirement you may have.

What packages are available?
Copperweld® wire and strand is available on a variety of packages. 25 lb. spools (green), coils (wrapped or unwrapped) up to 200 lbs net and wooden reels from 200 lbs. up to 4300 lbs. net are offered.

How do I buy Copperweld®?
Copperweld Bimetallics works with most all utility distributors in North America. We also have a network of Manufacturers Representatives covering the USA and Canada. Send us an email at and we will make sure we match you with the best channel for your requirements.

Resources and Data Sheets

Current Fusing Calculator
The recommended conductor size is: